Abstract Book

14th Annual PhD Day

March 20, 2019

PhD Day 2018 at the GFZ

Programme

Morning Sessions

08:00–08:45 Registration

08:45–09:30 Introduction/Informational talksIntroduction by Dr. Schwartze

Talk by Dr. Hüttges

Talk by Prof. Dr. Merz and Prof. Dr. Weber (Liaison Lecturers)

Talk by GeoDocs

Talk by HelmholtzJuniors

Election of new GeoDocs and HelmholtzJuniors

09:30–11:00 EGU talks I & PICO Presentations

09:30 Nasim Karamzadeh: „Source array configuration and applications in crustal structure studies“

09:45 Jianli Ma: „Potentials for Power-to-Gas based subsurface energy storage in China“

10:00 Alexandra Mauerberger: „Scandinavian Lithosphere Structure derived from Ambient Noiseand Surface Waves“

10:15 Johanna Menges: „High sediment export from a trans-Himalayan semi-desert driven bylate Holocene climate change and human impact“

10:30 Jannes Münchmeyer: „Improving magnitude scale consistency through boosting treeregression and 3D source correction“

10:50 [PICO] Joana MacLean: „Microbiology of the terrestrial ‘plastisphere’ - enrichmentand characterization of plastic-associated microbial communities“

10:52 [PICO] Leonie Pick: „Magnetic Field Characteristics Observed on the Ground ReliablyClassify Historical Geomagnetic Storm Drivers“

Coffee

11:00–12:00 Postersession I (odd Poster Numbers)

12:00–13:00 FameLab

Lunch

Afternoon Sessions

13:45–14:00 Announcement of the FameLab winners

14:00–14:35 EGU talks II

14:00 Cameron Spooner: „Mass distribution across the Alpine lithosphere -Results from a gravity constrained model of the Alps and their forelands“

14:15 Irina Zhelavskaya: „A combined neural network- and physics-based approachfor modeling the plasmasphere dynamics during extreme geomagnetic events“

14:35–14:45 Group photo

14:45–14:50 Admission to the lecture hall (seats have to be taken by 14:50)

15:00–15:30 Talks by MinistersGreetings by Prof. Hüttl

Talk by Anja Karliczek (Federal Minister for Education and Research)

Talk by Martina Münch (Minister for Science, Research and Culture (Brandenburg))

15:30–16:15 Talks by Institute Directors

Talk by Prof. Dr. Dr. h.c. Reinhard Hüttl (Scientific Executive Director of GFZ)

Talk by Prof. Dr. Ottmar Edenhofer (Director of PIK)

Talk by apl. Prof. Dr. Bernhard Diekmann (Head of AWI Research Unit Potsdam)

16:15–16:23 FameLab finalists presenting their talk

16:23–16:30 FameLab Awards Ceremony

Coffee

16:30–17:30 Postersession II (even Poster Numbers)

17:30–18:00 Invited talk by Martin Otto - Transfer/Innovation

18:00–18:15 PhD Day Awards ceremony and closing remarks

Get together

from 18:15 Music, food, non-alcoholic drinks and beer

Page No. ii

Contents

A0 posters: Poster Session 1: 11:00 – 12:00 (odd Poster Numbers)Poster Session 2: 16:30 – 17:30 (even Poster Numbers)

xi

Nada Abdel-Hak – 3.6 - Chemistry and Physics of Earth Materials . . . . . . . .Experimental studies on NH+4 -phengite: Spectroscopic insights on NH

+4 incor-

poration and NH+4 distribution phengite-fluid at high P and T conditions . . . 1

Karsten Adler – 3.2 - Organic Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Present and past microbial signatures in deep sediments of the Hartoušov CO2mofette system, NW Bohemia . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Amandine Amemoutou – 4.2 - Geomechanics and Scientific Drilling . . . . . . .Moment tensors of waste-water disposal induced seismicity in Southern Kansas 3

Nikita Aseev – 2.8 - Magnetospheric Physics . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Reanalysis of ring current electron phase space densities using Van Allen Probeobservations, convection model, and Kalman filter . . . . . . . . . . . . . . . 4

Stephan Bentz – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . . . .Analysis of microseismicity framing MW > 2.5 earthquakes at The Geysersgeothermal field, California . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Aglaja Blanke – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . . . . .Sensitivity and stability analysis of coda quality factors at The Geysers geo-thermal field, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Fabio Brill – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Can flood intensity be approximated from current satellite-based water masks? 7

Chaojie Cheng – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Evolution of stressed fractures associated with fluid-rock interactions . . . . . 8

José Cruces-Zabala – 2.7 - Near-Surface Geophysics . . . . . . . . . . . . . . . . . . . . . .2D Magnetotelluric imaging of Northwest Venezuela. . . . . . . . . . . . . . 9

Kai Deng – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . .Deposition and retention of meteoric 10Be in river terraces of an active moun-tain belt during the Holocene . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Maximilian Döhmann – 2.5 - Geodynamical Modelling . . . . . . . . . . . . . . . . . . . .Asymmetric Rift Evolution: Geodynamic Modeling of the East African RiftSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Márton Pál Farkas – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Numerical investigation of hydraulic stimulation and related induced seismicityin Pohang fractured geothermal reservoir, South Korea . . . . . . . . . . . . 12

Nils-Peter Finger – 1.3 - Earth System Modelling . . . . . . . . . . . . . . . . . . . . . . . .An integrated 3D model of the South American upper mantle . . . . . . . . . 13

Hector Gonzalez – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Estimation of Energy reserve at Los Humeros geothermal power plant . . . . 14

Yufu Han – 3.2 - Organic Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NSO Compounds in Oil-Bearing Fluid Inclusions - Development of A Clean-upMethod Suitable for FT-ICR-MS Analysis . . . . . . . . . . . . . . . . . . . . 15

Theresa Hennig – 3.4 - Fluid Systems Modelling . . . . . . . . . . . . . . . . . . . . . . . . .Uncertainties of diffusion models in Opalinus Clay . . . . . . . . . . . . . . . 16

Johannes Hierold – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Experimental investigations on the hydrogen solubility in high saline fluidsunder reservoir conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Anna Jentsch – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Systematic soil gas studies for volcano-tectonic analyses of the Los HumerosGeothermal Field, Mexico. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Julia Kalanke – 4.3 - Climate Dynamics and Landscape Evolution . . . . . . . . .A high resolution (varved) Holocene record from Arid Central Asia and itspaleo-environmental implications . . . . . . . . . . . . . . . . . . . . . . . . 19

René Kapannusch – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . . . . . .Glacial influence on late Pleistocene paleo-erosion rates in the north-westernHimalaya, India . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Kathrin Kirchen – 1.3 - Earth System Modelling . . . . . . . . . . . . . . . . . . . . . . . . .Ocean signals in Earth’s magnetic field (OceanMag-II) - first insights . . . . . 21

Friederike Klos – 1.4 - Remote Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Hyperspectral Lithium-Pegmatite Detection – A Case Study Norway, Hoydalen 22

Nicole Köllner – 1.4 - Remote Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Imaging Spectroscopy for Mineral Exploration - Case Studies . . . . . . . . . 23

Friederike Koerting – 1.4 - Remote Sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Proximal Hyperspectral Outcrop Scanning - A Geological Use Case Study . . 24

Milena Latinovic – 1.3 - Earth System Modelling . . . . . . . . . . . . . . . . . . . . . . . . .Validation of 1D GIA models in Baltic Sea with sea-level index points . . . . . 25

Maria Leonhardt – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . .Source Characteristics of Induced Seismicity associated with the Stimulationof an Enhanced Geothermal System in Finland . . . . . . . . . . . . . . . . . 26

Zhen Li – 3.4 - Fluid Systems Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Quantification of coupled thermo-hydro-chemical processes in the LArge scaleReservoir gas hydrate Simulator by numerical modelling . . . . . . . . . . . . 27

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Christin Lindemann – 4.3 - Climate Dynamics and Landscape Evolution . . .Differences in sedimentation response to Younger Dryas climate change in athree lake cascade in northern Poland . . . . . . . . . . . . . . . . . . . . . . 28

Igor Lisac – 4.7 - Earth Surface Process Modelling . . . . . . . . . . . . . . . . . . . . . . .Application of a model for point-wise prediction of streamflow statistics usingclimatic and geomorphologic data . . . . . . . . . . . . . . . . . . . . . . . . 29

Jiabo Liu – 4.3 - Climate Dynamics and Landscape Evolution . . . . . . . . . . . . .Magnetic mineral diagenesis in the Black Sea - from lacustrine to marine . . . 30

René Mania – 2.1 - Physics of Earthquakes and Volcanoes . . . . . . . . . . . . . . . .Dome growth during the 2016-2017 eruption sequence at Bezymianny volcano,Kamchatka, measured by high-resolution TerraSAR-X and photogrammetricdata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Evgeniia Martuganova – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Vertical Seismic Profiling using Distributed Acoustic Sensing technology atthe Groß Schönebeck geothermal research site, NE German Basin . . . . . . . 32

Ayse Duha Metin – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .What is the effect of spatial dependency in regional flood risk estimation? . . 33

Lisa-Marie Moskwa – 3.7 - Geomicrobiology . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Effects of repeated wet-dry events on microbial community dynamics in Chi-lean soil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Chinh Nguyen Thai – 1.1 - Space Geodetic Techniques . . . . . . . . . . . . . . . . . . .Global distribution of Equatorial Ionization Anomaly (EIA) crests during solarcycle 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Peter Niemz – 2.6 - Seismic Hazard and Risk Dynamics . . . . . . . . . . . . . . . . . .Acoustic emissions induced by a hydraulic-fracturing experiment at the ÄspöHard Rock Lab: Continuous vs. progressive injection scheme . . . . . . . . . 36

Sulung Nomosatryo – 3.7 - Geomicrobiology . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Geochemical Characteristics of Lake Sentani, Papua Province, Indonesia . . . 37

Ralf A. Oeser – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . . . . . . . . . .Radiogenic and stable Strontium isotopic fingerprints of ecosystem nutrition . 38

Lea Pennacchioni – 3.6 - Chemistry and Physics of Earth Materials . . . . . . .Elasticity and stucture evolution of carbonates at upper mantle conditions . . 39

Gesa Petersen – 2.1 - Physics of Earthquakes and Volcanoes . . . . . . . . . . . . . .Automatized quality control and moment tensor inversion for small magnitudeearthquakes in the Alps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Philip Rieger – 3.1 - Inorganic and Isotope Geochemistry . . . . . . . . . . . . . . . . .Sulphur reduction processes leading to the formation of the George FisherZn-Pb-Ag deposit, Mt Isa, Queensland, Australia . . . . . . . . . . . . . . . 41

Juan Rodriguez-Zuluaga – 2.3 - Geomagnetism . . . . . . . . . . . . . . . . . . . . . . . . . .Electric currents related to equatorial plasma depletions: New insights fromthe Swarm mission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Marie Schaeffer – 1.5 - Geoinformatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .A Visual Analytics Approach for Assessing Black Box Classification of RemoteSensing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

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Florian Schäfer – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Continuous high resolution gravity measurements at a geothermal field in Nor-thern Iceland . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Max Schanner – 2.3 - Geomagnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Variational estimation of gamma-distributed parameters . . . . . . . . . . . . 45

Lukas Schoppa – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Comparative Evaluation of Multivariable Micro-Scale Flood Loss EstimationModels for Companies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Morgan Tranter – 3.4 - Fluid Systems Modelling . . . . . . . . . . . . . . . . . . . . . . . . .Geochemical Modelling of Sulfate Scalings in Geothermal Systems . . . . . . 47

Carla Valenzuela Malebrán – 2.1 - Physics of Earthquakes and Volcanoes . .Seismic cluster in Central Chile . . . . . . . . . . . . . . . . . . . . . . . . . 48

Lei Wang – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . . . . . . . . .Poroelastic, hydraulic and acoustic responses of porous sandstone to isotropicpressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Katharina Wetterauer – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . .Alpine headwall erosion rates based on 10Be concentrations in supraglacialdebris cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Gregor Willkommen – 2.7 - Near-Surface Geophysics . . . . . . . . . . . . . . . . . . . . .Radio magnetotelluric survey of the Quaternary Neualbenreuth maar in theWestern Bohemian Massif (Germany) . . . . . . . . . . . . . . . . . . . . . . 51

Robin Wojcik – 3.5 - Interface Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Age and geomorphological controls on geo-bio successions in a sub-Arcticglacial forefield. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

Huiwen Yue – 3.2 - Organic Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Unravelling the role of lithofacies in controlling organic matter composition inunconventional systems using FT-ICR-MS . . . . . . . . . . . . . . . . . . . 53

Xueru Zhao – 4.3 - Climate Dynamics and Landscape Evolution . . . . . . . . . .A new sediment core from Lake Lago Grande di Monticchio extending backto ca. 29,000 BP: preliminary results . . . . . . . . . . . . . . . . . . . . . . 54

EGU posters:Poster Session 1: 11:00 – 12:00 (odd Poster Numbers)Poster Session 2: 16:30 – 17:30 (even Poster Numbers)

55

Yiming Bai – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Receiver Function Imaging of the Mantle Transition Zone beneath CentralMyanmar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Di Cai – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Mg stable isotopes cycling in the Black Forest at different time scales . . . . 56

Angelica Maria Castillo Tibocha – 2.8 - Magnetospheric Physics . . . . . . . . . .Simulations of the inner magnetospheric energetic electrons using the IMPTAM-VERB coupled model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

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Juan Sebastian Cervantes Villa – 2.8 - Magnetospheric Physics . . . . . . . . . . .Assimilation of multisatellite data using a Kalman filter, a window for a betterunderstanding of the near-Earth environment . . . . . . . . . . . . . . . . . . 58

Jing Chen – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Local earthquake tomography of the southern Puna Plateau . . . . . . . . . . 59

Donovan Dennis – 3.3 - Earth Surface Geochemistry . . . . . . . . . . . . . . . . . . . . .Assessing the temperature sensitivity of frost weathering and erosion in glaciallandscapes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Yajian Gao – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Full-Waveform Inversion for Seismic Velocity and Moment Tensor Solutionsbeneath North Chile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Anne Hartmann – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Does age matter? How hydrological flow paths change through the millennia . 62

H.M. Mehedi Hasan – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Multi-criterial calibration of WGHM in the Ganges-Brahmaputra basin . . . . 63

Matthias Kemter – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Using multi-layer complex networks to understand changes in flood occurrence 64

Nora Koltzer – 4.5 - Basin Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Modeling the effects of regional groundwater flow on deep temperatures inHesse (Germany) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

Henning Lilienkamp – 2.6 - Seismic Hazard and Risk Dynamics . . . . . . . . . . .The role of spatial cross-correlation structures of ground motion fields forseismic risk assessment of spatially distributed assets and infrastructure networks 66

Stefan Mroczek – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Mapping the Moho with ambient noise autocorrelations across a N-S profilecrossing the Bohemian Massif and Eastern Alps (EASI) . . . . . . . . . . . . 67

Livia Nardini – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . . . . . .High temperature shear zone formation around material heterogeneities: effectof boundary conditions during nucleation and transient evolution . . . . . . . 68

Derek Neuharth – 2.5 - Geodynamical Modelling . . . . . . . . . . . . . . . . . . . . . . . . .Numerically modelling the controls of crustal strength on microplate formati-on: application to the São Paulo Plateau microplate . . . . . . . . . . . . . . 69

Temitope Seun Oluwadare – 1.1 - Space Geodetic Techniques . . . . . . . . . . . .Statistical study of Medium-Scale Traveling Ionospheric Disturbances (MS-TIDs) characteristics with GPS network over at North African region. . . . . . 70

Mengdi Pan – 3.1 - Inorganic and Isotope Geochemistry . . . . . . . . . . . . . . . . . .Changes of permeabilities as a result of Hydrate Dissociation in Sand-ClaySediments from Qilian Mountain Permafrost, China . . . . . . . . . . . . . . 71

Johannes Petereit – 1.3 - Earth System Modelling . . . . . . . . . . . . . . . . . . . . . . . .Analysis of ocean tide induced magnetic fields — Climate trends and theremarkable role of shelf regions . . . . . . . . . . . . . . . . . . . . . . . . . 72

Daniel Rasche – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Empirical approaches for the depth-scaling of CRNS-derived soil moisture timeseries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

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Marisa Repasch – 4.6 - Geomorphology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Timescales of leaf wax biomarker transport and preservation in alluvial riversystems: Rio Bermejo, Argentina . . . . . . . . . . . . . . . . . . . . . . . . 74

Heike Richter – 4.2 - Geomechanics and Scientific Drilling . . . . . . . . . . . . . . . .Seismic surveying to explore the transition zone around caverns in salt rocks . 75

Nivedita Sairam – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Hierarchical Bayesian approach for parameterizing flood damage model forEurope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Shubham Sharma – 2.1 - Physics of Earthquakes and Volcanoes . . . . . . . . . .Radial anisotropy across Northeastern and Northwestern Himalaya . . . . . . 77

Svenja Steding – 3.4 - Fluid Systems Modelling . . . . . . . . . . . . . . . . . . . . . . . . . .Potash salt composition governs the formation of geogenic caverns . . . . . . 78

Tania Toledo – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Passive seismic monitoring at the Los Humeros geothermal field, Mexico: pre-liminary results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Violeta Veliz – 4.1 - Lithosphere Dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Upper-plate normal faulting on the island of Kythira and its relation to theHellenic subduction-thrust faulting . . . . . . . . . . . . . . . . . . . . . . . 80

Felipe Vera – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Multi-Array Back-Projection as a High-Resolution approach: Application tothe 2007 Mw 7.7 Tocopilla and 2018 Mw 7.5 Palu earthquakes . . . . . . . . 81

Christian Wenzlaff – 4.8 - Geoenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Controlling parameters of a mono-well high-temperature aquifer thermal ener-gy storage in porous media, northern Oman . . . . . . . . . . . . . . . . . . 82

Luzie Wietzke – 4.4 - Hydrology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Comparative analysis of scalar upper tail indicators . . . . . . . . . . . . . . . 83

EGU talks:EGU talks Session 1: 09:30 – 11:00EGU talks Session 2: 14:00 – 14:35

85

Nasim Karamzadeh – 2.1 - Physics of Earthquakes and Volcanoes . . . . . . . . .Source array configuration and applications in crustal structure studies . . . . 86

Jianli Ma – 3.4 - Fluid Systems Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Potentials for Power-to-Gas based subsurface energy storage in China . . . . . 87

Alexandra Mauerberger – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Scandinavian Lithosphere Structure derived from Ambient Noise and SurfaceWaves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Johanna Menges – 4.6 - Geomorphology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .High sediment export from a trans-Himalayan semi-desert driven by late Ho-locene climate change and human impact . . . . . . . . . . . . . . . . . . . 89

Jannes Münchmeyer – 2.4 - Seismology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Improving magnitude scale consistency through boosting tree regression and3D source correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Page No. viii

Cameron Spooner – 4.5 - Basin Modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Mass distribution across the Alpine lithosphere - Results from a gravity cons-trained model of the Alps and their forelands . . . . . . . . . . . . . . . . . . 91

Irina Zhelavskaya – 2.8 - Magnetospheric Physics . . . . . . . . . . . . . . . . . . . . . . . .A combined neural network- and physics-based approach for modeling theplasmasphere dynamics during extreme geomagnetic events . . . . . . . . . . 92

PICOPICO talks: 09:30 – 11:00PICO Presentation 1: 11:00 – 11:30PICO Presentation 1: 11:30 – 12:00 93

Joana MacLean – 3.7 - Geomicrobiology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Microbiology of the terrestrial ‘plastisphere’ - enrichment and characterizationof plastic-associated microbial communities . . . . . . . . . . . . . . . . . . . 94

Leonie Pick – 2.3 - Geomagnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Magnetic Field Characteristics Observed on the Ground Reliably Classify His-torical Geomagnetic Storm Drivers . . . . . . . . . . . . . . . . . . . . . . . 95

Page No. ix

Page No. x

A0 and EGU posters

Poster Session 1: 11:00 – 12:00 (odd Poster No.)

Poster Session 2: 16:30 – 17:30 (even Poster No.)

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 1

Experimental studies on NH+4 -phengite: Spectroscopic insights on NH+4 in-corporation and NH+4 distribution phengite-fluid at high P and T conditions

Nada Abdel-Hak nada.abdel-hak@gfz-potsdam.de3.6 - Chemistry and Physics of Earth Materials

Nada Abdel-Hak, Monika Koch-Müller, Bernd WunderGFZ Potsdam

Considering the cycle of elements between the Earth´s crust and the deep mantle reservoirs, we areinterested in the volatile element nitrogen as well as hydrogen. Phengite is known to incorporate bothN (in the form of NH+4 molecule, as NH+4 can be incorporated into phengite through substitutingammonium NH+4 for potassium K+) and H (as structural OH group) in its structure; therefore phengiteis of particular relevance when studying the cycle of these elements within the Earth. It has been shownin previous studies on natural and synthetic samples that phengite can incorporate considerableamounts of NH+4 and is stable up to upper mantle P, T conditions (e.g. Mookherjee et al. 2001;Watenphul et al. 2009; Yang et al. 2017). Therefore, the question arises at which P-T-conditionsphengite releases NH+4 within the mantle through subduction of lithospheric slabs. Moreover, in-situstructural and spectroscopic investigations on NH+4 - phengite at different simultaneous P-T conditionsare planned to understand phengite’s breakdown mechanism, the kinetics of the breakdown and theP-T dependence of volatile loss. First preliminary results will be shown. We are also interested inthe distribution of NH+4 between phengite and fluid at mantle conditions. To investigate that, weare performing piston cylinder experiments. The run-products are characterized by XRD, SEM, EMPand ICP-MS. References: Mookherjee, M, Redfern, SAT and Zhang, M (2001) ‘Thermal response ofstructure and hydroxyl ion of phengite- 2M1: an in situ neutron diffraction and FTIR study’, EuropeanJournal of Mineralogy, vol. 13, 545-555. Watenphul, A, Wunder, B, and Heinrich, W (2009) ‘High-pressure ammonium-bearing silicates: implications for nitrogen and hydrogen storage in the Earth’smantle’, American Mineralogist, vol. 94, p. 283–292. Yang, Y, Busigny, V, Wang, Z, and Xia, Q(2017) ‘The fate of ammonium in phengite at high temperature’, American Mineralogist, vol. 102, p.2244–2253.

Page No. 1

Poster Stand No 2 A0 posters: Poster Session 2: 16:30 – 17:30

Present and past microbial signatures in deep sediments of the HartoušovCO2 mofette system, NW Bohemia

Karsten Adler kadler@gfz-potsdam.de3.2 - Organic Geochemistry

Karsten Adler1,5, Mashal Alawi2, Qi Liu2, Horst Kämpf1, Robert Bussert4, Birgit Plessen3,Hans-Martin Schulz1, Dirk Wagner2,5, Kai Mangelsdorf11,2,3GFZ German Research Centre for Geosciences, Sections (1Organic Geochemistry, 2Geomicrobiology,3Climate Dynamics and Landscape Evolution), Potsdam, Germany 4Technische Universität Berlin,Institute of Applied Geosciences, Berlin, Germany 5University of Potsdam, Institute of Earth andEnvironmental Sciences, Potsdam, Germany

A mofette is a natural cold, dry or wet gas vent releasing CO2-rich gases into the atmosphere. TheHartoušov mofette system is located in the northern Cheb Basin (western Eger Rift, Czech Republic).The area is characterized by mantle-derived gas emanations (> 99 % CO2) since the early Pleistocene(Bankwitz et al., 2003). The gas preferentially migrates either dissolved in water or as a free gas phasealong deep-seated faults to the surface (Bräuer et al., 2008). Previous studies of surface near sedi-ments of Holocene and Pleistocene age at Hartoušov showed that ascending CO2-containing fluidsresult in significant lithological and microbiological community changes (Flechsig et al., 2008; Beuliget al., 2015; Liu et al., 2018). Deeper microbial habitats may be indicated by the presumed presenceof underlying CO2-containing fluid trap structures in crustal and sedimentary rocks releasing increasedamounts of gas after seismic events to the surface (Fischer et al., 2017). Nickschick et al. (2015)described the presence of dm- to m-sized cavities in sediments of the open-cast mine Nová Ves II at50 m depth which occur along ascending fluid pathways suggesting potential habitats for CO2-relateddeep microbial life. An increase in methane concentrations at the Wettinquelle (Bad Brambach) witha microbial δ13C signature after swarm earthquakes in 2000 was interpreted as enhanced microbi-al activity stimulated by seismically mobilized CO2 and released hydrogen from granitic basementrocks (Bräuer et al., 2005). In summary, there are indications for subsurface CO2-influenced habitatswhich could act as hotspots for deep microbial life. However, studies investigating such microbialhabitats are still missing for deep mofette systems. In spring 2016 a pilot borehole was drilled byGFZ Potsdam for the PIER-ICDP study „Drilling the Eger Rift“ (DFG Alawi, AL 1898/1) into theHartoušov mofette system. During drilling a CO2 blow-out occurred in about 78 m depth, suggestinga CO2 reservoir in sediments of Early Miocene age (Bussert et al, 2017). In consequence, samplesfrom above, within and below this interval were selected to test whether this interval could host aspecific habitat stimulating a deep CO2-related microbial ecosystem. Here, we present results aboutpast microbial ecosystems and their depositional environment. Conceptually, sedimentological bulkparameters and lipid biomarker signals (n-alkanes, sterenes, hopanoids and glycerol dialkyl glyceroltetraethers GDGTs) are compared with signals of present microbial communities. Such present signalsinclude microbial life marker lipids (intact membrane lipids) and data gained by microbiological ana-lyses such as quantitative PCR and Illumina 16S rRNA gene amplicon sequencing (Liu et al., unpubl.data). The Miocene depositional environment is characterized by a change from a terrestrial to alacustrine setting. Increased abundance of past microbial communities in the terrestrial sediments arerelated to phases of soil or peat formation. The abundance and compound specific carbon isotopiccomposition of the past microbial markers mainly reflect these palaeo-environmental changes. Suchbiomarkers reflect activity of heterotrophic bacteria, of soil bacteria in the terrestrial sediments, andmethanogenic archaea and presumably methane oxidizing bacteria in the lacustrine sediments. Thetransition from the terrestrial to the lacustrine depositional environment marks the detected intervalof increased CO2 concentrations at 78 m depth. In contrast to the past microbial signals, microbial lifemarker lipids were rarely found in the CO2 reservoir. Phospholipid fatty acids from living bacteria areessentially absent. However, some yet unknown intact lipid signals indicating living bacterial biomasswere detected, and compound identification is currently underway.

Page No. 2

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 3

Moment tensors of waste-water disposal induced seismicity in SouthernKansas

Amandine Amemoutou amandine@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Amandine Amemoutou, Patricia Martínez-Garzón, Justin Rubinstein, Grzegorz Kwiatek,Marco BohnhoffGFZ Potsdam, GFZ Potsdam, U.S. Geological Survey, GFZ Potsdam,GFZ Potsdam

Fluid-injection into the subsurface in the frame of reservoir-engineering activities for hydrovarbonand geothermal energy production has resulted in a dramatic increase of induced seismicity duringthe last 10 years. This includes four M>5 earthquakes in Oklahoma and Kansas (US) through thereactivation of previously unknown critically stressed and thus hazardous faults in the basement. Weinvestigate seismic recordings of relocated events with local magnitudes ML in the range [1.9,5.2]from a regional seismic network deployed in southern Kansas since 2014 including 19 broadbandstations and 5 accelerometers. Determination of seismic moment tensors and subsequent refinementwas done employing the hybridMT package (Kwiatek, 2016). HybridMT inversion is based on the P-waves first ground displacement amplitudes from vertical components and provides unconstrained full,deviatoric, and double-couple constrained moment tensors. The results of moment tensor inversionare refined and suppress the influence of local path, site, and sensor effects. In this study, we alsoimplemented the use of the horizontal components, thereby increasing the input data by a factor of3. The refined methodology was tested and tuned on synthetic datasets based on the shear-tensilesource model (Vavrycuk, 2001). This model describes the source kinematics by four fault planeparameters (strike,dip,rake) and a tensile angle representing the fault opening. We find that focalmechanisms from the 3-component inversion are generally consistent with the generated syntheticfault plane parameters, signifying the correct performance of the new approach. Furthermore, momenttensor inversion of several tens of events with already reported focal mechanisms (Rubinstein, 2018)appear to be generally consistent between applied methods. In this contribution, first results fromstatistically significant full moment tensors as well as double-couple solutions from initial ∼ 2,300seismic events are presented and discussed in the context of their spatial and temporal changes withinthe investigated area.

Page No. 3

Poster Stand No 4 A0 posters: Poster Session 2: 16:30 – 17:30

Reanalysis of ring current electron phase space densities using Van AllenProbe observations, convection model, and Kalman filter

Nikita Aseev naseev@gfz-potsdam.de2.8 - Magnetospheric Physics

Nikita Aseev, Yuri ShpritsGFZ Potsdam, University of Potsdam, UCLA

Models of ring current electron dynamics unavoidably contain uncertainties in boundary conditions,electric and magnetic fields, electron scattering rates, and plasmapause location. Model errors canaccumulate with time and result in significant deviation of model predictions from observations. Dataassimilation offers useful tools which can combine physics-based models and measurements to decreasemodel uncertainties. Data assimilation has been extensively used in radiation belt physics, but only afew studies have been devoted to its applications to the dynamics of the ring current. In this study,we perform a systematic analysis of the performance of the Kalman filter applied to a log-transformedconvection model of the ring current electrons and Van Allen Probe data. By using synthetic data,we show that the Kalman filter is capable of correcting errors in electron lifetimes and boundaryconditions. We demonstrate that the reanalysis retains features which cannot be fully reproduced bythe convection model such as storm-time earthward propagation of the electrons down to 2.5 Earth’sradii. The Kalman filter can adjust the model to satellite measurements even in the regions where dataare not available. Inspecting the innovation vector, we show that model errors grow with increasingradial distance and enhanced geomagnetic activity. The results of this study demonstrate that dataassimilation can improve the performance of ring current models, better quantify model uncertainties,and help deeper understand the physics of the ring current particles.

Page No. 4

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 5

Analysis of microseismicity framing MW > 2.5 earthquakes at The Geysersgeothermal field, California

Stephan Bentz bentz@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Stephan Bentz, Patricia Martínez-Garzón, Grzegorz Kwiatek, Georg Dresen, Marco Bohn-hoffGFZ Potsdam

Preparatory processes accompanying or leading to nucleation of large earthquakes have been observedat both laboratory and field scale, but the precise conditions favoring them are still largely unknown.Here, we generated high resolution seismicity catalogs framing the occurrence of 20 MW > 2.5 earth-quakes at The Geysers geothermal field in California with the purpose of investigating if earthquakesoccur suddenly in the reservoir or as part of a larger failure process. For each sequence a seismici-ty catalog of the 11 days framing the mainshock is created. Our 20 selected sequences adequatelysample the entire reservoir depth range, temporal periods with high/low injection rates and differenttectonic settings within the field. We find a significant correlation between seismic activity displayedby the different earthquake sequences and their location within the reservoir. Sequences located inthe northwestern part of The Geysers show increased seismic activity and low b-values. While thesoutheastern part is dominated by decreased seismic activity and higher b-values. Periods of high in-jection coincide with high b-values, and vice versa. These observations most likely reflect 1) changesin differential stress across the field and 2) changes in localization and distribution of damage. Halfof the analyzed sequences exhibit no change of the seismicity rate in response to the large event, butrather displaying clear signs of a collocated smaller earthquake right before the onset of the mainrupture, suggesting that small earthquakes spontaneously grow into or trigger larger events.

Page No. 5

Poster Stand No 6 A0 posters: Poster Session 2: 16:30 – 17:30

Sensitivity and stability analysis of coda quality factors at The Geysersgeothermal field, California

Aglaja Blanke a_blanke@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Aglaja Blanke, Grzegorz Kwiatek, Patricia Martínez-Garzón, Marco BohnhoffGFZ Potsdam, GFZ Potsdam and FU Berlin, GFZ Potsdam, GFZ Potsdam and FU Berlin

Over 700 induced seismic events recorded between June 2009 and March 2015 at different parts ofThe Geysers geothermal field, California, are used to estimate local S-wave coda quality factors (QC).Recorded by the 31-station short-period Berkeley-Geysers Seismic Network, the events have durationmagnitudes 1 < MD < 3, depth ranges of 1 and 4 km, and epicentral distance ranges of 0.7 to 19 km.We apply, the coda analysis technique of Phillips (1985) to find QC . Using a sequence of overlappingtime windows, the average Power Spectral Density (PSD) of the coda is calculated. We extract thesignal amplitudes at fixed octave-width frequency bands, measure their decay with time and fit forQC(f ) estimates with associated uncertainties. We investigate the sensitivity of the QC(f ) results todifferent input parameters, including lapse time, magnitude range, moving window width, total codalength and seismic-sensor components. The choice of quality criteria – signal-to-noise ratio (SNR)and coda Q uncertainties – are found to be most sensitive factors. Testing different window lengthsand lapse times result in relatively small variations of QC(f ). The final, highest-quality mean coda Qestimates are further tested in the context of their spatio-temporal behavior in the reservoir. We findthat distance and azimuthal dependence of mean QC(f ) are related to the observed crack-inducedreservoir anisotropy, lithological, and structural features. At the NW Geysers about 50 % larger meanQC(f > 40Hz) estimates are obtained compared to the SE. In contrast, geothermal production ratevariations, analyzed for a tight cluster in the NW, do not influence the QC(f ) estimates. Moreover,we compare the QC(f ) results with previous estimates of direct S-wave quality factors (QD). A matchfor our QC results at 7 Hz center-frequency with QD estimates is observed. However, QC estimatesshow lower scattering and thus higher stability.

Page No. 6

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 7

Can flood intensity be approximated from current satellite-based watermasks?

Fabio Brill fbrill@gfz-potsdam.de4.4 - Hydrology

Fabio Brill, Heidi KreibichGFZ Potsdam

Currently available flood masks derived from satellite imagery have numerous flaws which hinderthe extraction of water depth – which is the single most important input variable for flood damagemodels. Although attempts to compute water depth exist in the scientific literature (e.g. Zwenzner& Voigt 2009), these procedures are still regarded unreliable, especially outside of gauged basins.However, depending on the region, hazard parameters (depth, duration, velocity) exhibit a certaindegree of collinearity, so that damage estimates may be based on several impact metrics or proxies. Itis therefore worthwhile to investigate the possibility of deriving a flood-intensity proxy metric, whichcan be used in the absence of exact water depth measurements. For this task, it is envisaged to explorethe potential of multi-temporal mapping in combination with DEM derivatives. Potentially, the floodmasks can be enhanced by the information content of the actual SAR backscatter. Mean, variance,and minimum intensity over the entire event seem to yield information about the duration and flowcharacteristic. Flooded locations as detected by satellites were extracted from a regular DEM, as werethe corresponding Height Above Nearest Drainage (HAND), and multiple Topographic PositioningIndex (TPI) rasters. The study is conducted for the northern coast of Peru, where a variety ofreference flood maps from the Copernicus Emergency Mapping Service (EMS) and surveyed damagesto buildings from a severe El Niño event 2017 are available. Since affected buildings are mapped,we also defined affected spots by computing convex hulls around all affected buildings within aneighbourhood. In this case it is important to separate regions which were affected by fluvial floodsfrom those damaged by heavy rain or ponding water. The critical decision is the maximum distanceto consider as a group. We currently define groups by a clustering algorithm on coordinates, but thismight neglect heterogeneous processes on small spatial scales. The possibilities and limitations of theapproach are discussed. *Zwenzner, H. & Voigt, S. (2009): Improved estimation of flood parametersby combining space based SAR data with very high resolution digital elevation data. Hydrol. EarthSyst. Sci., 13, 567–576.

Page No. 7

Poster Stand No 8 A0 posters: Poster Session 2: 16:30 – 17:30

Evolution of stressed fractures associated with fluid-rock interactions

Chaojie Cheng chaojie@gfz-potsdam.de4.8 - Geoenergy

Chaojie Cheng and Harald MilschGFZ Potsdam

Chemical reactions between geothermal fluids and reservoir rock minerals are time-dependent pro-cesses leading to an irreversible impact on the fracture aperture evolution, where pressure solutionat propping asperities results in a decrease of fracture aperture, while free-face dissolution at thefracture walls enlarges the void space of the aperture. To investigate the effects of these coupledprocesses on the transport properties of fractured rock, an intermittent flow-through experiment hasbeen conducted over 137 days under hydrostatic confining pressures of 10 and 30 MPa with a porepressure of 1 MPa at a temperature of 140 ◦C. A monomineralic rock (Fontainebleau sandstone),composed of > 99.5% quartz and with a nearly impermeable rock matrix was selected. A tensile frac-ture along the central principal axis of the sample core was artificially produced and the two halveswere assembled with a pre-offset of 0.75 mm. Pre- and post-experiment µCT scans at atmosphericconditions illustrated the geometrical morphologies of the initial and final fracture aperture beforeand after the flow-through experiment, respectively. Permeability was measured each time after flowwas stopped for time intervals of 8 and 16 days, respectively. Before each permeability measurement,the effluent was continuously sampled from the outlet capillary with a sub-sample fluid volume of 0.5ml to measure the silicon concentration. The peak concentration among the respective sub-samplesrepresented the fluid’s composition within the fracture and indicated an ion diffusion process. Thetheoretically dissolved amount of quartz as accounted for by PHREEQC (1.73 mmol/l at 140 ◦C)was significantly smaller than the measured total silicon concentration of the effluent (approximately10 mmol/l), revealing that pressure solution dominates the dissolution process. Confining pressureand the duration of stagnant flow showed no impact on silica concentration, inferring that chemicalequilibrium was reached rapidly. Pressure solution, consequently, thereby is confined. In addition, itshowed that fracture permeability remained approximately constant throughout the experiment. Insummary, it is implied that the silicon concentration of the surrounding fluid increased mainly dueto the pressure solution. The dissolution and diffusion of quartz (silicon) within the water film bet-ween the stressed contacting asperities would then be restricted by the evolving fluid concentration,alleviating pressure solution-induced fracture closure.

Page No. 8

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 9

2D Magnetotelluric imaging of Northwest Venezuela.

José Cruces-Zabala jcruces@gfz-potsdam.de2.7 - Near-Surface Geophysics

J. Cruces-Zabala, O. Ritter, U. Weckmann, K. Tietze, M. SchmitzGFZ-Potsdam, Free University Berlin, Potsdam University, Venezuelan Foundation for SeismologicalResearch

The geodynamic situation of northwestern Venezuela is conditioned by the expulsion of the NorthAndean Block (NAB), and the deformational structures related to the Caribbean – South Americaplate interactions. The most prominent feature is the 100 km wide Mérida Andes (MA) that reachfrom the Colombian border to the Caribbean coast over more than 500 km. We present the analysisof a magnetotelluric (MT) profile acquired at 72 broadband sites along a 240 km long profile withstation spacing between 3 and 5 km across the central part of the MA, including the sedimentaryMaracaibo (MB) and Barinas-Apure (BAB) basins. Phase Tensors (PT) are more consistent with1D/2D dimensionality north and south of the MA, in MB and BAB basins, with low skew angle (β)values and induction vectors showing low variation on direction or magnitude. The 2D structures werewell recovered and their depths correlate well with geological structures. Both sedimentary basins (MAand BAB) show the presence of resistive bodies, not correlated with surface geology, possibly relatedto oil reservoirs, as well as evidence of deformation. Strike directions and dimensionality of the MAseem to be highly influenced from a conductive body east of the profile, as far as 30 km offset tothe profile. Local 3D effects were corrected by means of stations selection and forward modelling,however more regional effects need to be further studied by more detailed 3D investigations.

Page No. 9

Poster Stand No 10 A0 posters: Poster Session 2: 16:30 – 17:30

Deposition and retention of meteoric 10Be in river terraces of an activemountain belt during the Holocene

Kai Deng kdeng@gfz-potsdam.de3.3 - Earth Surface Geochemistry

Kai Deng, Hella Wittmann, Meng-Long Hsieh, Shouye Yang, Friedhelm von BlanckenburgGFZ Potsdam, Tongji University, National Chung Cheng University, Freie Universität Berlin

Cosmogenic meteoric 10Be is produced in the atmosphere and then scavenged by rainfall and dustto the Earth’s surface, where it accumulates in soils by binding to particles. When pH values are >5,meteoric 10Be is almost completely retained on soil particles, and commonly used to quantify soil andsurface ages, or trace soil movement across landscapes. Meteoric 10Be can also be coupled with stable9Be that is released during rock weathering, and rates of erosion and weathering over timescalesof 103 − 105 yrs can be quantified by 10Be/9Be ratios. A prerequisite for all these applications ishowever the knowledge of the 10Be depositional flux to Earth´s surface. Although previous efforts,including large-scale general atmospheric circulation modelling (GCM) and local-scale observationsfrom 10Be inventories in dated soil profiles, have advanced our understanding on 10Be depositionover different timescales, uncertainties in deposition and retention of meteoric 10Be remain due toits complicated distribution pattern in the atmosphere and in soil. In this case, a well-constrained,site-specific depositional flux will make meteoric 10Be a more robust proxy of Earth surface processesat sites of scientific interest. In this study, we focus on an active mountain belt, Taiwan Island, whereEarth surface processes are extremely dynamic and rapid due to active tectonics and frequent typhoonattacks. Applying the meteoric 10Be/9Be system here in combination with a depositional flux derivedfrom GCM has yielded reasonable denudation rates that are consistent with estimates from otherindependent methods. Even so, knowing the prevailing long-term 10Be depositional flux is critical forquantifying the Earth surface processes more precisely in this environment. We therefore measured10Be inventories from depth profiles of three terraces across Taiwan Island, with sampling depths ofup to 6.2m and radiocarbon-derived depositional ages ranging between 3.6 and 9.3 cal. kyr BP. Ingeneral, 10Be concentrations decrease with depth in two profiles, approaching values inherited fromoriginal upstream materials during terrace deposition, but gradually increase in the lower ∼ 2m of theyoungest profile, potentially indicating incomplete retention by chemical dissolution. The total 10Beinventories in the three profiles range from 2.3 − 8.4 × 109at/cm2. Correcting these inventories for10Be inheritance and for partial loss of particulate-bounded Be, the resulting 10Be depositional fluxesare about 40%-60% of modeled values derived from GCM. We then evaluate the potential causesfor the deviation of our measured 10Be depositional flux to the GCM-derived flux, including surfaceerosion, overestimated depositional ages, and temporal changes of 10Be production rates. Differentpossibilities may explain the deficit for each terrace and thus reconcile our measured depositional fluxwith the modelled value. We suggest that the 10Be depositional fluxes derived from these terraceprofiles provide a lower limit for the depositional flux in Taiwan Island, pending better constraints onterrace depositional history, 10Be retention and surface erosion. Our study shows that an improvedunderstanding of long-term meteoric 10Be deposition and all associated uncertainties is necessary inorder to apply meteoric 10Be accurately for inventory dating and constraining quantitative rates ofEarth surface change.

Page No. 10

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 11

Asymmetric Rift Evolution: Geodynamic Modeling of the East African RiftSystem

Maximilian Döhmann doehmann@gfz-potsdam.de2.5 - Geodynamical Modelling

Maximilian Döhmann, Sascha Brune, Simon Riedl, Anne Glerum, Manfred StreckerGFZ Potsdam, University of Potsdam

Asymmetric rift evolution is well known to play a major role for many past and present day riftsystems by governing basin geometry, topography evolution, and sedimentation patterns. Complex,time-dependent, asymmetric rift geometries are observed throughout the East African Rift system andare well documented for instance in the Main Ethopian Rift, the Kenya Rift, and the Malawi Rift. Inthis study, we conduct 2D geodynamic models employing the finite element software ASPECT (Ad-vanced Solver for Problems in Earth’s ConvecTion) by using visco-plastic rheologies, mesh-refinementand a free surface. The presented models comprise a 500 km times 160 km box and consist of fourlayers: upper crust, lower crust, lithospheric and asthenospheric mantle, each with its own rheolo-gical parameters. Laterally, we prescribe extension by applying constant horizontal velocities. Withrespective inflow at the model base, volume conservation is achieved. This setup allows to reproduceprevious modeling results of asymmetric rift development, albeit at much higher resolution of locallyup to 250m. The goal of this study is to link individual geological and geophysical observations fromthe East African Rift within a modeling framework that covers the relevant parameter space in termsof rift velocity, crustal thickness, and material properties. Comparing to available field and geophy-sical data, we find that the geodynamic models reproduce the first order asymmetry of faults andthe subsequent evolution of many rift segments within the EAR: Starting with a single border faultand flexure of the hangingwall crust, followed by antithetic faulting and increasing upper-crustal faultactivity in the basin center. Basinward localization is accompanied by deactivation of the main borderfaults. The pronounced asymmetry of early rift stages is lost during the evolution. Results provideimplications for syn-rift basin evolution, proximal rifted margins and tectonic heat flow, which maygovern carbon maturation.

Page No. 11

Poster Stand No 12 A0 posters: Poster Session 2: 16:30 – 17:30

Numerical investigation of hydraulic stimulation and related induced seis-micity in Pohang fractured geothermal reservoir, South Korea

Márton Pál Farkas farkas@gfz-potsdam.de4.8 - Geoenergy

Marton Pal Farkas, Hannes Hofmann, Günter Zimmermann, Arno ZangGFZ Potsdam, University of Potsdam

In this study, we investigate hydraulic fracturing and hydro-shearing of pre-existing natural fractures incrystalline rock due to hydraulic stimulations at the Pohang Enhanced Geothermal Site in South Korea.Experimentally, several hydraulic stimulations have been conducted at the site in two wells, PX-1 andPX-2. In contrast to the conventional stimulation program, we focus on two distinct applications. First,we concentrate on the stimulation that was performed in well PX-2 in February 2016. The other one isthe flow rate controlled cyclic soft stimulation experiment which was conducted in well PX-1 in August2017. We use the commercial code FracMan that enables studying dynamic hydro-mechanical coupledprocesses in three dimensions using finite element method. These processes are used to simulatestress and pressure redistributions at fractures during hydraulic stimulation to understand changes infracture aperture and thus permeability. FracMan simulates hydraulic fracturing by generation andpropagation of tensile fractures based on an injection–leak-off volume relationship. Both tools arecombined with the investigation of main characteristics of induced seismicity such as spatial evolutionof events and their moment magnitude in relation to injected fluid volume. Preliminary results suggestthat propagation of hydraulic fractures and hydro-shearing at a sub-surface fault near the stimulatedboreholes can explain the pressure curves and the observed microseismic events. The reservoir modelallows different injection strategies to be tested for the design of an optimal stimulation procedure.Ahead of future field applications of cyclic soft stimulation this methodology can be readily appliedat other sites.

Page No. 12

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 13

An integrated 3D model of the South American upper mantle

Nils-Peter Finger finger@gfz-potsdam.de1.3 - Earth System Modelling

Finger, N.-P.1, M. K. Kaban1, M. Tesauro2, C. Haeger1, M. Thomas1,3

1GFZ Potsdam, Potsdam Germany, 2University of Trieste, Trieste, Italy, 3Free University of Berlin,Berlin, Germany

The Amazon Craton and later South American continent was influenced by large-scale geodynamicand tectonic processes over geologic times. Since seismic methods are more sensitive to temperaturethan compositional variations and gravity data allows to decipher density perturbations, integratedgeophysical modelling is the key to understand the complex interaction of these processes. We presentan integrated 3D model of density, temperature and compositional variations for the South Americanupper mantle. First, crustal effects had to be removed from the observed fields to receive residualtopography and mantle gravity. A new crustal model based on available seismic and geologic datawas used to calculate the crustal fields. The model also contains a newly compiled density modelof the sedimentary cover providing distinct density depth relations for the sedimentary basins of theSouth American continent. In addition, the effect of deep mantle density variations was removed fromthe residual gravity field and topography based on global dynamic models. In an iterative approach,temperature variations in the upper mantle were calculated based on seismic velocity variations fromseismic tomography and mineral physics equations. Initially, a uniform juvenile composition of theupper mantle was assumed. After the gravity and residual topography data were corrected for effectsrelated to calculated temperature variations, the residual fields were inverted for composition relateddensity perturbations. Based on these perturbations, the initial composition was altered towardsa composition depleted in Fe and used as new input for the model. This iterative approach wasrepeated until convergence was reached. The resulting models provide an unprecedented image of thestructure of the South American upper mantle. Contrary to expectations, the Amazon Craton showsa relatively low level of depletion (#Mg less than 90.5). Highest grades of depletion were found in theSao Francisco Craton area (#Mg up to 91.5) but are as well below expectations, pointing to strongtectonic reworking of the cratonic roots over time.

Page No. 13

Poster Stand No 14 A0 posters: Poster Session 2: 16:30 – 17:30

Estimation of Energy reserve at Los Humeros geothermal power plant

Hector Gonzalez michango@gfz-potsdam.de4.8 - Geoenergy

González García H., Huenges E., Francke H.GFZ-Potsdam, TU-Berlin

Los Humeros geothermal field is a power plant located in Mexico which has been working for at least30 years, this implies that the power plant has reached its standardized useful life period. With all datafrom the wells we are going to estimate how much energy is in the reservoir, and at the same time,calculate the amount of energy that has been mined by the electric generation. According to the wells,three periods could be defined. These three periods represent three different stages of production andheat mining. The heat reserve approach will be carried out by the heat in place model. Afterward,with the three periods, we would deduce the heat recovery factor in an empiric way. Furthermore, ourexpectations are that these results help us to understand the importance of the use of geothermalenergy in the Mexican electricity market. These results are going to be included in economic energymodels, with the final goal of design a 100% renewable energy matrix for México.

Page No. 14

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 15

NSO Compounds in Oil-Bearing Fluid Inclusions - Development of A Clean-up Method Suitable for FT-ICR-MS Analysis

Yufu Han yufu.han@gfz-potsdam.de3.2 - Organic Geochemistry

Yufu Han, Mareike Noah, Volker Lüders, Brian HorsfieldGFZ Potsdam, Section 3.2 Organic Geochemistry

Oil-bearing fluid inclusions (FIs) contain key compositional clues as to the generation, migration andalteration events occurring within oil reservoir-carrier systems. To gain access to these compositio-nal clues, a broad range of hydrocarbons from methane to biomarkers have been widely evaluatedfrom occluded oils. However, very little is known about NSO (nitrogen, sulfur, oxygen)-containingcompounds in FIs. In order to use Fourier transform-ion cyclotron resonance-mass spectrometer (FT-ICR-MS) in combination with specific atmospheric pressure ionization techniques to analyze theseheterocompounds the sensitivity of the method needs to be tested, and specialized techniques de-veloped to remove potential contaminants. Different cleaning protocols have been published (e.g.Jones and Macleod., 2000; George et al., 2007) often using strong acid and organic solvents to rin-se non-carbonate minerals. However, none of the published methods were suitable for FT-ICR-MSanalysis, since oil-derived NSO compounds were still detectable in quite high amounts after clean-up.Therefore, a modified cleaning procedure was established based on the protocol published by Georgeet al. 2007. This new protocol involves: using sonication to wash minerals with organic and inorganicsolvent, then washing twice by Soxhlet, followed by collection of second washing solvent as blankfor each sample. To verify the cleanness of the host mineral the final outside rinse, as well as puresolvents such as dichloromethane (DCM) and solvent mixtures were analyzed for comparison. Thecleaned sample is afterwards crushed in a stainless steel cylinder using the action of two insertedmoving stainless steel balls. The finely powdered sample is extracted by Soxhlet. To gain valuableinformation from the small amounts of trapped oil FT-ICR-MS measurements in combination withAtmospheric Pressure Photoionization (APPI) and Electrospray Ionization (ESI) were performed. Fourrepresentative sample from Germany, Tunisia, Pakistan and Mexico with microscopically characteri-zed oil-inclusions in different host mineral have be chosen for the method development and the latercharacterization of occluded NSO compounds namely: DE (quartz), TN (fluorite), PK (quartz) andMX (fluorite). Extraction yields of the four samples range between 56-366 µg/g, PK and TN higherthan DE and MX. Elemental class distributions in the DE, TN and PK FIs oil are dominated byhydrocarbons and oxygen-containing compounds, whereas sample MX is different in that it compri-ses abundant hydrocarbon and S1 species in APPI positive mass spectra. As for ESI negative results,oxygen-containing compounds dominate the compounds class in all samples, especially for the O2 andO3 species. Reference Jones, D., Macleod, G., 2000. Molecular analysis of petroleum in fluid inclusi-ons: a practical methodology. Organic Geochemistry 31, 1163-1173. George, S.C., Volk, H., Ahmed,M., 2007. Geochemical analysis techniques and geological applications of oil-bearing fluid inclusions,with some Australian case studies. Journal of Petroleum Science and Engineering 57, 119-138.

Page No. 15

Poster Stand No 16 A0 posters: Poster Session 2: 16:30 – 17:30

Uncertainties of diffusion models in Opalinus Clay

Theresa Hennig thennig@gfz-potsdam.de3.4 - Fluid Systems Modelling

Theresa Hennig, Michael KühnGFZ Potsdam, University of Potsdam

One of the major issues for future generations is the storage of nuclear waste for more than 1million years. According to current knowledge, deep geological repositories are the safest way to storeespecially high-level radioactive waste over long time periods. Claystones are one of the favouritehost rocks for the geological storage of nuclear waste due to their good sorption properties andlow permeability, which makes diffusion the main transport mechanism. Numerical reactive transportsimulations are applied to assess the long-term safety of a repository. Key to the quantification arediffusion models and the evaluation of their uncertainties. They describe the diffusion of radionuclideswith the diffuse double layer theory and interlayer diffusion between the clay layers. Therefore, theporewater is divided into free porewater and porewater bound in the diffuse double layer as well as inthe intermediate clay layers. Diffusion experiments are made with Opalinus Clay from Switzerland. Themodelling results coincide with the experimental data for neutral species (tritium), anions (chloride)and weak sorbing cations (sodium) using the diffuse double layer theory. The diffusion of strongsorbing cations (caesium) additionally requires interlayer diffusion to agree with experimental data.

Page No. 16

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 17

Experimental investigations on the hydrogen solubility in high saline fluidsunder reservoir conditions

Johannes Hierold hierold@gfz-potsdam.de4.8 - Geoenergy

Johannes Hierold, Peter PilzHelmholtz Centre Potsdam German Research Centre for Geosciences GFZ

Due to the switch from conventional to renewable energies, energy storage systems with capacitiesin the GWh to TWh range will be needed in the future. A storage of such amounts of energy ispreviously possible only in the form of chemical energy. In Germany, the greatest potential for storingchemical energy lies in the geological storage of hydrogen or synthesized methane (syngas). Therefore,the research for providing suitable storage media is of great societal as well as economic interest.While there is marginal need for research on the storage of syngas, there is little experience with thestorage of hydrogen. Although hydrogen has been successfully stored in salt caverns at individual sitesaround the world for some time now, pore storage is still considered unsuitable. The reason for thisis assumed high gas losses through diffusion. However, as shown by the storage of town gas (withH2 contents of 40-67% by volume) in Ketzin / Havelland from 1983 to 1992, the gas losses in apore storage including hydrogen are to be minimized under suitable conditions in such a way that aneconomical storage operation is possible. This is also shown by a field experiment in the frameworkof the UNDERGROUND SUN STORAGE project from 2017. In this case, methane was injected ina pore reservoir with the addition of 10% hydrogen and withdrawn after one year, whereby 82% ofthe H2 could be reacquired. The resulting H2 loss is explained by i) microbially induced conversion(methanation), ii) solution in the pore fluid (cushion gas) and iii) diffusion. Little is known aboutthe relevant physicochemical parameters which determine the interaction between hydrogen, fluidsand rocks under typical reservoir conditions. For example, there is a lack of experimental data forhydrogen solubility in saline formation waters from the typical pressure, temperature and salinityranges for relevant depths. H2 solubilities are important because they are relevant for the diffusionof H2 from a gas reservoir in porous media. This makes them indispensable for both safety andprofitability calculations. In a first step, hydrogen solubilities in synthetic salt solutions with chlorideas anion and sodium and magnesium as cations were determined by using a stainless steel autoclave.The experiments comprise a three-dimensional space with the basic factors concentration, pressureand temperature. Concentrations of 0 to ≤ 5 molar were investigated for a grid with pressures of1 to 250 bar and temperatures of 25 to 100 ◦C. In pure water at 25 ◦C, the results are in goodagreement with the predicted values of the Standard Model (PHREEQC, EOS by Spycher & Reed,1988). However, according to the current state of the evaluation, the solubilities for higher salt levelsat variable pressures and temperatures are more than four times higher than the predictions of thecurrent standard model.

Page No. 17

Poster Stand No 18 A0 posters: Poster Session 2: 16:30 – 17:30

Systematic soil gas studies for volcano-tectonic analyses of the Los HumerosGeothermal Field, Mexico.

Anna Jentsch ajentsch@gfz-potsdam.de4.8 - Geoenergy

Anna Jentsch1,2, Egbert Jolie1, Uwe Altenberger21Helmholtz Centre Potsdam, GFZ German Research Centre For Geosciences,Telegrafenberg, 14473Potsdam, Germany, 2Institute of Earth and Environmental Science, University of Potsdam, 14476Potsdam, Germany

Mexico is known for its excellent geothermal resources. The Trans-Mexican Volcanic Belt (TMVB),is hosting two of the four geothermal production fields in Mexico used for power generation. One ofthem is the Los Humeros Volcanic Complex (LHVC), situated 180 km E of Mexico City in the easternportion of the TMVB. Experiences from the operation of the Los Humeros geothermal field indicatethe existence of a superhot geothermal reservoir with temperatures > 380 ◦C, however, geothermalfluids at such high temperatures could only be used to some extent for energy production, due totheir aggressive physicochemical characteristics. The focus of the study is on the structural control onmigration pathways of hydrothermal fluids to identify and assess hydraulically active (permeable) faultsegments or buried discontinuities along major fault zones. Especially in low permeable reservoirs, faultzone architecture and its permeable structures form primary controls of fluid flow. Techniques for soilgas measurements provide important tools for the qualification and quantification of volcanic gases. Inthis study we present results from the first field campaign in 2017, were 2600 CO2 flux measurementswere taken in an area of 3x6 km based on a regular sampling grid within the caldera. CO2 effluxmeasurements were done by the accumulation chamber technique and show elevated values alongknown faults as well as in areas of unknown structures. Based on these results a large-scale samplinggrid was developed for Micro Gas Chromatography (CO2, N2, O2, CH4, H2, etc.) and alpha-particlespectroscopy (222Rn, 220Rn), which show a correlation to CO2 efflux, although in certain areas somegases have a larger extend in their degassing behavior. Additional work has been conducted on theorigin of geothermal gases. Samples for δ13C notation of degassing CO2 and 3He/4He ratios can bea useful tool for the differentiation of the source of gas. δ13C results give evidence for a magmaticsystem with some contribution from the meta carbonates composing the basement. 3He/4He ratiostend towards a mantle contribution. In addition, soil temperatures were collected in 50 cm depth. Inmost parts, thermal anomalies occur in areas of elevated gas emissions. The goal of our systematicand area-wide approach is to put surface gas emissions and soil gas concentrations in the spatialcontext to the geothermal-volcanic system for a comprehensive understanding of fluid migration inthe subsurface.

Page No. 18

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 19

A high resolution (varved) Holocene record from Arid Central Asia and itspaleo-environmental implications

Julia Kalanke juliak@gfz-potsdam.de4.3 - Climate Dynamics and Landscape Evolution

Julia Kalanke1, Stefan Lauterbach2, Jens Mingram1, Birgit Plessen1, Georg Schettler1, AchimBrauer11GFZ German Research Centre for Geosciences, 4.3 ’Climate Dynamics and Landscape Evolution’,Potsdam, Germany; 2University of Kiel, Leibniz Laboratory for Radiometric Dating and Stable IsotopeResearch, Kiel, Germany

High resolution records enable us to disentangle processes controlling changing sediment depositionwhich are possibly indicative for changes of certain atmospheric circulation patterns. They thus allowto determine the impact of their variation on a freshwater ecosystem. To study the impact of changingdominances of the Westerlies, the Siberian High and the Indian Monsoon during the Holocene, werecovered a sediment record of ∼ 6,25m length from Lake Chatyr Kul, located at 3530m a.s.l. inthe Tian Shan/ Kyrgyzstan. It is the first in this region showing seasonal laminated sediments duringthe late Pleistocene-Holocene. The age model was established using 22 AMS 14C ages, a varve chro-nology and radiometric spectrometry of 137Cs, 241Am and 210Pb. Late Pleistocene deposits containclastic-pyrite varves with sporadically occurring aragonite and vivianite sublayers. The Early –MidHolocene comprises clastic-organic, calcite-clastic and diatom varves. The Late Holocene exhibitsclastic-organic varves with highest sedimentation rates. Changing microfacies structures are accom-panied by changing sedimentation rates, varying lake communities of Diatoms, Ostracods, Daphnia,Caraceae, Chrysophytes and aquatic plants and by changes within the proxy data (e.g. µXRF, TOC).All information combined indicate highly variable environmental conditions with pronounced changesat ∼ 4300 and 2000 cal a BP, possibly indicating a declining Indian Monsoon influence and a combinedcontrol on depositional patterns by climate and human impact after 2000 cal a BP. Further comparisonwith other regional records suggests a dominance of the westerlies for the mid-late Holocene. This isa contribution to the BMBF-funded project CAHOL.

Page No. 19

Poster Stand No 20 A0 posters: Poster Session 2: 16:30 – 17:30

Glacial influence on late Pleistocene paleo-erosion rates in the north-westernHimalaya, India

René Kapannusch rene.kapannusch@gfz-potsdam.de3.3 - Earth Surface Geochemistry

René Kapannusch, Dirk Scherler, Georgina King, Hella WittmannGFZ Potsdam, Freie Universität Berlin, GFZ Potsdam, Université de Lausanne

Cosmogenic radionuclide concentrations in ancient fluvial deposits allow estimating paleo-erosionrates and reconstructing the response of landscapes to climatic perturbations. In partly ice-coveredlandscapes however, subglacial-derived sediments can bias these estimates and lead to erroneousconclusions. Here, we combine in situ 10Be-derived paleo-erosion rates, based on sand and pebblesfrom a fluvial fill terrace in the upper Yamuna catchment, with numerical ice flow modelling to quantifythis bias. New luminescence and surface exposure ages suggest that aggradation of the exposeddeposits occurred between 29.9 ± 3.5 ka and 14.8 ± 2.8 ka. During this time, glaciers probably covered∼ 19% of the catchment. Concurrently lower 10Be concentrations in terrace sand, compared to presentday, can be explained by subglacial-derived sediments. This inference is supported by different changesin 10Be concentrations between quartzite and crystalline pebbles, which stem from the unglaciatedLesser Himalaya and glaciated Higher Himalaya, respectively. 10Be concentrations in the crystallinepebbles furthermore suggest higher erosional efficiency beneath the glacier, which is consistent withshallowing of valley gradients in the glacially influenced part of the catchment, possible combinedwith enhanced frost cracking in periglacial areas. The additional sediment production during glacialtimes may have increased sediment supply by ∼ 34% at the sample location and thus contributed tothe aggradation of the Yamuna River.

Page No. 20

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 21

Ocean signals in Earth’s magnetic field (OceanMag-II) - first insights

Kathrin Kirchen kirchen@gfz-potsdam.de1.3 - Earth System Modelling

Maik Thomas, Jan Saynisch, Christopher Irrgang, Johannes PetereitGFZ Potsdam

Due to their ability to store (and release) large amounts of heat, the world oceans are a crucialpart of Earth’s climate system. In addition, the oceans store salt which makes them a good electricconductor. The oceanic conductivity is a function of temperature and salinity. Movements of oceanic,i.e. conducting, water in Earth’s ambient magnetic field result in the induction of characteristicelectromagnetic (EM) fields. Likewise, changes in the external magnetic field will lead to oceanicinduction. Characteristic time scales of the ocean’s dynamics include hours as well as centuries,e.g. tides as well as the overturning circulation. However, the oceans are very hard to observe. Mostmeasurements are only conducted pointwise in time and/or space (e.g. ship based profiling, moorings)or do only cover the upper water layers (e.g. radar satellites, floates). Magnetometer missions, suchas Swarm, give the opportunity to penetrate the sea surface and give an integrated view to theentire water column. If the oceanic induction is sufficiently understood, magnetometer missions couldbe combined with, e.g. altimetry (integrated volume) and gravimetry (integrated mass) to allow anelaborated view of the ocean state. Attempts to measure oceanic induction go back to the middleof the 19th century (e.g. Faraday, 1832). Since then, theory, simulation, and observation of oceanicEM signals have developed dramatically. Today we know that among the oceanographic features, theM2 tide emits the strongest EM signal (±5 nT at sea level, e.g. Irrgang et al., 2016a), but contain alarge static component which is hard to separate from other static or slowly changing EM sources likecrustal magnetization (Hemant and Maus, 2005) or Earth’s background magnetic field (Gillet et al.,2010). The separable, i.e. temporally variable, component is much smaller (±0.5NT at sea level, e.g.Manoj et al.„ 2006). The satellite based remote sensing of magnetic signals began with the launchof Ørsted in 1999 and was followed by CHAMP (2000-2010) and Swarm (launched in 2013). Despitethe sufficiently high precision of Swarm (0.1 nT, Olsen et al., 2007), the much desired detection ofocean circulation EM signals from space is not yet achieved.

Page No. 21

Poster Stand No 22 A0 posters: Poster Session 2: 16:30 – 17:30

Hyperspectral Lithium-Pegmatite Detection – A Case Study Norway, Hoy-dalen

Friederike Klos klos@gfz-potsdam.de1.4 - Remote Sensing

Friederike Klos1, Friederike Körting1, Maria Bade2, Nicole Koellner1, Agnieszka Kuras1,Christian Mielke1, Christian Rogass11Helmholtz Center Potsdam, German Research Center for Geosciences, Telegrafenberg, Potsdam14473, Germany, 2Office for Construction, Environment and Economic Development, MunicipalityWaren (Müritz)

Hyperspectral detection of Li-bearing minerals in Hoydalen, Norway provides a first test case forthe development of a technical solution for a spatially extensive and rapid Lithium prospection.The primary focus of this task is on the mica group minerals and to this end, VNIR and SWIRwavelength region data acquired in the field and in a laboratory will be applied. The combinationof VNIR (400-1000nm) and SWIR (1000-2500nm), using the HySpex system with a line-scanningdetector, provides a complete understanding of the spectral properties of the Li-bearing minerals.First classification tests with the EnGeoMap base algorithm were performed using different libraries(Mielke et al, 2016). For the libraries, the spectral fingerprints of mica minerals based on ASD andlaboratory data were used. Additionally a generic sensor was construct based on the libraries, withthe spectral range between 425 and 2450nm. It includes up to 23 bands and was created to optimizethe classification. Another key aspect will be to focus on minerals not directly associated with lithiumthat can act as indicators of Li. This is important as not all the Li-bearing minerals can be detectedusing the VNIR-SWIR wavelength region data . Field and laboratory measurement and simultaneousacquisition of supplementary geochemical information are the basis for a fully automated software andhardware solution for mapping lithium in real time by airborne measurement. This will be achievedby studying the spectral features of Li-bearing minerals from pegmatite deposits, such as Hoydalen inrelation to their Li content, and by characterizing their spectral variation with respect to similar barrenother minerals. Reference: Mielke et al. (2016): EnGeoMap 2.0 - Automated Hyperspectral MineralIdentification for the German EnMAP Space Mission, Remote Sens. 2016, doi: 10.3390/rs8020127.

Page No. 22

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 23

Imaging Spectroscopy for Mineral Exploration - Case Studies

Nicole Köllner nicolek@gfz-potsdam.de1.4 - Remote Sensing

Nicole Köllner, Friederike Körting, Friederike Klos, Agnieszka Kuras, Christian Mielke, Chris-tian Rogass, Uwe AltenbergerGFZ Potsdam

Imaging spectroscopy has proven to be a fast, environmentally friendly, reproducible, and repeatableanalytical technique that has been increasingly used for rapid, non-destructive and cost-effectivedeposit analyses. Spectroscopy, covering the optical and short-wave infra-red regions across the 400 –2500 nm spectral range, can be used to determine a wide range of materials of economic interest.Imaging spectroscopy in all scales provides state-of-the-art, spatial mineral and element analysis in agrowing field of geological applications. It enables us to visualize the mineral and element compositionof outcrops and mine faces and thus learn about the development of rock-forming and weatheringprocesses that were taking place. Scaling up, satellite imagery can be a powerful tool to pre-assessand characterize deposit types and anomalies from afar, providing information for field geologists andstakeholders alike. Presenting our in-house spectral deposit characterization approach, all scales fromlaboratory to field (HySpex sensors) and satellite imagery (Sentinel-2 and ASTER) can be covered.

Page No. 23

Poster Stand No 24 A0 posters: Poster Session 2: 16:30 – 17:30

Proximal Hyperspectral Outcrop Scanning - A Geological Use Case Study

Friederike Koerting koerting@gfz-potsdam.de1.4 - Remote Sensing

Friederike Koerting, Agnieszka Kuras, Christian Mielke, Nicole Koellner, Friederike Klos,Uwe AltenbergerGFZ, Universität Potsdam

Hyperspectral, proximal outcrop scanning provides state-of-the-art, spatial mineral and element ana-lysis in a growing field of geological applications. It enables us to visualize the mineral and elementcomposition of outcrops and mine faces and thus learn about the development of the rock buildingand weathering processes that are taking place. The hyperspectral imaging sensor system “HySpex”from Norsk Elektro Optikk (NEO) has been used to investigate the influence of rotational measure-ments and single- vs. multi-station measurements on the data and give an idea about the difference ofthe presence of field of view extenders for the data acquisition. The sensor system combines a VNIR(400-1000nm) and a SWIR (1000-2500nm) detector which in combination enables the classification ofthe mineral- and element content of the surface. Based on multi-temporal and multi-station line-scanmeasurements for a REE-outcrop in Ulefoss, Southern Norway, we are able to provide a guideline forhigh-quality, time-effective rotational measurements and give insight into the recommended procedu-res for hyperspectral outcrop measurements. In comparison to the REE-outcrop you will get to knowan application examples from a copper mines in Cyprus.

Page No. 24

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 25

Validation of 1D GIA models in Baltic Sea with sea-level index points

Milena Latinovic milena@gfz-potsdam.de1.3 - Earth System Modelling

Milena Latinovic1,2, Volker Klemann1, Christopher Irrgang1, Maik Thomas1,2

1GFZ Potsdam, 2Frei Universität, Berlin

Sea-level index points (SLIPs) are the only direct measure of sea level during the last deglaciation.Any geological feature that can be related to the formation of the sea level is an SLIP. Relationbetween an SLIP and former sea-level is called indicative meaning. Here we apply statistical methodto the region of Baltic Sea. This region is part of the key area for glacial isostatic adjustment (GIA)research, Fennoscandia. For the purpose of validation, four regional sites of SLIPs are combined.Two from northern Germany and two from Denmark. All indicators are categorized based on thegeomorphological perspective. We apply SLIPs that go back to about 14,000 years before present.Model ensemble with 140 different members differing in upper and lower-mantle values, as well aslithosphere thickness is analyzed and as a result, constrained 1D viscosity is derived for this region.One further aim is to identify regions where a sufficient fit cannot be reached, which might be relatedto an insufficient approximation by a 1D Earth model.

Page No. 25

Poster Stand No 26 A0 posters: Poster Session 2: 16:30 – 17:30

Source Characteristics of Induced Seismicity associated with the Stimulati-on of an Enhanced Geothermal System in Finland

Maria Leonhardt leonhard@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Maria Leonhardt, Grzegorz Kwiatek, Patricia Martínez-Garzón, Marco Bohnhoff, Georg Dre-senGFZ Potsdam, GFZ Potsdam, GFZ Potsdam, GFZ Potsdam, GFZ Potsdam

Enhanced Geothermal Systems (EGS) are used to utilize the heat of the subsurface for geothermalenergy developments. The opening of fluid-flow paths through fluid injection is typically appliedto increase the well performance because EGS reservoirs have low permeability. Unfortunately, thestimulation of the reservoir also leads to induced seismicity. Due to the potential risk and a recentlynegative socio-economic impact of earthquakes that occurred in the close proximity of EGS, it is ofimportance to successfully control induced seismicity during the stimulation of EGS using e.g. softstimulation concepts or near-realtime seismic monitoring to vary stimulation parameters if necessary.In June-July 2018, a stimulation of a 6.1-km-deep geothermal well was performed at an EGS nearHelsinki, Finland where fluid was pumped into crystalline rocks over 49 days. A successful controlof the EGS-related seismicity was possible by using near-realtime seismic monitoring to change thestimulation parameters if necessary and thus to avoid nucleation of Mw 2 event. We reprocessedthe seismic data by analyzing the spatial and temporal evolution of induced seismicity and refinedtheir source parameters. To complete the catalog, we tested different picking strategies to reducethe magnitude-detection threshold down to a moment magnitude of -0.6. Furthermore, we testeddifferent velocity models for an optimization of absolute locations of induced seismicity. Approx. 2000best-recorded events were relocated. We also classified events on their polarity pattern using clusteranalysis to find events with similar focal mechanisms. Therefore, we cross-correlated event waveformsto see whether the waveforms are similar and display comparable polarities, thus focal mechanisms.For events with largest magnitude, we classified clusters which may represent structural features.

Page No. 26

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 27

Quantification of coupled thermo-hydro-chemical processes in the LArgescale Reservoir gas hydrate Simulator by numerical modelling

Zhen Li zli@gfz-potsdam.de3.4 - Fluid Systems Modelling

Zhen Li, Thomas Kempka, Erik Spangenberg, Judith SchicksGFZ German Research Centre for Geosciences, Department 3 - Geochemistry

Natural gas hydrates are considered as one of the most promising alternative fossil energy sources,and thus subject to worldwide research activities. Besides data availability from a few field tests,multiple thermal stimulation experiments including depressurisation and CO2-CH4 exchange have be-en conducted in the LArge scale Reservoir Simulator (LARS) to investigate optimum gas extractiontechnologies from hydrate-bearing sands. These lab-scale experiments provide unique data for nume-rical model calibration and validation, whereby the required numerical tools will be developed withinthe scope of the present study. Using the available data and findings from previous modelling studies,the FEniCS numerical framework will be employed to develop an advanced numerical simulator forquantification of thermo-hydro-chemical processes observed in the LARS experiments. Following thesuccessful model calibration with the help of geophysical data, the developed numerical modellingtools will be used to predict the impact of different thermal stimulation strategies on the efficiencyand sustainability of gas hydrate production.

Page No. 27

Poster Stand No 28 A0 posters: Poster Session 2: 16:30 – 17:30

Differences in sedimentation response to Younger Dryas climate change ina three lake cascade in northern Poland

Christin Lindemann christin@gfz-potsdam.de4.3 - Climate Dynamics and Landscape Evolution

Christin Lindemann, Florian Ott, Michał Słowiński, Markus J. Schwab, Rik Tjallingii, BirgitPlessen, Agnieszka M. Noryśkiewicz, Milena Obremska, Sabine Wulf, Mirosław Błaszkiewiczand Achim BrauerGFZ German Research Center for Geosciences, Max Planck Institute for the Science of Human His-tory, Polish Academy of Sciences, Nicolaus Copernicus University, University of Portsmouth

It is commonly accepted that catchment morphology, type and density of vegetation and the lakebasin bathymetry influence lacustrine sedimentation response to climate change. Knowledge of theselocal influences on climate signal transfer is important for a reliable and robust proxy interpretation.However, it is not straightforward to decipher local influences on the base of only one single sedimentrecord. Therefore, we compare high- resolution sedimentological and geochemical proxies (varve micro-facies, stable isotopes, XRF element scanning) of three neighbouring and partly varved sedimentrecords for their response to the Younger Dryas (YD) climate change. The YD is an ideal timeinterval for an in-depth investigation of proxy responses at major and abrupt climate changes. LakeGłęboczek (JG), palaeolake Trzechowskie (TRZ) and Lake Czechowskie (JC) were formed by glacialhydrodynamic processes, are located within radius of 2 km and thus have experienced the sameexternal (climatic) forcing. The lakes form a cascade-chain and the catchment is mainly composed ofoutwash plain deposits. We investigate the last glacial interglacial transition (13,100 to 11,200 yearscal BP) in all three lakes, allowing us to study the anatomy of rapid climate change on local scale.The sediment records are synchronized through well-defined biostratigraphic boundaries (Allerød/YDand YD/ Preboreal) as well as a common tephra (Askja-S). As expected, the YD triggered distinctsedimentological and geochemical changes in all three lakes. The most obvious change is the cessationof varve preservation at the onset of YD likely caused by increased water turbulence due to strongerwinds. However, the timing of varve cessation differs by up to 160 years between the three records.Recurrence of varve preservation at the Holocene onset is found only in two of the lakes with adifference in timing of 60 years. Another interesting observation is that stable isotope and elementchanges are more pronounced and similar in the three lakes at the YD/Preboreal transition than atthe YD onset. This phenomenon might be explained with the fact that the lakes formed only 3-4centuries before the onset of the YD and thus were not in equilibrium state at the time of climatechange. This study is a contribution to the BaltRap project „WP2: Holocene annually laminated lakerecords“, foundet by the Leibniz Association.

Page No. 28

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 29

Application of a model for point-wise prediction of streamflow statisticsusing climatic and geomorphologic data

Igor Lisac ilisac@gfz-potsdam.de4.7 - Earth Surface Process Modelling

Igor Lisac, Jean Braun, Niel Hovius, Gianluca Botter, Eric Deal, Renee van DongenGFZ Potsdam

Fluvial erosion controls the shape of many mountain belts. Much effort has been put in understandinghow climate affects river discharge and consequently fluvial erosion. In particular, it is important todevelop a better understanding of the link between rainfall variability and mean, and discharge varia-bility and mean in order to build predictable models of long-term geomorphic evolution of mountainbelts, but also to predict the magnitude and frequency of natural hazards. Most existing models rely,however, on the assumption that rainfall characteristics are uniform over a given catchment. Thisis clearly not the case for many mountainous catchments which are affected by orographic effect orfor catchments much larger than the average storm size. The main focus of the work presented hereis to overcome these limitations, and to improve current models of the relationship between rainfalland discharge characteristics. Ultimately, our work can be used to predict how these forcings affecterosional processes characterized by a threshold. We have used the same stochastic, analytical modelas Deal [1] and developed by Botter et al [2]. An analytical expression, used in the model for theprediction of discharge probability density function, is defi ned by four physically based parametersthat are the mean rainfall depth, the frequency of flow producing rainfall events, the coeffi cient andthe exponent describing the discharge recession equation dQ/dt = aQb, which are estimated usingonly climatic and geomorphologic data.

Page No. 29

Poster Stand No 30 A0 posters: Poster Session 2: 16:30 – 17:30

Magnetic mineral diagenesis in the Black Sea - from lacustrine to marine

Jiabo Liu jiabo@gfz-potsdam.de4.3 - Climate Dynamics and Landscape Evolution

Liu Jiabo1, Norbert Nowaczyk1, Helge Arz2

1GFZ Potsdam, 2Leibniz Institute for Baltic Sea Research Warnemünde, 18119 Rostock, Germany

Magnetic minerals are sensitive indicators of sedimentary redox conditions and of changes in thoseconditions throughout time. Knowing the diagenetic alteration of magnetic minerals in sediments iscrucial for the interpretation of their environmental magnetic as well as paleomagnetic records. TheBlack Sea was an isolated fresh water lake during the last glacial and turned into a marginal sea aftergetting connected to the Mediterranean Sea at about 8.3 ka. In order to investigate the diagenesis ofmagnetic minerals in the associated changing hydrological conditions, core MSM33-55-1 recoveredfrom the southeast Black Sea was subjected to detailed rock magnetic and electron microscopy inves-tigations. The younger part of core MSM33-55-1 was continuously deposited since about 41 ka. In theBlack Sea, three hydrological phases, the lacustrine (40.5-17.5 ka), the transitional (17.5-8.3 ka) andthe marine (8.3-0 ka) phases can be recognized for the past 41 ka. Before 17.5 ka, magnetic mineralsare dominantly mixtures of greigite and titanomagnetite in samples with SIRM/χLF ratios largerthan10 kAm-1, or exclusively titanomagnetite in samples with SIRM/χLF ratios less than 10 kAm-1.Specifically, greigite was generally found together with pyrite in crustal aggregates with apparent Lie-segang ring. Between 17.5 ka and 8.3 ka, magnetic minerals were changing from dominantly greigite(17.5 – ∼ 10.0 ka) to probably silicate-hosted titanomagnetite (∼ 10.0 – 8.3 ka). Additionally, abruptincreasing amount of pyrite was indicated after about 14.5 ka. After 8.3 ka, the anoxic Black Seawas a favorable environment for the formation of pyrite framboids. Nevertheless, some silicate-hostedtitanomagnetite/magnetite particles are evidenced in the anoxic marine sediments. Thus, the varyingoccurrences of different varieties of iron oxides and iron sulphides, revealed by this study, demonstratesthe complexities of diagenetic processes in changing environments like in the waterbody of the Blacksea basin.

Page No. 30

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 31

Dome growth during the 2016-2017 eruption sequence at Bezymianny vol-cano, Kamchatka, measured by high-resolution TerraSAR-X and photo-grammetric data

René Mania mania@gfz-potsdam.de2.1 - Physics of Earthquakes and Volcanoes

René Mania, Thomas R. Walter, Marina Belousova, Alexander Belousov, Sergey SenyukovGFZ Potsdam; Institute of Volcanology and Seismology, Far East Branch, Russian Academy ofSciences; Kamchatkan Branch of Geophysical Survey, Russian Academy of Sciences

Lava domes grow by extrusions (exogenous growth) and intrusions (endogenous growth) of viscousmagma often initiating from a central volcanic vent, and are defining the source region of hazardousexplosive eruptions and pyroclastic density currents. Thus, close monitoring of dome building processesis crucial, but often limited to low data resolution, hazardous access and poor visibility, so thatobservations of the style of dome growth and associated morphology changes is scarce. High resolutionSatellite Synthetic Aperture Radar (SAR) enables sustained and accurate detection and quantificationof dome growth related ground motion. Here, we investigated the 2016—2017 eruptive sequenceof the dome building Bezymianny volcano, Kamchatka, with spot-mode TerraSAR-X acquisitionsand complement the analysis with webcam imagery as well as seismic data. The data reveal clearmorphometric changes preceding eruptions and associated with intrusions and extrusions. Pixel offsetmeasurements show seven to nine months of precursory plug extrusion, being locally defined andexceeding 30m of deformation towards the satellite, chiefly without perceptible seismicity. Subsequentthree months of lava dome evolution were characterised by interactions of endogenous and exogenousgrowth. Our data suggest that growth mechanisms were significantly governed by magma supply rateand upper conduit solidification, and that the transition between growth regimes, from intrusive toextrusive, initiated at shallow depths above the base of the dome. The integrated approach contributessignificantly to a better understanding of precursory activity and complex growth interactions atdome building volcanoes, and shows that endogenous and exogenous growth is acting in chorus atBezymianny volcano.

Page No. 31

Poster Stand No 32 A0 posters: Poster Session 2: 16:30 – 17:30

Vertical Seismic Profiling using Distributed Acoustic Sensing technology atthe Groß Schönebeck geothermal research site, NE German Basin

Evgeniia Martuganova evgeniia.martuganova@gfz-potsdam.de4.8 - Geoenergy

Evgeniia Martuganova1, Jan Henninges1, Manfred Stiller1, Klaus Bauer1, Ben Norden1, Char-lotte M. Krawczyk1,2, and Ernst Huenges1,2

1GFZ German Research Centre for Geosciences, Potsdam, Germany, 2Technical University Berlin,Germany

At the beginning of 2017, a high-resolution 3D reflection seismic and a Vertical Seismic Profiling (VSP)data were acquired with the distributed acoustic sensing (DAS) technology at the Groß Schönebeckin-situ geothermal laboratory situated 50 km northeast from Berlin. DAS is a novel technique whichuses a fibre optic cable as an array of sensors for the measurement of particle motion.Geologicalconditions of the research site are typical for a broad part of Northern Europe. Thus, the gainedknowledge can be generalised to the region or applied to the other areas with similar geologicalconditions. The VSP data measurements were recorded in two 4.3 km research wells E GrSk 3/90 andGt GrSk 4/05 using a wireline cable. Wireline type of acquisition leads to the increased noise in thedata and to additional difficulties in data processing. Most likely it is associated with cable slappingand ringing inside the casing. However, understanding the causes of the noise and introduction ofprevention measures are required for the improvement of data quality and further development ofthe DAS wireline acquisition method. In this study processing steps for the elimination of so-calledringing noise are proposed, and the results of their application are demonstrated.

Page No. 32

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 33

What is the effect of spatial dependency in regional flood risk estimation?

Ayse Duha Metin admetin@gfz-potsdam.de4.4 - Hydrology

Ayse Duha Metin, Nguyen Viet Dung, Kai Schröter, Björn Guse, Heidi Kreibich, SergiyVorogushyn, Bruno MerzGFZ German Research Centre for Geosciences, Section Hydrology

Destructive impacts of floods can be reduced by effective flood risk management where flood riskassessment is an essential element. For a given catchment, flood risk is derived by estimating damagesfrom flood events and their associated exceedance probabilities (or return periods). Often, flood riskassessments are based on scenarios with homogeneous return periods throughout the catchment.However, this is not representative for real flood situations, especially for large-scale catchments.Within one flood event, the return periods are spatially heterogeneous among different locations.Therefore, this study aims to understand the effect of spatial dependency in flood risk estimation bycomparing three assumptions on spatial dependence of return period scenarios: (i) spatially dependenthomogeneous (complete dependence), (ii) spatially dependent heterogeneous (modelled dependence)and (iii) spatially independent heterogeneous (complete independence). We use a flood risk chainmodel chain, RFM (Regional Flood Model for Germany), which takes into account all processes fromthe climate forcing through the catchment and river system to damage mechanisms. It enables usto estimate flood risk considering spatially heterogeneous patterns in all processes of the risk chain.This framework is applied to the Elbe basin (Germany) and the results show that, while these threeassumptions give similar damage estimations for small-scale subbasins, the assumptions of complete(in-)dependence lead to large over- or underestimations of the large-scale risk.

Page No. 33

Poster Stand No 34 A0 posters: Poster Session 2: 16:30 – 17:30

Effects of repeated wet-dry events on microbial community dynamics inChilean soil

Lisa-Marie Moskwa lmmoskwa@gfz-potsdam.de3.7 - Geomicrobiology

Lisa-Marie Moskwa1, Nadine Bernhard2, Fabian Horn1, Carsten W. Mueller3, Peter Kühn2,Rómulo Oses4, Thomas Scholten2, Dirk Wagner1,5

1GFZ German Research Centre for Geosciences, Geomicrobiology, Potsdam, Germany; 2Universityof Tübingen, Department of Geosciences, Soil Science and Geomorphology, Tübingen, Germany;3Technical University of Munich, Research Department Ecology and Ecosystem Management, Frei-sing, Germany; 4Centro Regional de Investigacion y Desarrollo Sustentable de Atacama, Universidadde Atacama (CRIDESAT UDA), Copiapó, Chile; 5University of Potsdam, Institute of Geosciences,Potsdam, Germany

Terrestrial ecosystems experience regular changes in water availability. These wet-dry cycles have asignificant influence on soil aggregate formation- and stabilization processes. Besides the physicaleffects on aggregation, the changes in the soil-moisture regime affect microbial activity as well ascommunity structure. Even though drought and rewetting are common events in surface soils, it re-presents physiological stress for microorganisms, as regulating their osmotic pressure demands moreenergy. The soil microbial activity is directly linked to aggregation processes, especially due to theproduction of gluing agents. However, specific taxonomic groups which drive this dynamic responseand act as potential key players remain largely unclear. The aim of this study was to detect thesoil microbial response patterns to moisture changes and to determine the role of microorganismsin aggregate formation- and stabilization processes. Aggregate formation was simulated by repea-ted wet-dry cycles. Surface soil from different climate conditions, ranging from hyper-arid (Pan deAzúcar; ∼ 26◦S), semi-arid (Santa Gracia; ∼ 30◦S), Mediterranean (La Campana; ∼ 33◦S), to humid-temperate (Nahuelbuta; ∼ 38◦S), were collected along the Chilean Coastal Cordillera. Quantificationof bacteria, archaea, fungi, and microbial fingerprinting (DGGE) was used to assess changes in themicrobial community composition. Illumina HiSeq was done to gain a detailed picture of dominantphyla. Shifts in the microbial community composition were related to edaphic parameters and aggre-gate stability. First results indicate that differences in soil types, meaning prevailing edaphic factors,are more drastically compared to the wet-dry events. Overall, we detected three different responsepatterns. (i) In the humid-temperate forests of Nahuelbuta, repeated wet-dry events had a negativeeffect and decreased the microbial cell numbers. But contrary, the community diversity, hence thenumber of different species, increased. It is suggested that the coexistence of species is triggered,which are able to survive in different water-related niches. (ii) Microbial communities in the Medi-terranean region La Campana and semi-arid region Santa Gracia followed similar responses. Here,abundances and community structure remained constant without variations. It is assumed that theprevailing communities already selected for stress-tolerant microorganisms that are able to cope rapidmoisture changes. (iii) In the hyper-arid desert Pan de Azúcar, a positive trend was detected andcell numbers increased with increasing number of wet-dry events. In such extreme environments, mi-croorganisms tend to produce dormant stages to deal with the harsh conditions until environmentalconditions become more favorable. In order to determine potential key players, first results indicatethat even though in Nahuelbuta, La Campana, and Santa Gracia the same dominant phyla are active,different bacterial species respond. Moreover, the response in soils from Pan de Azúcar is already dri-ven by distinct phyla. Overall, the prevailing environmental conditions of the four study sites representa strong ecological filter. Different response patterns are related to a preadaptation of the microbialcommunity to the moisture conditions found in the field. Thus, wet-dry cycles are more stressful formicroorganisms without preadaptation.

Page No. 34

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 35

Global distribution of Equatorial Ionization Anomaly (EIA) crests duringsolar cycle 24

Chinh Nguyen Thai chinh@gfz-potsdam.de1.1 - Space Geodetic Techniques

Nguyen Thai Chinh, Oluwadare Temitope Seun, M.Mahdi Alizadeh and Harald SchuhGFZ German Research Centre For Geosciences and TU Berlin

Equatorial Ionization Anomaly (EIA) is known as the large structure of the Earth with a trough aroundapproximately ±15 degrees of the magnetic equator. This region is considered as the most vulnerablearea for microwave signal propagation. Most of the scintillation activities and ionospheric disturbancesare concentrated in and around this zone. Better understanding the physical characteristics of thisstructure will help ionospheric researchers in dealing with the ionosphere. For decades, many excellentreviews already indicated that the EIA starts developing in the morning at around 9-10 LT, thenmoves poleward in the next about two hours until reaches its highest latitude, where it stays for acouple of hours and finally disappears gradually by early afternoon with equatorward moving. In orderto indicate the morphology of EIA both on spatial and temporal state, a kind of temporal - latitudinalheat Total Electron Content (TEC) maps have been produced for a period of time during solar cycle24 (i.e. from 2007 until 2017) on a global scale. For this purpose, we use both 11-year data of GNSSobservations and the IONEX file. The results of this study show the appearance characteristics of theEIA’s crests by its amplitudes, positions and the time of appearance. To indicate spatial distributions,the mean position of northern and southern crests on a global scale (at every 300 of longitude) andits occurrence time, as well as its amplitude are averaged for the whole 11 years study. For temporalcontributions, we investigate its variations in daily, seasonally, annually and its strong correlationswith the solar cycle activity. In this research it was concluded that the anomaly crests appear around14:30 LT and on a global scale, the mean geographic latitude of the northern and southern crestare around 120N and 6.50S respectively. Its lowest position is at South America (between 600W and900W longitude) with about 00 for the northern and about 180S for the southern crest respectively.The average distance between two crests is around 180 or approximate 2000 km long. At the positionof 300E longitude, most of the time during the period study, the separation of the two crests wasnot clear and in general during this 11-year, these two crests tended to merge into one position.The variation of mean VTEC along the meridian line has a sinusoidal law with the minimum valueat between 300E and 600E (around 14.3 TECU) and maximum value around 1200W and 1500Wlongitude (around 16.5 TECU). With the time variation, like TEC value, the changes of anomalycrests’ amplitudes have a very good agreement (the correlation coefficient is approximate 0.99) withthe solar indices (i.e. Sunspot number and Radio flux F10.7 cm index). In each year, the amplitude ofthe crest in both hemispheres is always got the maximum at equinox months. In the ascending phaseof solar activity (period 2009 – 2013), the amplitude of the crest in autumnal equinox (September –October in the northern hemisphere) is always larger than that in the vernal equinox (March - April inthe northern hemisphere). Conversely, in the descending phase of the solar cycle (period 2007 – 2009and 2014 – 2017), the crest’s amplitude in spring equinox is larger than in autumnal equinox. In thesolar maximum years (2013 – 2014) and solar minimum years (2008 - 2009), the amplitudes of thecrests in both equinox months are equivalent. The general tendency of anomaly crests’ appearance isto move equatorward and appear sooner in the winter months (December, January in the northernhemisphere or June, July in the southern hemisphere). In summer solstice (June, July in northernhemisphere and December, January in south hemisphere) these crests are to move poleward andappear later. For a long-term overview, we can conclude that in the deep solar activity years (2008 -2009), the amplitudes of the crests are minimal (around 30 TECU), the crests’ positions are nearestto the magnetic equator

Page No. 35

Poster Stand No 36 A0 posters: Poster Session 2: 16:30 – 17:30

Acoustic emissions induced by a hydraulic-fracturing experiment at theÄspö Hard Rock Lab: Continuous vs. progressive injection scheme

Peter Niemz peterniemz@gfz-potsdam.de2.6 - Seismic Hazard and Risk Dynamics

Peter Niemz, Simone Cesca, Torsten Dahm, Arno ZangGFZ Potsdam / Universität Potsdam , GFZ Potsdam, GFZ Potsdam / Universität Potsdam, GFZPotsdam / Universität Potsdam

Different fluid-injection schemes were studied under controlled conditions during six in-situ, multi-stage hydraulic fracturing (HF) experiments performed at the Äspö Hard Rock Laboratory (Sweden).At a depth of 410m the fracture growth process from a horizontal injection borehole was investigatedusing induced seismicity detected with continuous and triggered recording systems. We studied thecharacteristics of the induced seismicity resulting from two different injection schemes: conventionalcontinuous and cyclic progressive. The latter is used for fatigue hydraulic fracturing, a method de-veloped to mitigate induced seismicity with potential applications in enhanced geothermal systems.A network of 11 piezoelectric borehole sensors covering a volume of approximately 30 x 30 x 30maround the 28m long injection borehole recorded induced acoustic emissions (AEs). To extract andcharacterize high-frequency AEs, we set up a semi-automatic work-flow for detection, classificationand localization using full waveform techniques. Detection and localization are based on the stackingof characteristic functions and a coherence analysis across pre-calculated travel time grids. To ex-clude false detections we apply a Hidden Markov Models classifier trained on waveform features.Relative magnitudes are calculated using maximum amplitudes across the network. Using this workflow, we were able to increase the total number of AEs in the catalog from 196 events obtainedfrom triggered recordings to more than 3000 events extracted from the continuous recordings. Thisallows a refined study of single HF experiments, as well as single fracturing stages and the accordingrupture process. For the conventional injection experiments the hypocenters are spatially clustered inplanar regions, revealing a main fracture plane. The progressive injection scheme generates a diffuse,but smaller cloud of hypocenters. The maximum magnitude induced by the conventional is largercompared to the progressive injection, though the injected volume was similar. A comparison of thefrequency-magnitude distributions indicates that the b-value is larger for the seismicity induced bythe progressive injection scheme implying an increased number of small events relative to the largeones.

Page No. 36

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 37

Geochemical Characteristics of Lake Sentani, Papua Province, Indonesia

Sulung Nomosatryo snomosa@gfz-potsdam.de3.7 - Geomicrobiology

Sulung Nomosatryo, Cynthia Henny, Herry Kopalit, Rik Tjallingii, Anja M. Schleicher, JensKallmeyer, Dirk WagnerGFZ Potsdam, RC Limnology LIPI Indonesia, Universitas Papua, GFZ Potsdam, GFZ Potsdam, GFZPotsdam, DFZ Potsdam

Tropical lakes have entirely different physical and geochemical characteristics than lakes of temperateclimates. Still, only few studies have investigated tropical lakes, especially water column- and sediment-geochemistry has not received much attention. We present a geochemical study of lake Sentani (2o S).The lake has four separate basins, separated by shallow sills, and a geologically very diverse catchment.The catchment on the north side of the lake is characterized by alluvial, mafic, and ultramafic rocks,whereas the southern part is dominated by limestone and sandstone. We assume that the geochemicalcharacteristics of each basin are distinct from each other. The distinct sediment composition of eachbasin is a direct result of different lithologies in the respective catchment and the bottom waterand pore water chemistry will reflect the different sediment composition. Therefore, our investigationoffers a unique opportunity to study four different tropical lacustrine systems with different catchmentlithology in a single lake. On site we measured water column chemistry, and collected sediment samplesfollowed by chemical analyses of lake and sediment pore water as well as sediment composition atGFZ. Our results show that all four basins share almost identical surface water chemistry and exhibitsub- to anoxic bottom water. However, each basin has a distinct water column stratification pattern,pore water and sediment geochemistry. The reduction-oxidation process of sulfur speciation and therelease ortho phosphate in the monimolimnion zone (anoxic water column) shows that the lake is ameromictic lake. Dissolved sulfide produced by sulfate reduction occurs at the anoxic water columnand the pore water is partially precipitated as pyrite. Remineralization of organic matter and mineraldiagenesis causes variable fluxes of ammonium, K, Mg and Ca from the sediment pore water into thewater column, exhibiting a characteristic pattern in each basin. Covariance correlation analysis basedon detrital mineral composition identifies two groups of basins. Furthermore, the solid-phase and porewater geochemistry results, as well as water column chemistry data, demonstrate the influence ofcatchment lithologies on the geochemical characteristics of the lake’s water column and sedimentchemistry.

Page No. 37

Poster Stand No 38 A0 posters: Poster Session 2: 16:30 – 17:30

Radiogenic and stable Strontium isotopic fingerprints of ecosystem nutrition

Ralf A. Oeser oeser@gfz-potsdam.de3.3 - Earth Surface Geochemistry

Ralf A. Oeser, Friedhelm von BlanckenburgGFZ Potsdam

The conversion and transfer of rock-derived elements like calcium (Ca) and strontium (Sr) throughregolith to plants can be traced and quantified using radiogenic (87Sr/86Sr) and stable (δ88Sr) Srisotope ratios. Radiogenic strontium isotope ratios are widely used to trace sources in environmentalstudies from the soil to catchment scale in order to identify the geologic source of dissolved andbiogeochemical cycled Sr. Although Sr is not a plant-essential nutrient itself, it is widely used asgeochemical tracer for the nutrient Ca. In this context, 87Sr/86Sr ratio is applied as ecological tracerto detect the source and uptake depth of Ca in different ecosystems. Opposite to the 87Sr/86Srratio of single minerals and plants which is not being altered during dissolution or plant uptake,88Sr and 86Sr fractionate upon phase transformation and plant uptake. Alike other stable isotopesystems, changes in δ88Sr from reactant to product are used to observe and quantify processes in theCritical Zone. The Chilean Coastal Cordillera with its steep climate and vegetation gradient rangingfrom arid and sparsely vegetated in the north to humid, forested areas in the south, accommodatesa natural laboratory to determine potentially occurring variations in ecosystem-nutrition strategiesbased on changes in the degree of weathering. In three study sites located in semi-desert (∼ 30◦ S),Mediterranean (∼ 33◦ S), and temperate (∼ 38◦ S) climate zones, we determined the radiogenic andstable Sr isotope composition in bulk bedrock, regolith (comprised of soil and saprolite), and plantsamples. From regolith samples the bioavailable fraction, that is assumed to be representative for soilwater, has been extracted using a sequential extraction method and analyzed in terms of elementconcentration and Sr isotope composition. Results indicate that the bioavailable fraction of soil andsaprolite amounts up to 40% to that contained in bulk regolith but is generally in the order of 0.1 to1%. In Santa Gracia (semi-arid) and La Campana (Mediterranean), the Ca and Sr abundances in thisfraction range from 1 to 10% relative to bulk material, showing a coherent depth-distribution withinsite. In Nahuelbuta (humid), however, Ca and Sr abundances differ by one order of magnitude andshow a different distribution with depth. The biologically available fractions’ radiogenic Sr isotopecomposition of regolith samples is either more (Santa Gracia) or less (La Campana & Nahuelbuta)radiogenic than bulk bedrock and regolith. This implicates that at each site, different minerals arebeing dissolved by weathering and contribute to the soil waters’ Sr isotope ratio. Stable Sr isotopecomposition of bulk bedrock and regolith vary between 0.25 and 0.3%� and do not deviate from bulksilicate Earth’s δ88Sr value. However, the δ88Sr values of the bioavailable fraction deviate up to 0.6%�from that of bulk material. A pattern applies to the three study sites: the higher the degree of chemicalweathering, the higher the absolute difference between bulk regolith and the corresponding bioavailablefraction. In the semi-arid site, most plant samples’ 87Sr/86Sr ratio is alike the bioavailable fractionin regolith, testimony for element uptake from soil waters into plants. However, this observationdoes not hold true for the Mediterranean and humid study site. In these sites, plant samples havea higher 87Sr/86Sr ratio than the bioavailble fraction in regolith. Stable Sr isotopes do fractionatewhilst uptake into plants and upon translocation within plants. However, the magnitude and directionof this fractionation is species dependent.

Page No. 38

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 39

Elasticity and stucture evolution of carbonates at upper mantle conditions

Lea Pennacchioni leap@gfz-potsdam.de3.6 - Chemistry and Physics of Earth Materials

Lea Pennacchioni, Sergio Speziale, Bjorn WinklerGFZ Potsdam, Goethe University Frankfurt

In my PhD work I will focus my attention on the physical properties of carbonate minerals, the majorcarbon carriers in the Earth’s mantle. We have a very deep understanding of the carbon cycle onthe surface of the Earth but little is known about the cycle of carbon in the Earth’s deep interior. Inparticular, the aim of my PhD is the study of the elastic properties of the most abundant carbon-bearing minerals, the carbonates. The focus of my PhD work is on the systematic characterizationof the elastic properties of carbonates as a function of their structure and chemical composition,which is essential to be able to identify their presence and distribution in the lithosphere and uppermantle. In particular, I will investigate the major carbonates such as calcite, aragonite, magnesite,dolomite, siderite and ankerite. I will study mainly natural samples. I will determine the elastic tensorof the carbonates of interest by means of Brillouin spectroscopy. I will perform experiments mostlyon single crystals. However, I will also be involved in the characterization of the elastic propertiesof amorphous carbonates at high pressures can add crucial information (by analogy) about those ofdeep carbonatitic melts formed in the upper mantle. To study the elastic tensor as a function ofthe compositional change it is necessary to supplement the elasticity measurements with an accuratedetermination of the chemical composition of the measured samples. Electron micro probe analysiswill be performed to determine the chemical composition and homogeneity of the samples of interest.I will determine the unit cell parameters and structural properties by single crystal x-ray diffraction.I will perform Brillouin scattering experiments at both ambient conditions, high pressures up to 18GPa and high pressure, high temperature conditions (up to 10GPa and 800K). The experimentalwork will be supplemented by ab initio computations. In detail, I will carry out Brillouin scatteringmeasurements at ambient conditions on a set of three or more platelets of each sample, measuring36 spectra for each platelet, and I will use the acoustic velocities to constrain a set of six or nineelastic coefficients (depending on the symmetry of the material) by least square fit of the Christoffel’sequations. I will then perform high-pressure studies of one sample of each carbonate mineral usingdiamond anvil cell (DAC) as a pressure device and lastly I will conduct experiments simultaneously athigh pressures and high temperatures by means of a modified hydrothermal DAC. I will also measuresingle-crystal x-ray diffraction of the same samples at selected high-pressures to follow their structuralevolution. As final part of my PHD I plan to perform ab-initio DFT calculations of the full elastictensor of all the studied materials in order to compare the two methods, and to have a deeper insightinto the microscopic mechanisms controlling the elasticity anisotropy of carbonate minerals underhigh pressures.

Page No. 39

Poster Stand No 40 A0 posters: Poster Session 2: 16:30 – 17:30

Automatized quality control and moment tensor inversion for small magni-tude earthquakes in the Alps

Gesa Petersen gesap@gfz-potsdam.de2.1 - Physics of Earthquakes and Volcanoes

G. Petersen1,2, S. Cesca1, and the AlpArray working group1GFZ Potsdam, 2Universität Potsdam

With its dense seismological network of more than 600 broadband stations, the European AlpArrayinitiative provides the opportunity to obtain better insights into regional seismicity patterns as well asinto source processes of single earthquakes. While the large number of stations within the AlpArrayenables detailed studies over a broad region, quality control for such a dataset remains a major chal-lenge. We present a new tool dedicated to automated station quality control of dense seismic networksand arrays: The AutoStatsQ toolbox evaluates the quality of waveform data using automatically dow-nloaded data and metadata of selected teleseismic events. Relative gain factors, sensor orientationcorrections and reliable frequency bands for moment tensor inversions are provided for all stations ina chosen time period. The results of the toolbox for the AlpArray seismic network were used to informnetwork operators and integrated into a framework for automated moment tensor inversions for theAlps. We want to discuss the challenges of moment tensor inversions for weak events and presentpreliminary moment tensor solutions for events with magnitudes down to MW 3.5.

Page No. 40

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 41

Sulphur reduction processes leading to the formation of the George FisherZn-Pb-Ag deposit, Mt Isa, Queensland, Australia

Philip Rieger philip.rieger@gfz-potsdam.de3.1 - Inorganic and Isotope Geochemistry

P. Rieger1,2∗, J. M. Magnall1, S. A. Gleeson1,2, A. Rocholl1, R. Lilly31 GFZ Potsdam, Germany; *prieger@gfz-potsdam.de, 2 FU Berlin, Germany, 3 University of Adelaide,Australia

The Proterozoic Mount Isa Inlier hosts several world-class base metal deposits including the GeorgeFisher Zn-Pb-Ag deposit (GF). The most economic deposits are hosted by the carbonaceous, pyritic,late Paleoproterozoic Urquhart Shale (US), which has undergone various stages of deformation. TheUS and GF contain multiple generations of fine-grained pyrite, the origin of which has been debatedby previous workers. In this study we present δ34S values for pyrite associated with GF, obtainedby in situ analysis using secondary ion mass spectrometry (SIMS). The small spot size (< 5 µm)ensured spatially resolved isotopic data were produced for all generations of pyrite. The parageneticallyconstrained δ34Spyrite values provide valuable information about the processes responsible for sulphidegeneration in and around GF. Four generations of pyrite were identified at GF: fine-grained subhedral-spheroidal pre-ore pyrite (py-1); coarse-grained anhedral pyrite associated with ore-stage 1 sphaleriteand galena (py -2); coarse-grained euhedral pyrite associated with ore-stage 2 galena and sphalerite(py-3) and massive anhedral to euhedral pyrite associated with ore-stage 3 pyrrhotite, chalcopyrite,galena and sphalerite (py-4). Coarse-grained euhedral pyrite was also identified in the unmineralised US(py-euh). Whereas pre-ore pyrite (py-1) preserves negative δ34S values (-8.1 to +11.8 %�; n = 186),the ore stage pyrites (py-2, py-3 and py-4) preserve higher δ34S values (+1.9 to +33.3 %�; n = 268).The highest δ34S values are preserved in py-euh (+7.2 to +33.9 %�; n = 189). The negative δ34Svalues (py-1) provide evidence for bacterial sulphate reduction (BSR) of seawater sulphate underrelatively open system conditions. In contrast, the ore-stage pyrites (py-2, py-3 and py-4) may haveformed during more closed system BSR, thermochemical sulphate reduction or sulphate reductioncoupled to anaerobic oxidation of methane. The highly positive δ34S values in py-euh are evidenceof sulphate limitation in a closed system. The overall distribution of δ34Spyrite values from this studyis similar to other un-deformed late Paleoproterozoic sediment-hosted base metal sulphide deposits,thereby providing evidence that common processes were ultimately responsible for sulphate reduction.

Page No. 41

Poster Stand No 42 A0 posters: Poster Session 2: 16:30 – 17:30

Electric currents related to equatorial plasma depletions: New insights fromthe Swarm mission

Juan Rodriguez-Zuluaga juanrz@gfz-potsdam.de2.3 - Geomagnetism

Juan Rodriguez-Zuluaga, Claudia Stolle, Jorge L. ChauGFZ Potsdam, IAP Kühlungsborn

The common understanding of the electric current system associated with equatorial plasma deple-tions (EPD) has been carried out mainly by theoretical studies. Advance in the knowledge of theelectrodynamics of EPDs is essential to comprehend their evolution and day-to-day variability. Inthis paper, we address the most recent findings of field-aligned currents (FACs) related to EPDsas observed by ESA’s Swarm constellation mission. The implemented data set corresponds to si-multaneous measurements of electron density, and magnetic field spanned from 1 December 2013to 31 December 2017. Here we show firstly, that FACs flowing at the edges of large-scale EPDsare interhemispheric rather than anti-parallel about the magnetic equator, as suggested by previoustheoretical studies. Such results agree with an electrostatic regime determined by a hemisphericalasymmetry of the Pedersen conductivity as assessed by empirical models. To the knowledge of theauthors, this corresponds to the first report of the climatology of FACs at the edges of EPDs.

Page No. 42

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 43

A Visual Analytics Approach for Assessing Black Box Classification of Re-mote Sensing Data

Marie Schaeffer marie.schaeffer@gfz-potsdam.de1.5 - Geoinformatics

Marie Schaeffer, Mike Sips, Doris DranschGFZ Potsdam

The complexity of the models, built by today’s machine learning algorithms, impedes humans tointerpret and understand them. As the usage of those models increases – they can be built easily andfast and achieve a high performance even for complex data – the need to understand how they workgrows likewise. We develop a visual analytics approach for assessing black box classifiers so that theapproach is independent of the used machine learning algorithm. To open the black box so far thatwe are able to assess the classification results, we examine input-output-relationships. We use thetraining data set to find prototypes for the single classes in the input data space. Then the prototypescan be used to compare new data with the data that defines the classifier’s behavior. We test ourapplication with a random forest classifier. For training, data from remote sensing for determiningland cover is used.

Page No. 43

Poster Stand No 44 A0 posters: Poster Session 2: 16:30 – 17:30

Continuous high resolution gravity measurements at a geothermal field inNorthern Iceland

Florian Schäfer florian@gfz-potsdam.de4.8 - Geoenergy

Florian Schäfer1, Philippe Jousset1, Jacques Hinderer2, Christian Voigt1, Benjamin Männel1,Kemal Erbas1, Nolwenn Portier2, Séverine Rosat2, Stephan Schröder1, Maren Brehme1, Ar-thur Jolly3, Richard Warburton4, Andreas Güntner1.5

1Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Potsdam, Germany,2EOST, University of Strasbourg, France, 3GNS Science, Wellington, New Zealand, 4GWR Instru-ments Inc., San Diego, USA, 5Institute of Environmental Science and Geography, University of Pots-dam, Germany

For a better understanding of the sustainability of geothermal resources, we want to quantify sub-surface mass changes caused by production and injection of fluids at the Theistareykir geothermalfield in Northeast Iceland. For this purpose, we installed three superconducting gravity meters andtwo spring gravity meters in vicinity to the new geothermal power plant that started operation inOctober 2017. Prior to the Iceland installation, all gravity meters were setup at the gravimetric ob-servatory J9 in Strasbourg for simultaneous side-by-side measurements. The obtained data were usedfor instrumental calibration, comparison of noise levels and tidal analysis. In Theistareykir, three ofour measuring sites are set up close to the geothermal production and injection wells. The fourth siteis located outside the geothermal field, to provide reference measurements that are unaffected by theactivities of the power plant. At each site additional physical parameters, which influence the localgravity signal, are measured. This includes the continuous monitoring of GPS-positions, rainfall, soilmoisture and snow thickness. Moreover, snow weight and snow water equivalent are measured at thesite close to the production wells. Here, we present the results of the unique intercomparison of threesuperconducting gravity meters and two gPhones at Strasbourg and the initial time series obtainedat the geothermal site in Iceland. A preliminary interpretation of the gravity variations with regard tothe geothermal activities and the hydro-meteorological dynamics is given.

Page No. 44

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 45

Variational estimation of gamma-distributed parameters

Max Schanner arthus@gfz-potsdam.de2.3 - Geomagnetism

Max SchannerGFZ Potsdam, Uni Potsdam

In various modeling scenarios one is confronted with parameters that take only positive values (havepositive support). A statistical model for such parameters is presented by the gamma-distribution.However, depending on the likelihood of the parameters, estimation becomes difficult. VariationalBayesian methods provide a framework for problems like this, though analytic calculations are onlypossible for likelihoods which have a conjugate prior. If no conjugate prior exists, numerical approxima-tions have to be employed. We formulate an approach to variational inference for gamma-distributedhyperparameters with arbitrary likelihoods. We then apply this method to the problem of correlationbased modeling of the Earth’s magnetic field and estimate two kernel-hyperparameters, the referenceradius and the scaling factor of non-dipole contributions.

Page No. 45

Poster Stand No 46 A0 posters: Poster Session 2: 16:30 – 17:30

Comparative Evaluation of Multivariable Micro-Scale Flood Loss EstimationModels for Companies

Lukas Schoppa lukas.schoppa@gfz-potsdam.de4.4 - Hydrology

Lukas Schoppa, Heidi Kreibich, Tobias Sieg, Gert ZöllerUniversität Potsdam, Institut für Umweltwissenschaften und Geographie, AG Geographie und Natur-risikenforschung / GFZ Potsdam, Sektion 4.4 Hydrologie / DFG-RTG NatRiskChange

Recent developments in flood risk analysis involve multivariable flood loss estimation models insteadof univariable stage-damage functions. Although the incorporation of additional damage controllingvariables has the potential to improve loss estimations, the predictions are still subject to conside-rable uncertainty. Furthermore, recent research in the field focused on losses experienced by privatehouseholds neglecting the considerable contribution of the business sector to total damages. Theprediction of company flood loss is particularly challenging, as the heterogeneity among differentbusinesses is of considerable magnitude. In this methodological study, we present three state of theart approaches to flood loss estimation for companies that intrinsically quantify the associated un-certainty in their simulations. Based on object-scale loss data (n=1314), we comparatively evaluatethe predictive capacity of random forests, an expert Bayesian network and a Bayesian multilevel betamodel. Company loss data stems from four post-event surveys after major floods in Germany between2002 and 2013 and includes information on hazard intensity, company characteristics and undertakenprecautionary measures. We assess model skill based on the sharpness and reliability of the returnedresponse distributions of relative loss separately for direct damages to building, equipment as wellas to goods and stock. Knowledge about the accuracy of the loss estimates is indispensable, giventhe relatively small number of company loss data and large inter-company variance. The proposedloss estimation models could contribute additional reliability information to conventional flood riskanalysis. Our study aims at revealing strengths and shortcomings of the individual modeling tools,promoting the implementation into management practice in the near future.

Page No. 46

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 47

Geochemical Modelling of Sulfate Scalings in Geothermal Systems

Morgan Tranter mtranter@gfz-potsdam.de3.4 - Fluid Systems Modelling

Morgan Tranter, Michael KühnGFZ Potsdam, University of Potsdam

Hydrothermal resources are often brines and tend to be sensitive in terms of precipitation of mineralswhen the state temperature and/or pressure are altered. This makes them difficult to handle in atechnical sense as scalings may clog the system or even the reservoir within short operation timesof a geothermal plant. Especially sulfate minerals, such as anhydrite and barite, stand out to beexceptionally hard to remove once accumulated, effectively interrupting the process cycle, which isamong the remaining issues still needing to be resolved in regards to its sustainability. We utilisegeochemical models based on the law of mass action in an efficiently coupled setting with PHREEQCand Python to study the dissolution and precipitation behaviour of anhydrite and barite. Factorscontrolling chemistry along the reaction pathway such as thermodynamics, kinetics and pore sizeare consecutively added to the model complexity. Results show that laboratory results can be repro-duced for temperatures up to 150 ◦C and pressures up to 50MPa. Machine learning methods offerpossibilities for a systematic evaluation of input-output patterns of a specific geochemical system.We apply these findings by introducing surrogate models for speed-up, hence making coupling withhydrodynamic transport models feasible. This may contribute to making more reliable spatial andtemporal predictions of scalings and help to mitigate them.

Page No. 47

Poster Stand No 48 A0 posters: Poster Session 2: 16:30 – 17:30

Seismic cluster in Central Chile

Carla Valenzuela Malebrán carlav@gfz-potsdam.de2.1 - Physics of Earthquakes and Volcanoes

Carla Valenzuela, Simone Cesca, Sergio RuizCarla Valenzuela

Seismicity in Central Chile has been characterized in the last decades by the repeated observation ofseismicity of clusters. In some cases seismicity cluster have been discussed as precursors of precededlarge earthquakes. However, most clusters at the Chilean subduction margin did not evolve into majorseismic activity. We identify two spatial seismicity clusters at latitudes 33-36 ◦S, one offshore thetown of Navidad and one inland, close to Vichuquén. Clusters locations are within the Northern partof the rupture area of the 2010 Maule earthquake, and mark the edges of the rupture area of the2010 Pichilemu earthquake doublet. In this study we characterize and discuss hypocentral locations,spatio-temporal migration, magnitudes and inter-event time distributions and moment tensors ofthis recurrent activity, hypothesizing the potential physical possible processes responsible for theiroccurrence. Both clusters are characterized by weak to moderate seismicity and present clear seismicityrate and Benioff strain anomalies, with respect to the surrounding region. The combined analysis ofhypocentral location and moment tensor inversion suggest both clusters correspond to thrust failureat or close to the slab interface. Beside these similarities, the temporal evolution of the clusters revealimportant differences suggesting a different origins: at the Navidad cluster the seismicity occurs inform of several short duration seismic swarms episodes, which we interpret as the result of transientprocesses affecting the slab interface, while at the Vichuquén cluster, seismicity is characterized bya sustained occurrence of repeated events over the considered time period, which we explain by alocalized topographic or material anomaly at the slab interface. The analysis of these two seismicclusters for a period of 18 years allow to identify their presence well before the preparation phase ofthe 2010 Maule earthquake, which rupture terminated in this region, and to date. While the longterm observation of the seismicity anomalies suggest their physical origin, the occurrence of the largeMaule earthquake shows an important impact in modulating the temporal evolution of the clusterover years. In the 2008 year preceding the Maule earthquake, seismicity appear strongly reduced,revealing a quiescence period. After the Maule Earthquake, cluster seismicity is increased and slowlydecaying, but to the date it has not yet recovered the previous background rate.

Page No. 48

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 49

Poroelastic, hydraulic and acoustic responses of porous sandstone to iso-tropic pressure

Lei Wang wanglei@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Lei Wang1, Georg Dresen1,2, Erik Rybacki1, Audrey Bonnelye1, Marco Bohnhoff1,3

1GFZ Potsdam, 2University of Potsdam, 3Free University of Berlin

Evolution of physical properties of porous sandstone with pressure plays an important role in reservoirengineering projects associated with oil and gas exploration. Here we systematically examined thevariation in a complete set of poroelastic, hydraulic and acoustic properties of porous Bentheim sand-stone (dual-porosity material) as a function of pressure under dry, drained and undrained conditions.Specifically, experimentally determined drained bulk compressibility, undrained bulk compressibilityand Skempton’s coefficient are decreased dramatically until crack closing pressure, and afterwards,they tend to level off implying the different pore space shapes strongly govern poroelastic parameters.In addition, the storage coefficient and Biot’s coefficient derived from poroelasticity also display asimilar tendency with pressure. Indirect evaluation of pore compressibility from measured indepen-dently poroelastic parameters is found to be constant, lying between pore fluid compressibility androck matrix compressibility, beyond crack closure pressure, but it seems to be questionable at lowerpressure. In terms of hydraulic properties, the permeability of Bentheim sandstone is decreased si-gnificantly until crack closure pressure, followed by a slow decline at high pressure. Although crackporosity is negligible in dual-porosity Bentheim sandstone, it dominates the evolution of permeabilityby substantially changing the tortuosity of seepage network. Ultrasonic P and S-wave velocity bothsignificantly increase with pressure prior to crack closure pressure in dry and wet cases, and then theygrow slowly afterwards. In addition to the majority of acoustic emission (AE) activities located at endsides of samples due to end effects, the rest of AEs are randomly distributed within the samples athigh pressure caused by energy release from stress concentration at grain-grain contact suggesting nolocalization of deformation occurs. Moreover, most AE source type is dominated by collapse eventsbased on analysis of first motion polarities. Finally, the effective medium theory (Mori-Tanaka sche-me) and squirt-flow model are deployed to model the pressure-dependent mechanical properties ofdry and water-saturated samples considering the different roles of cracks and pores.

Page No. 49

Poster Stand No 50 A0 posters: Poster Session 2: 16:30 – 17:30

Alpine headwall erosion rates based on 10Be concentrations in supraglacialdebris cover

Katharina Wetterauer katharina.wetterauer@gfz-potsdam.de3.3 - Earth Surface Geochemistry

Katharina Wetterauer1; Dirk Scherler1,2 ; Leif S. Anderson1

1GFZ German Research Centre for Geosciences, Potsdam, Germany; 2Freie Universität Berlin, Berlin,Germany

Debris-covered glaciers are fed from steep bedrock hillslopes (headwalls) that tower above the ice.Rockfalls and rock avalanches erode these headwalls and mobilize fractured bedrock, which is subse-quently deposited on the ice surface along the sides of valley glaciers and transported down valley onand in the ice. Debris tends to be older down glacier and, for typical Alpine glaciers, single depositsmay persist on the glacier surface for hundreds to a few thousand years. Where glaciers join, marginaldebris merges to form medial moraines. Once the debris layer is thicker than a few centimeters, itsinsulating effect reduces ice melting. According to recent observations, climate warming leads to head-wall destabilization and an increase in erosion rates (e.g., by changes in the frost-cracking intensityand permafrost degradation). An increased delivery of debris would thicken the glacial debris coverand influence surface melt rates. Consequently, the response of debris-covered glaciers to climatechange is likely also related to the response of these headwalls to climate change. In this context, myproject aims to quantify headwall erosion rates by measuring cosmogenic nuclide concentrations insupraglacial debris cover of glaciers in the European Alps. I will test if samples collected along medialmoraines allow us to recover changes in headwall erosion rates through time. We will then test ifchanges in headwall erosion rate also correlate with climate changes. During the first field campaign(September/ October 2018) we collected 38 debris samples along profiles from a total of four medialmoraines on two valley glaciers in the Swiss Alps, both nourished by a well-definable catchment areaof known lithology. Currently, I am separating and purifying quartz minerals from these samples, whichare required for the 10Be concentration measurements. In the long run we further intend to extendthe data set by sampling different glaciers in order to examine headwall erosion rates as a functionof elevation and, hence, temperature within various glacial landscapes across the European Alps.

Page No. 50

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 51

Radio magnetotelluric survey of the Quaternary Neualbenreuth maar in theWestern Bohemian Massif (Germany)

Gregor Willkommen willkomm@gfz-potsdam.de2.7 - Near-Surface Geophysics

Gregor Willkommen1,2, Paula Rulff3, Ute Weckmann1,2

1GFZ Potsdam,2Universität Potsdam, 3Uppsala University

Only within the last few years, a Quaternary maar was discovered in the vicinity of Neualbenreuth(NE – Bavaria, Germany), which is related to the development of the Eger Rift system in the CzechRepublic. It is one magmatic structure along the Tachov Fault Zone among the known scoria conesKomorní hůrka and Železná hůrka and the Quaternary Mýtina Maar, which was discovered a decadeago. An exploratory drilling project (NAR 2015) in the centre of the Neualbenreuth maar recoveredits post-volcanic fill, which is a succession of mostly laminated sediments under a 15m debris layer(Rohrmüller et al, 2017). These sediments are surrounded by crystalline bedrock with significantlyhigher electrical resistivity. While a refractions seismic survey in 2013 and geo-electric resistivitytomography (ERT) surveys in 2012 and 2016 revealed significant geophysical anomalies related withthe maar, it does not show any geomagnetic imprint. Compared with ERT, our Radiomagnetotelluricmeasurements (RMT) are more sensitive to conductors and done with an areal coverage allow for a3D inversion and interpretation. These measurements together with our RMT experiment are part ofan ICDP drilling campaign (PIER-ICDP) into geodynamic key sites within the Eger Rift to shed lighton the tectonic structure and related geodynamic processes. In April 2018, we recorded RMT data ina frequency range of (1MHz – 1kHz) along different profiles across the maar. For this purpose, weused the EnviroMTTM instrument from Uppsala University and the MK5-SM25 instrument from theUniversity of Cologne. Here, we will present results of a 2D inversion and a comparison with othergeophysical findings and borehole information.

Page No. 51

Poster Stand No 52 A0 posters: Poster Session 2: 16:30 – 17:30

Age and geomorphological controls on geo-bio successions in a sub-Arcticglacial forefield.

Robin Wojcik robin.wojcik@gfz-potsdam.de3.5 - Interface Geochemistry

Robin Wojcik1,2, Johanna Donhauser3, Beat Frey3, Anja M. Schleicher4, Liane G. Benning1,2

1GFZ - German Research Centre for Geoscience, Interface Geochemistry, Potsdam, Germany, 2FreeUniversity of Berlin, Geochemistry, Berlin, Germany, 3WSL Institute for Snow and Avalanche ResearchSLF, Forest Soils and Biogeochemistry Rhizosphere Processes, Birmensdorf, Switzerland, 4GFZ - Ger-man Research Centre for Geosciences, Inorganic and Isotope Geochemistry, Potsdam, Germany

Recently deglaciated areas are unique environments to study the initial development of soils throughthe alteration of exposed rocks due to weathering and microbial processes. Carbon (C) and nitrogen(N) contents as well as soil pH and soil elemental compositions are thought to be important controlsof variations in microbial communities in the early stages of soil ecosystem development. However,the functional linkages between C and N contents, soil composition and microbial community struc-tures remain poorly understood. To address this gap, we studied the correlations between weatheringprogression, C and N distributions and microbial community structures along a well-dated, 113 yearschronosequence in the glacier forefield of the sub-Arctic Fláajökull in south-eastern Iceland. Besidesterrain-age since deglaciation, post-deglaciation hydrological and / or slope-related geomorphologicaldisturbances have often been reported to exert a strong influence on patterns of soil developmentsuccession in glacial forefields in previous studies. Yet, the relative effect of these two parameterson soil development patterns in glacier forefield has not been quantitatively compared previously.To address this gap, we quantified the relative effects that geomorphological disturbances have onsoil development along a shorter transect across a flow channel in the forefield. Along the chronose-quence, we documented a decrease in pH, and soil grain size, accompanied by an in crease in clayfraction, soil organic carbon and nitrogen contents. We also observed a progression of weatheringalong the chronosequence via the relative depletion in silica contents as well as olivine. Additionally,we observed an increasing relative abundance in iron oxides and chlorites as well as an increasingabundance of trace elements (e.g., Cr, Ni and Zn) and a decreasing relative abundance of Sr. Ourresult showed a concurrent increasing abundance and diversity in the microbial community structuresalong the chronosequence. Multivariate analyses indicate strong correlations between the microbialcommunity structure and the main geochemical and physical soil characteristics. Our results showclear correlations between changing geomorphological disturbance levels and physical and chemicalsoil properties. The changes include variations in soil water contents, soil bulk density and soil grainsize distribution, elemental and mineralogical patterns, C and N contents as well as bacterial andfungal community abundance and diversity. Overall, our complementary and interdisciplinary datasetallowed us to develop a generic framework for how co-succession of microbial and geochemical chan-ges lead to soil development in a sub-Arctic glacial forefield. In this contribution, we also discuss towhat extent soil development along our chronosequence can be explained as the result of both terrainage since deglaciation and post-deglaciation geomorphological disturbances.

Page No. 52

A0 posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 53

Unravelling the role of lithofacies in controlling organic matter compositionin unconventional systems using FT-ICR-MS

Huiwen Yue Hyue@gfz-potsdam.de3.2 - Organic Geochemistry

Huiwen Yue, Stefanie Poetz, Yuanjia Han, Brian Horsfield, Andrea Vieth-HillebrandGFZ German Research Centre for Geosciences, Potsdam, Germany

Inorganic components, e.g. mineralogical composition, could play an important role in evolution oforganic matter (Murgich and Jesús Rodríguez, 1998). Jones et al. (1994) emphasized similarities inpetroleum generation for shale and carbonate source rocks but stressed possible differences in migra-tion. Carbonate source rocks tend to be more brittle, heterogeneous and tighter than clay rich sourcerocks, which makes them more prone to fracture and emit hydrocarbons more effectively. As definedby Jarvie (2012), unconventional resource systems include not only organic rich rocks which can gene-rate and store petroleum itself but also juxtaposed organic lean intervals where generated petroleumcan migrate into. Those juxtaposed organic lean units also have different lithofacies than the organicrich units. To elucidate the controls that different lithofacies may have on the composition of organicmatter in unconventional systems, we investigated samples from three different locations includingcarbonate-rich Niobrara Formation, biogenic quartz-rich Barnett Shale and clay-rich Posidonia Shale.All samples are of similar kerogen type (type II) and thermal maturity (0.88-1.02% Rc). For NiobraraFormation and Barnett Shale, samples were chosen from both, organic rich units and juxtaposed morecarbonate or quartz rich units. Thus, lithofacies effects on organic matter within and between diffe-rent unconventional systems are evaluated using (+)-APPI FT-ICR-MS with focus on retention andmigration processes. Differences in compound class distribution between those three sample sets canbe observed. Posidonia and Barnett Shale have higher (OxNy+Ny+Ox)/hydrocarbons, N2/N1 andN2O1/N1O1 ratios. More polar compounds and compounds containing two nitrogen atoms are retai-ned by Posidonia and Barnett Shale. This could indicate that clay and biogenic quartz have a higherretention potential. Within Niobrara and Barnett Shale, samples from organic rich units have higher(OxNy+Ny)/Ox, N2/N1 and N2O1/N1O1 ratios. OxNy and Ny compounds might be preferentially re-tained in the source in comparison to Ox compounds, and compounds containing two nitrogen atomsare better retained than compounds containing one nitrogen atom. High variability in (OxNy+Ny)/Oxvalues can be found between Barnett source and reservoir samples, while this variability is small withinNiobrara sample set (Figure1). This could be due to more efficient secondary migration in carbonaterich Niobrara samples. Within Niobrara Formation and Barnett Shale, samples from organic rich unitshave higher contribution from compounds with high DBE values and compounds in low carbon num-ber range within a specific DBE class, especially in N1O1 compound class. High DBE values indicatehigh aromaticity and increased molecular size of compounds. Compounds in low carbon number rangerepresent compounds with low alkylation grade and higher polarity in specific species. This fits toan observation of Mahlstedt et al (2016) that compounds with higher aromaticity and lower level ofalkylation are preferentially retained. Higher contributions of N1O1 compounds with high DBE values(DBE>9 N1O1 compounds) in Barnett and Posidonia Shale also argue for their increased retentionpotential compared to the Niobrara formation. This first insight into the (+)-APPI FT-ICR-MS dataindicates their high potential to elucidate controlling effects of lithofacies on petroleum retentionand migration in unconventional systems. References Jones, R. W. 1984. AAPG Studies in Geology18, pp.163-180. Jarvie, D.M., 2012. AAPG Memoir, 97, pp.69–87. Murgich, J., Rodríguez M, J.,Izquierdo, A., Carbognani, L., & Rogel, E., 1998. Energy & fuels, 12(2), pp.339-343. Mahlstedt, N.,Horsfield, B., Wilkes, H. and Poetz, S., 2016. Energy & Fuels, 30(8), pp.6290-6305

Page No. 53

Poster Stand No 54 A0 posters: Poster Session 2: 16:30 – 17:30

A new sediment core from Lake Lago Grande di Monticchio extending backto ca. 29,000 BP: preliminary results

Xueru Zhao amyzhao@gfz-potsdam.de4.3 - Climate Dynamics and Landscape Evolution

Xueru Zhao1, Markus Schwab1, Rik Tjallingii1, Sabine Wulf2, James Collins3, Dirk Sachse3,and Achim Brauer11GFZ German Research Centre for Geosciences, Section ’Climate Dynamics and Landscape Evolution’,Potsdam, Germany, 2Institute for Geosciences, Department of Geography, University of Portsmouth,Portsmouth, UK, 3GFZ German Research Centre for Geosciences, Section ’Geomorphology’, Potsdam,Germany

The high-resolution Monticchio (MON) sediment record has been demonstrated to be a key archi-ve for reconstructing climate and environmental changes in the central Mediterranean for the lastglacial-interglacial cycle (e.g., Allen et al., 1999; Brauer et al., 2007; Martin Puertas et al., 2014).New sediment cores have been retrieved in April 2016 to investigate particularly the transition fromthe Last Glacial Maximum into the Holocene with a new high-resolution methodological approach.Accordingly, 5 new parallel sediment cores were obtained forming a 12.5m composite profile cove-ring the last ca. 29,000 yrs. The preliminary age-depth model of the new sediment profile is basedon tephrochronology and implements 7 published dates of well-known Italian tephras. These inclu-de ages of the Mercato (TM-6b; 8,530±100 cal yrs BP), Verdoline (TM-12; 19,226±104 cal yrs BP)and Pomici di Base (TM-13; 22,081±173 cal yrs BP) eruptions of Vesuvius, as well as the Soccavo(11,700±150 cal yrs BP), Pomici Principali (TM-7b; 12,037±122 cal yrs BP), Neapolitan Yellow Tuff(TM-8; 14,194±172 cal yrs BP) and Y-3 eruptions (TM-15; 29,059±178 cal yrs BP) of the PhlegraeanFields. Additional radiocarbon dating and varve counting on the new cores is currently in progressfor establishing a more detailed chronology. Here we present first high-resolution -XRF element scan-ner data combined with new micro-facies data covering the interval between the Pomici di Base(22081±173 cal yrs BP) and Mercato (8530±100 cal yrs BP) tephra layers. Tephra layers and rewor-ked volcanic ash are well reflected by peaks in potassium. Detrital sediments indicated by Titanium(Ti) gradually decrease from the Last Glacial Maximum until the lateglacial interstadial with relative-ly low values and only minor fluctuations. The Younger Dryas is reflected by recurrence of detritalsediments without reaching pleniglacial values. Si/Ti ratios indicate relative variations of diatom pro-ductivity in the lake and show only a weak increase during the late glacial interstadial and subsequentdecline during the Younger Dryas before the main increase in the early Holocene. Further work inclu-ding biomarker stable isotopes will particularly focus on the Younger Dryas climate change and thecomparison of MON data with high-resolution lake records in western and central Europe. Judy R. M,Allen. et al. Rapid environmental changes in southern Europe during the last glacial period. Nature400, 740-743 (1999). Brauer, A. et al. Evidence for last interglacial chronology and environmentalchange from Southern Europe. Proceedings of the National Academy of Sciences of the United Statesof America. PNAS 104, (2), 450-455 (2007). Martin-Puertas, C. et al. Annual proxy data from LagoGrande di Monticchio (southern Italy) between 76 and 112 ka: new chronological constraints andinsights on abrupt climatic oscillations. Clim. Past 10, 2099-2114 (2014).

Page No. 54

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 55

Receiver Function Imaging of the Mantle Transition Zone beneath CentralMyanmar

Yiming Bai yiming@gfz-potsdam.de2.4 - Seismology

Yiming Bai1,2, Xiaohui Yuan2, Yumei He1,3, Myo Thant4, Kyaing Sein5, Shun Yang1, Yins-huang Ai1,3

1Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China, 2Deutsches Geo-ForschungsZentrum GFZ, Potsdam, Germany, 3CAS Center for Excellence in Tibetan Plateau EarthScience, Beijing, China, 4Department of Geology, Yangon University, Yangon, Myanmar, 5MyanmarGeosciences Society, Yangon, Myanmar

Myanmar is located at the eastern margin of the on-going Indo-Eurasian collision system which createdthe Tibetan plateau and Himalayas. While regional seismic tomography indicated that the Indianplate is obliquely subducting eastward beneath the Burma microplate, these studies did not providesufficient resolution on whether the slab has descended deeply into the mantle transition zone (MTZ),largely due to the lack of local seismological observations in Myanmar. Here, we apply P receiverfunctions (RFs) to detect the MTZ discontinuities with the seismic data collected from the China-Myanmar Geophysical Survey in the Myanmar Orogen (CMGSMO) project. The topographies of the410- and 660-km discontinuities could provide important constraints on the depth extent of the slabfor they are sensitive to the temperature variation near the MTZ. 164 earthquakes with magnitudesgreater than 5.8 and at epicentral range of 30 ◦ – 90 ◦ were selected for the calculation of RFs.A depth section along ∼22 ◦ N was constructed by a common conversion point (CCP) stack approach.From 95 ◦ to 97 ◦ E in this section, the 410- and 660-km discontinuities are ∼18 km and ∼13 kmshallower than the global averages, respectively. Furthermore, we slant-stacked receiver functionsat each stacking bin along the section as a function of time and slowness. This technique helpsclean up the multiples from shallower depths atop of the 410-km discontinuity and reveal a negativesignal at ∼370 km, suggesting a shear-wave velocity drop at this depth. The uplift of the 410-kmdiscontinuity and thicken of the MTZ appeared on our CCP stacked image might, to some extent,attribute to the eastward subducting Indian plate. This preliminary result is coherent well with a newbody-wave tomography model derived from the same network. Further investigations would revealdetailed topographies of the MTZ discontinuities and therefore better constrain the dynamic processof the subducting Indian plate. This study is supported by the National Natural Science Foundationof China (grants 41490612, 41474040).

Page No. 55

Poster Stand No 56 EGU posters: Poster Session 2: 16:30 – 17:30

Mg stable isotopes cycling in the Black Forest at different time scales

Di Cai dcai@gfz-potsdam.de3.3 - Earth Surface Geochemistry

Di Cai, David Uhlig, Michael Henehan, Friedhelm von BlanckenburgGFZ potsdam

Magnesium (Mg) is the eighth most abundant element in the continental crust and also an essentialbiological nutrient, and thus it plays an important role in biogeochemical cycles. Here, Mg isoto-pe compositions are reported for paragneiss bedrock, soils, vegetation, seasonal stream water andinterflow solutions collected from the Black Forest. Bulk soils (δ26Mg = −0.01%�) are isotopical-ly lighter than the bedrock (δ26Mg = −0.21%�) by 0.2%�, which is induced by either selectiveleaching or secondary precipitation. Vegetation (δ26Mg = −0.87%� to −0.27%�) is also isotopi-cally lighter than the stream water, suggesting it takes heavy Mg from growth media. Mg isotopecompositions of stream water (δ26Mg = −0.68 ± 0.11%�) and interflow (from 0.1m below ground,δ26Mg = −0.80 ± 0.06%�) are relatively constant throughout a hydrological year. We suggest thatMg isotope composition of water draining out of the critical zone might be largely determined at veryshallow depth of the critical zone. Biological cycling within the plant/surface-soil component ratherthan lower soil profile may control the input of cations to the stream water in our case. This studydemonstrates that Mg isotopes provide a valuable tool for investigating nutritive elements cycling inthe critical zone.

Page No. 56

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 57

Simulations of the inner magnetospheric energetic electrons using the IMPTAM-VERB coupled model

Angelica Maria Castillo Tibocha angelica@gfz-potsdam.de2.8 - Magnetospheric Physics

Angelica M. Castillo1,3, Yuri Y. Shprits1,2,3, Natalia Ganushkina4,5, Alexander Drozdov2, Ni-kita Aseev1,2,3, Dedong Wang1, Stepan Dubyagin5

1GFZ German Research Centre For Geosciences, Potsdam, Germany; 2Department of Earth, Plane-tary and Space Sciences, University of California, Los Angeles, CA, USA; 3Institute of Physics andAstronomy, University of Potsdam, Potsdam, Germany; 4University of Michigan, Ann Arbor, MI, USA;5Finnish Meteorological Institute, Helsinki, Finland

In this study, we present initial results of the coupling between the Inner Magnetospheric ParticleTransport and Acceleration Model (IMPTAM) and the Versatile Electron Radiation Belt (VERB-3D) code. IMPTAM traces electrons of 10− 100 keV energies from the plasma sheet (L = 9 Re) toinner L-shell regions. The flux evolution modeled by IMPTAM is used at the low energy and outerL* computational boundaries of the VERB code to perform radiation belt simulations of energeticelectrons. The model was tested on the March 17th, 2013 storm, for a six-day period. Four differentsimulations were performed and their results compared to satellites observations from Van Allenprobes and GOES. The coupled IMPTAM-VERB model reproduces evolution and storm-time featuresof electron fluxes throughout the studied storm in remarkable agreement with the satellite data.Including dynamics of the low energy population at L* = 6.6 increases fluxes closer to the heartof the belt and has a strong impact in the VERB simulations at all energies. However, inclusion ofmagnetopause losses leads to drastic flux decreases even below L* = 3. The dynamics of low energyelectrons (max. 10s of keV) do not affect electron fluxes at energies ≥ 900 keV. Since the IMPTAM-VERB coupled model is only driven by solar wind parameters and the Dst and Kp indexes, it is suitableas a forecasting tool. In this study, we demonstrate that the estimation of electron dynamics withsatellite-data-independent models is possible and very accurate.

Page No. 57

Poster Stand No 58 EGU posters: Poster Session 2: 16:30 – 17:30

Assimilation of multisatellite data using a Kalman filter, a window for abetter understanding of the near-Earth environment

Juan Sebastian Cervantes Villa jscv@gfz-potsdam.de2.8 - Magnetospheric Physics

Juan Sebastian Cervantes Villa1,2, Yuri Shprits1,2,3, Adam Kellerman3, Alexander Drozdov3

1GFZ, German Research Centre for Geosciences, Potsdam, Germany, 2University of Potsdam, Pots-dam, Germany, 3University of California, Los Angeles, CA, USA

The dynamical evolution of the radiation belts has been a subject of extensive research since theirdiscovery in 1959. After decades of study, it is now known that they experience significant changes dueto acceleration, loss and transport of particles trapped in the Earth’s magnetic field. Since high-energyelectrons can potentially cause spacecraft anomalies and damage satellite hardware, understandingand predicting fluxes in the radiation belts is of great importance to satellite operators, engineers,and designers. Nevertheless, analysis of radiation belt observations presents major challenges. Satelliteobservations are often restricted to a limited range of L-shells, pitch angles, and energies. Additionally,observations at different L-shells are taken at different points along the spacecraft orbit and thereforeat different times. Moreover, particle fluxes vary on short time scales, and observations from a singlespacecraft do not allow for measuring the temporal variations on time scales shorter than the space-craft orbital period. Analysis is further complicated by the fact that measurements are contaminatedby errors, which are different for various instruments. As a consequence, to fill the spatiotemporal gapsand to understand the dynamics and dominant physical processes in the radiation belts as well as tocreate accurate models, observations should be combined with physics based dynamical models in anoptimal way. Numerical weather prediction faced similar problems to those mentioned in the 1970s. Amethodology, usually referred as data assimilation, in which observations are combined with models inorder to produce results close to the true values, was successfully applied. With the advent of space-borne observational data and the development of more sophisticated space-physics models, dynamicalprocesses in the Earth’s radiation belts can be analyzed and assessed using data assimilation methodsas well. In this study we implement a data assimilation tool using a split-operator sequential Kalmanfilter approach. Reanalysis of the electron radiation belt fluxes is obtained over the period October2012 to October 2015 by combining sparse observations from the Van Allen Probes spacecraft andthe Geostationary Operational Environmental Satellites 13 and 15 with the 3D Versatile ElectronRadiation Belt code. At first, radial profiles of electron fluxes are reconstructed, and the innovationvector is analyzed to show how the data is correcting for physical mechanisms absent in the model.Such processes (mixed pitch angle-energy diffusion, losses to the magnetopause, and scattering byElectromagnetic Ion Cyclotron waves) are then added in the reanalysis, and a validation against LANLGPS data is presented. Finally, major improvements with respect to the pure physics based model arediscussed. It is demonstrated that the 3D data assimilative code provides a comprehensive pictureof the radiation belts and is an important step toward performing reanalysis using observations fromcurrent and future missions.

Page No. 58

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 59

Local earthquake tomography of the southern Puna Plateau

Jing Chen jingchen@gfz-potsdam.de2.4 - Seismology

Jing Chen1,2, Sofia-Katerina Kufner2, Xiaohui Yuan2, Benjamin Heit2, Hao Wu1, DinghuiYang1, Suzanne M. Kay3

1Tsinghua University, Beijing, China, 2Deutsches GeoForschungaZentrum GFZ, Potsdam, Germany,3Cornell University, Ithaca, USA

The Puna Plateau is a part of the Andean Plateau, which has been formed by the subduction of theoceanic Nazca plate beneath the South American continental plate. The southern Puna Plateau isanomalous with respect of the rest of the Andean Plateau in having a distinct magmatic and structuralhistory. It has a large deficit in crustal shortening compared to its elevation and an underlying slab witha transitional dip between a steeper segment to the north and a flat slab to the south. Additionally, thecontinental lithosphere in the southern Puna Plateau is much thinner than the northern Puna Plateau.Mainly based on geochemical and geological observations, a model of lithospheric delamination wasproposed to explain these distinct features, which predicts melting in the crust and mantle lithosphere.Here we show new results from local earthquake tomography within this region, which we can useto test the delamination hypothesis as a working model for the subduction and orogenic processes.Our results are derived from seismic data recorded by a 74 station seismic network, which has beenoperated from 2007 to 2009 in Argentina and Chile, covering a major area of the southern PunaPlateau. We performed the seismic tomography using both P-wave and S-wave traveltimes from localearthquakes recorded by the seismic network and obtained 3D velocity models for P-wave velocityand Vp/Vs ratio. More than 1000 events and 30 thousand P and S first arrival picks are analyzed andweighted automatically during the inversion procedure based on the misfit between the calculatedand real travel time. We apply damped-least-squares full matrix inversion for 3-D velocity structurewhich is described as over 3000 grids. The tomography images show a low P-wave velocity anomaly inthe crust in the center of the study region, which coincides with the location of the Central VolcanicZone. In the southeastern part of the region beneath north Pampas, a high P-wave velocity blockin crust and uppermost mantle is observed, which can possibly be interpreted as the evidence of thedelaminated lithospheric block.

Page No. 59

Poster Stand No 60 EGU posters: Poster Session 2: 16:30 – 17:30

Assessing the temperature sensitivity of frost weathering and erosion inglacial landscapes

Donovan Dennis dennis@gfz-potsdam.de3.3 - Earth Surface Geochemistry

Donovan Dennis, Dirk Scherler, Hella Wittmann, Samuel NiedermannGFZ-Potsdam, Freie Universität Berlin

Ice-dependent weathering mechanisms operating at or below 0 ◦C are important contributors to thebreakdown of bedrock material in cold regions. These processes (e.g. segregation ice-wedging, freeze-thaw cracking, etc.) are sensitive to small changes in temperature, particularly those that bringthe bedrock above freezing. Though the nature of this temperature dependence has been discussedthoroughly in the theoretical and experimental literature, in-situ studies are limited. Unraveling theresponse of landscapes to changing climates is nonetheless important for understanding the controls(on both short and long timescales) of climate on erosion and related Earth surface processes. Assuch, in my project I seek to evaluate the temperature sensitivity of glacial landscapes and other coldregions where frost weathering is active. I plan to realize this assessment using a novel combinationof field observation, cosmogenic nuclide geochemistry, and numerical modeling. Following recentfieldwork in the European Alps, I am currently preparing ∼ 15 samples for cosmogenic nuclide (3Heand 10Be) analysis. These measurements will allow me to determine glacier headwall erosion (retreat)rates (10Be) as well as time-integrated bedrock paleotemperatures. Here, I present preliminary workon a 1D numerical model of thermal diffusion, erosion, and cosmogenic nuclide inventory in in-situbedrock which will later allow for the interpretation of 10Be- and 3He-derived erosion rates andpaleotemperatures. I am furthermore evaluating the magnitude of frost-cracking at near-grain-sizescales by assessing rock porosity and quantifying micro-crack abundances, and additionally presentthese early results here.

Page No. 60

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 61

Full-Waveform Inversion for Seismic Velocity and Moment Tensor Solutionsbeneath North Chile

Yajian Gao yjgao@gfz-potsdam.de2.4 - Seismology

Yajian Gao, Frederik Tilmann, Dirk-Philip van Herwaarden, and Andreas FichtnerGFZ Potsdam, ETH Zürich

We present a new seismic tomography model including radial anisotropy based on Multiscale FullSeismic Waveform Inversion for the crustal and upper-mantle structure beneath northern Chile, whichis a part of the Nazca-South America Plate boundary known for frequent megath- rust earthquakesand volcanos. The forward and adjoint simulation based on a 3D model are accomplished with Salvus,which is a suite of spectral-element method solver of the seismic wave equation and of its adjoint,working in 2D and 3D tetrahedral, hexahedral, quadrilateral and triangular meshes. We perform theinversion running on the Piz Daint, hosted by Swiss National Computing Centre and invert waveformsfrom 78 events which are carefully selected for good coverage of the study region and depth range,yielding in total 6854 event-station pairs, 74% of which have effective time windows for full-waveforminversion. In order to mitigate the risk of convergence towards local minima, we divide the wholeinversion procedures into three different time-period stages (40-80 s, 30-80 s and 20-80 s). The startingmodel is retrieved from the Collaborative Seismic Earth Model (Fichtner et al., 2018) and we proceedthe inversion from lower to higher periods. We take advantage of the adjoint methodology coupledwith precondi- tioned conjugate-gradient optimization scheme to update the seismic velocity model.Through full-waveform inversion, we effectively improve the resolution of the current model. The mostconspicuous feature is the strong radially anisotropy for S wave velocity: the Vsv and Vsh within thesubducted slab demonstrate an obvious different strength and shape. Meanwhile, in order to alleviatethe effect of inaccuracy of earthquake source parameters, in particular depth, on the seismic velocitymodel inversion and to update the moment tensor catalogue, we implementeded a seismic sourceinversion workflow based on Greens’ Functions calculated for 1-D and 3-D seismic velocity models.We take a consecutive way to update our Greens’ functions based on the updated Seismic velocitymodel from our adjoint inversion com- bined with the high-frequency analytic Greens’ functions basedon 1-D model for incorporating more body wave phases.

Page No. 61

Poster Stand No 62 EGU posters: Poster Session 2: 16:30 – 17:30

Does age matter? How hydrological flow paths change through the millennia

Anne Hartmann aha@gfz-potsdam.de4.4 - Hydrology

Anne Hartmann, Ekaterina Semenova, Markus Weiler, Theresa BlumeGFZ Potsdam

The presence or absence of preferential flow strongly controls water flow and transport in soils. Itis ubiquitous, but difficult to characterize and predict. This study addresses the occurrence and theevolution of preferential flow during the evolution of landscapes. We targeted a chronosequence ofglacial moraines in the Swiss Alps (Sustenpass) to investigate how water transport paths evolve alongwith the soil forming processes. Dye tracer irrigation experiments with Brilliant Blue solution (4 g/L)were conducted on four moraines of different ages (10000, 3000, 160, and 30 yr.). The irrigated bluedye infiltrates into the soil, while staining its flow paths during this process. At each moraine, threedye tracer experiments were conducted on plots of 1.5 x 1.0m. The three plots at each moraine werecharacterized by different vegetation complexities (low, medium, high). Each plot was further dividedinto three equal subplots for the application of three different irrigation amounts (20, 40, 60mm) withan average irrigation intensity of 20mm/h. The day after the experiment five vertical soil sectionswere excavated and the stained flow paths were photographed. A digital image analysis was used toderive average infiltration depths and flow path characteristics like volume and surface density of thedye patterns. Based on the volume density, the observed dye patterns were assigned to specific flowtype categories. The results show a significant change in type of preferential flow paths along thechronosequence of glacial moraines. The flow types change from a rather homogeneous gravity drivenmatrix flow in coarse material with high saturated conductivities and a sparse vegetation cover at theyoungest moraine to a heterogeneous infiltration pattern at the medium age moraines. Heterogeneousmatrix and finger flow are dominant at these middle age classes and also favored by a rather highhydraulic conductivity of the sandy soils. At the oldest moraine only macro pore flow via root canalswas observed in deeper parts of the soil, in combination with a very high water storage capacity of theorganic top layer and low hydraulic conductivity of the deeper soil. In general, we found an increasein water storage with increasing age of the moraines, based on our observations of the reduction ininfiltration depth as well as laboratory measurements of porosity. Preferential flow is, however, notonly caused by macropores, but especially for the medium age moraine seems more controlled by soilsurface characteristics (vegetation patches and micro-topography).

Page No. 62

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 63

Multi-criterial calibration of WGHM in the Ganges-Brahmaputra basin

H.M. Mehedi Hasan mhasan@gfz-potsdam.de4.4 - Hydrology

H.M. Mehedi Hasan1, Andreas Güntner1, and Fabrice Papa2

1GFZ-Potsdam, Hydrology, Potsdam, Germany, 2LEGOS, IRD/CNES/CNRS/UPS, Toulouse, France

The transboundary river basin Ganges-Brahmaputra (GB) of over 1.7 million km2 in size is homeof estimated over 600 million inhabitants, distributed between India, China, Nepal, Bangladesh andBhutan. Understanding hydrological dynamics in this region is of immense importance for watermanagement and supply. Global-scale hydrological models like the WaterGAP Global HydrologicalModel (WGHM) provide a means of analyzing hydrological processes and the water cycle dynamicsin such a complex river basin towards water availability assessment at a regional scale. However, hugeuncertainty of large-scale hydrological models hinders their reliable application. A Pareto-based opti-mization concept for more than one calibration variable can be used to reduce the model uncertaintyand equifinality through model calibration prior to any model application. Here, we calibrated the12 and 11 most sensitive parameters of WGHM for the Ganges and Brahmaputra, respectively. Thesensitive parameters were identified using Morris’s Elementary Effect Test (EET) method for each ba-sin. The model was calibrated against four observations – in situ river discharge (Q), satellite-derivedevapotranspiration (ET), surface water storage variations (SWSV) from multi-satellite observationsand GRACE-based total storage variations (TWSV). As calibration objective for each observable theKling-Gupta Efficiency of basin-scale monthly averages was used. The Pareto frontier of the objec-tives was approximated using the Multi-Objective Evolutionary Algorithm Borg-MOEA. Borg-MOEAperformed well in estimating Pareto optimal model parameters as well as identifying the trade-offsamong objectives. Good model performance for the calibrated variables usually was at the expenseof simulation performance for the other variables that were not included in calibration. The largesttrade-off was observed between river discharge (Q) and surface water storage variations (SWSV)which suggests that constraining the model only with discharge observations results in inappropria-te simulations of SWSV. We observed poor performance of WGHM to generate accurate SWS infast responding basin like Ganges especially during heavy rainfall in monsoon. In general, however,any additional observation considered during calibration helped to better represent the hydrologicaldynamics, with good performance for all considered performance criteria.

Page No. 63

Poster Stand No 64 EGU posters: Poster Session 2: 16:30 – 17:30

Using multi-layer complex networks to understand changes in flood occur-rence

Matthias Kemter kemter@gfz-potsdam.de4.4 - Hydrology

Matthias KemterGFZ Potsdam, Universität Potsdam, PIK Potsdam

Like many naturally occurring phenomena, floods are an outcome of multiple processes that interactin intricate ways. Complex networks have proven to be a useful tool to represent and analyze suchinteractions. By combining different hydrological and climatological parameters (e.g. discharge, preci-pitation, catchment wetness) into multi-layer complex networks, I aim to improve our understandingof their role in flood event generation across Europe. The layers of the networks represent the dif-ferent parameters, while the nodes stand for measurement points like river gauges or satellite datapixel. Links between nodes are established where their respective time series are particularly similar,which I determine by event synchronization. I create several of these networks for moving temporalwindows of 10 years. This allows an investigation of changes of the network metrics – and therebythe underlying processes – between 1950 and 2010.

Page No. 64

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 65

Modeling the effects of regional groundwater flow on deep temperatures inHesse (Germany)

Nora Koltzer koltzer@gfz-potsdam.de4.5 - Basin Modelling

Nora Koltzer1,2, Magdalena Scheck-Wenderoth1,2, Judith Bott1, Mauro Cacace1, KristianBär3, Ingo Sass31Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, 2RWTH Aachen, 3TechnischeUniversität Darmstadt

A successful utilization of deep geothermal resources requires to make accurate predictions about thereservoir temperature distribution as well as an in depth knowledge of the hydraulic processes exertinga direct influence on the subsurface temperature distribution and therefore on the productivity ofgeothermal reservoirs. The aim of this study is to investigate and quantify the influence that regionalthermo-hydraulic processes exert on the geothermal configuration of potential reservoirs in the Germanfederal state Hesse. Specifically, we address the question of how the regional thermal and hydraulicconfiguration influences the local reservoir conditions and whether it is possible to improve subsurfacepredictions iteratively by relying on 3D numerical modeling techniques. Therefore, a 3D structuralmodel of Hesse is used as a basis for coupled 3D thermo hydraulic simulations of the deep fluid and heattransport. To uncover the effects of process coupling, a stepwise workflow is followed. We first simulatethe thermal and hydraulic field under steady-state conditions by means of two different uncoupledsimulations and then analyze the results of the coupled thermo-hydraulic steady-state simulations.In a last effort, we investigate the influence of fluid viscosity and density varying with temperatureand pressure in transient coupled simulations. As a result of our numerical simulations, Hesse can bedifferentiated into sub-areas differing in terms of the dominating heat transport processes. In a finalattempt to quantify the robustness and reliability of the modeling results, we carry out an analysisof the modelling outcomes by comparing them to available subsurface temperature data. Modelledtemperatures show different levels of fit with locally measured well temperatures. These differencesin model fit indicate the need for either structurally refined models and/or iterative adaptions withinrealistic ranges of the hydraulic and thermal properties. Structural refinements can often only behandled with smaller-scale models, which will, in turn, benefit from the boundary conditions andimproved process understanding as derived from the regional modelling approach presented here.

Page No. 65

Poster Stand No 66 EGU posters: Poster Session 2: 16:30 – 17:30

The role of spatial cross-correlation structures of ground motion fields forseismic risk assessment of spatially distributed assets and infrastructurenetworks

Henning Lilienkamp lilienka@gfz-potsdam.de2.6 - Seismic Hazard and Risk Dynamics

Henning Lilienkamp, Fabrice Cotton, Giuseppe Caire, Graeme WeatherillGFZ Potsdam, University of Potsdam

The treatment of spatially distributed infrastructure networks is currently one of the most eminentdevelopments in the research field of seismic hazard analysis and risk assessment. As a first step, aswould be necessary for the risk assessment of spatially distributed building portfolios, it is essentialto gain a comprehensive understanding for the spatial cross-correlation structure of ground motionintensity measures. Various models describing the spatial correlation and spectral cross-correlation ofground motion fields have been proposed in the last two decades and their effects on loss estimateshave been evaluated for a broad range of spatially distributed assets. As a general result, treatingthe ground motion at a single site and spectral period that is statistically independent of the groundmotion at all other sites and periods leads to a systematic overestimate of small frequent losses and,perhaps more critically, an underestimate of large rare losses. Whilst the incorporation of spatial cross-correlation structures leads to improved risk assessment for spatially distributed building portfolios,it is absolutely critical in order to estimate the connectivity and performance state of infrastructurenetworks, since their individual elements cannot be treated independently from each other. In orderto evaluate the progress in this research field in detail, we aim at a selection and comparison of thecurrently available correlation models. Furthermore, the effect of the epistemic uncertainty arisingfrom the diversity of available correlation models on the calculation of loss exceedance curves shall beinvestigated. This way we expect to provide a fundamental element of the groundwork on which furtherresearch in the direction of seismic risk assessment for infrastructure networks will be carried out. Wehope to provide an easily accessible overview on this research aspect that facilitates the entrance intothis research field for us and other researchers who consider participating in the development of aframework for seismic risk assessment of spatially distributed infrastructure networks.

Page No. 66

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 67

Mapping the Moho with ambient noise autocorrelations across a N-S profilecrossing the Bohemian Massif and Eastern Alps (EASI)

Stefan Mroczek mroczek@gfz-potsdam.de2.4 - Seismology

Stefan Mroczek and Frederik TilmannGFZ Potsdam, Freie Universität Berlin

In the field of seismic interferometry, cross-correlations are used to extract Green’s function fromambient noise data. By applying a single station variation of the method, using auto-correlations, weare able to retrieve zero-offset body wave reflections for vertical, and under favourable conditions,horizontal components. At a test station (HYB - Hyderabad, India) we determine the Moho P-wave and S-wave reflection times and find agreement with receiver function results. Applying thismethod to the EASI (Eastern Alpine Seismic Investigation) profile across the eastern Alps, we areable to identify the primary Moho reflection and estimate the crustal average vP /vS ratio for theBohemian Massif. In the Alpine section of the profile the Moho becomes more difficult to imageand our interpretation diverges from Moho depths based on receiver functions and autocorrelation ofteleseismic earthquake coda. Conventional receiver functions contain ambiguity between vP , vS, anddepth. P- and S-wave reflection times constrained with autocorrelations can be used in combinationwith receiver function multiples to determine interface depths, vP and vS independently. The phaseweighted autocorrelation stacks become stable after approximately two months of data which benefitsstudies with shorter deployment times.

Page No. 67

Poster Stand No 68 EGU posters: Poster Session 2: 16:30 – 17:30

High temperature shear zone formation around material heterogeneities:effect of boundary conditions during nucleation and transient evolution

Livia Nardini nardini@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Livia Nardini, Erik Rybacki, Maximilian Döhmann, Sascha Brune, Luiz Morales, Georg Dre-senGFZ Potsdam, University of Potsdam, ETH Zürich

Rock deformation at depths in the Earth’s crust is often localized in high temperature shear zones,which occur in the field at different scales and in a variety of lithologies. The presence of materialheterogeneities is known to trigger shear zone development, but the mechanisms controlling initiationand evolution of localization are not fully understood, as is the effect of boundary conditions. Toinvestigate the effect of the loading configuration on shear zone nucleation, we performed torsionexperiments under constant twist rate (CTR) and constant torque (CT) conditions in a Paterson-type deformation apparatus. The sample assemblage consisted of copper-jacketed Carrara marblehollow cylinders containing a thin plate of Solnhofen limestone oriented perpendicular to the cylinder’slongitudinal axis. Under experimental conditions (900 ◦C temperature, 400MPa confining pressure),samples were plastically deformed and the limestone, being about 9 times weaker than the marble,acts as a weak inclusion in a strong matrix. CTR experiments were performed at maximum bulk strainrates of ≈ 2 · 10−4s−1, yielding peak shear stresses of 19 – 20MPa. CT tests were conducted at shearstresses between 18 and 20MPa, resulting in bulk shear strain rates of 1− 4 · 10−4s−1. Experimentswere terminated at maximum bulk shear strains of ≈ 0.3 and 1.0. Strain was localized within the hostCarrara marble in front of the inclusion in an area (process zone) where grain size reduction is intense.The local shear strain is up to 10 times higher than the applied bulk strain at the inclusion tip, rapidlydropping to 2 times higher at larger distance from the inclusion. At both bulk strains, the evolution ofmicrostructural and textural parameters is independent of loading conditions. Our results suggest thatmaterial heterogeneities induce stress concentration halos resulting in strain partitioning into localizedshear bands. Progressive localization is associated with strain weakening accommodated by dynamicrecrystallization and the development of a crystallographic preferred orientation of sheared grains.Loading conditions do not significantly affect localization during nucleation and transient (bulk shearstrain ≈ 1) evolution stages. 2D Cartesian numerical modeling benchmarked to our experimentalresults successfully reproduces the qualitative aspects of strain localization and bulk stress-straintransients. Locally, the presence of coexisting brittle deformation is observed regardless of loadingconditions. The interaction between brittle and ductile deformation features is currently investigatedby means of triaxial experiments at low confining pressures.

Page No. 68

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 69

Numerically modelling the controls of crustal strength on microplate for-mation: application to the São Paulo Plateau microplate

Derek Neuharth djneuh@gfz-potsdam.de2.5 - Geodynamical Modelling

Derek Neuharth1, Sascha Brune1,2, Anne Glerum1, Christian Heine3

1GFZ German Research Centre for Geosciences, Potsdam, Germany. 2Institute of Geosciences, Univer-sity of Potsdam, Potsdam-Golm, Germany. 3Specialist Geosciences, PTD/E/F, Shell Global SolutionsInternational B.V., Rijswijk, NL

The São Paulo Plateau is a submarine bathymetric high located in the Santos Basin off the coastof Brazil. Observations from potential field, seismic refraction and -reflection data indicate thatthe plateau is likely underlain by thinned continental crust. Crustal thickness, sedimentary infill andfault patterns show characteristics of a microplate, which formed in-between the African and SouthAmerican plates when the Central and Southern rift segments of the South Atlantic emerged with anoffset of several hundred kilometers. The underlying reason for the formation and kinematic evolutionof the São Paulo Plateau microplate, as well as the amount of rotation and internal deformation, arenot well constrained. In this study, we test the effect of crustal strength on microplate formation andevolution in a two-branch rift system. We use the Advanced Solver for Problems in Earth’s ConvecTion(ASPECT) code to numerically simulate orthogonal rifting with nonlinear visco-plastic rheology. Thesetup consists of a 3-D box model with dimensions of 600 x 500 x 160 km (X, Y, and Z) that is extendedfor 400 km over 50My. Extension is prescribed as a constant or time dependent outward velocity at theX-normal boundaries, while the Y-normal boundaries are free-slip, with volumetrically compensatinginflow prescribed on the bottom and a free surface at the top. The two rift segments are initialized by125 km long lithosphere-asthenosphere boundary perturbations of 17 km amplitude at the front andback boundaries that are located 200 km apart in the X-direction. Lithosphere and crustal thicknessesare constant at 120 km and 35 km respectively, and the crustal strength variations are determined bythe ratio of the thickness of upper to lower crust. Initial results indicate that a setup with strong crustevolves in two possible ways. In the first case, the fault segments grow until connected by a transformfault. In the second case, one fault stretches across the domain while the other segment dies out.A setup with weaker crust results in an overlap of the segments and a subsequent topographic highforming between them. The rift segments are connected either by a transform fault that forms andtransects the topographic high, or by a rotating microplate that eventually connects to one of theplates by a rift jump. In the last case, the model is consistent with observations from the SantosBasin and allows us to constrain the spatiotemporal evolution of the microplate and the dynamics ofthe eastward rift jump that ultimately transferred the microplate to the South American plate.

Page No. 69

Poster Stand No 70 EGU posters: Poster Session 2: 16:30 – 17:30

Statistical study of Medium-Scale Traveling Ionospheric Disturbances (MS-TIDs) characteristics with GPS network over at North African region.

Temitope Seun Oluwadare oluwa@gfz-potsdam.de1.1 - Space Geodetic Techniques

Oluwadare Temitope Seun1,2, Chinh Nguyen Thai1,2, Oladipo Emmanuel Abe3, Cesar E.Valladares4, Mahdi Alizade5, Harald Schuh1,2

1German Research Centre for Geosciences (GFZ), Telegrafenberg, section 1.1 - Space Geodetic Tech-niques, Potsdam,Germany, 2Institut für Geodäsie und Geoinformationstechnik, Technische UniversitätBerlin(TU Berlin), Juni 135, 10623 Berlin, Germany, 3Department of Physics, Federal University Oye-Ekiti, Ekiti State, Nigeria, Nigeria, 4W. B. Hanson Center for Space Sciences, University of Texas atDallas, Richardson, TX, USA, 5Faculty of Geodesy and Geomatics Engineering, K. N. Toosi, Univer-sity of Technology, Tehran, Iran

One of the frequent ionospheric phenomena causing irregularities in the F region is the TravelingIonospheric Disturbances (TID). Medium scale TIDs (MSTIDs) appear frequently as oscillating wavesin electron density (i.e: wave-like structure) induced by the presence or passage of Atmospheric GravityWaves (AGW), propagating through the neutral atmosphere and consequently causing fluctuation orperturbations in ionospheric Total Electron Content (TEC) of the ionosphere. This study presentsa statistical observation of MSTIDs using TEC obtained from the Global Positioning System (GPS)receivers located in the northern part of African region. We considered a geomagnetic condition of Kp< 4 during 2008-2016 period of solar cycle 24. The generated heat map of MSTIDs clearly showedthe temporal and spatial variations of their occurrence and further revealed daytime occurrence ofMSTID activities (0600-17:5900 LT) in equinox and winter, while dusk (1800-2000 LT) and nighttime(2100-0300 LT) activities occurred in summer. This was excluded during solar max period in summer(2013-2014), where the MSTID nighttime activities got extended. In this research, some of theMSTID characteristics such as period and wavelength were estimated, the mean values are dominantlybetween 20-55mins and 50-350km respectively, and MSTIDs propagation directions were dominantlytowards equator. The regional distribution of MSTIDs occurrence shows a semiannual variation withpronounced primary and secondary peak in June solstices and December solstices respectively. There isan indication that MSTIDs occurrence increases with solar activities. Keywords: MSTID, ionosphericirregularities.

Page No. 70

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 71

Changes of permeabilities as a result of Hydrate Dissociation in Sand-ClaySediments from Qilian Mountain Permafrost, China

Mengdi Pan mengdpan@gfz-potsdam.de3.1 - Inorganic and Isotope Geochemistry

Mengdi Pan, Yi Wang, Sathish Mayanna, Anja M. Schleicher, Erik Spangenberg, Judith M.Schicks, Xiao-Sen LiGFZ Potsdam, University of Potsdam, Guangzhou Institute of Energy Conversion Chinese Academyof Sciences

Permeability is known as a key factor affecting the effectiveness of gas production from a naturalgas hydrate reservoir. In addition to the lithological effects of the hydrate-bearing sediment itself,the formation and dissociation processes of gas hydrate in the sediments may also have an influenceon the permeability. In this study, samples from a gas hydrate reservoir in the Qilian Mountainpermafrost (borehole DK-8 and SK-2 in northern Muli coalfield) were taken for the permeabilityexperiments. Permeabilities were measured before hydrate formation, with hydrate and also afterhydrate dissociation. The presence of solid methane hydrate in the pores lowers the permeabilitydepending on hydrate saturation. However an unexpected high permeability decrease was observedafter the dissociation of methane hydrate. Six kinds of permeability tests were carried out to detectthe reason for formation damage after hydrate dissociation. The results indicate that the fresh waterreleased from the hydrate dissociation may cause an activation and following the migration of fineparticles which block the pore throats and finally result in a decrease of permeability. ScanningElectron Microscopy (SEM) analysis on the filter papers which attached on the inlet and outlet ofthe core sample provides visible evidence on fine migration. In our study we present the experimentalresults of the permeability tests under different conditions and discuss the potential reasons for ourobservations. One possible explanation for this phenomenon may be that the release of fresh watercauses an increase in the double layer thickness at the water mineral surfaces and therefore increase therepulsion forces between rock particles. This process can release small particles which were attachedto the surface of bigger sediment grains.

Page No. 71

Poster Stand No 72 EGU posters: Poster Session 2: 16:30 – 17:30

Analysis of ocean tide induced magnetic fields — Climate trends and theremarkable role of shelf regions

Johannes Petereit johannes.petereit@gfz-potsdam.de1.3 - Earth System Modelling

Johannes Petereit, Jan Saynisch-Wagner, Christopher Irrgang, and Maik ThomasGFZ Potsdam, Freie Universität Berlin

Previous studies showed that ocean tide induced magnetic fields are sensitive to oceanic temperatureand salinity variations. Based on in-situ observations of oceanic temperature and salinity, a timeseries of global ocean tide induced magnetic field amplitudes has been computed. The time series isanalyzed to compare current developments in the oceanic states with existing climate model scenarios.The preceding studies have investigated the impact of global oceanic warming on ocean tide inducedmagnetic field amplitudes on one hand and the impact of Greenland glacial melting on the other.We combine oceanic temperature and salinity fields covering a time span from 1990 to 2016, withdata of oceanic tidal flow, the geomagnetic field, mantle conductivity and sediment conductanceto determine the relevant magnetic field amplitudes. From the seasonal variability and long termtrends of these magnetic field amplitudes we find indications for both scenarios. The results showthat magnetic field amplitude anomalies caused by oceanic climate variations are ten times largerin shelf regions than in the open ocean. Changes in the oceanic and therefore Earth’s climate willconsequently be observed first there so that climate variations are best monitored with targetedmonitoring techniques. Preliminary results of an validation attempt of these findings by extractingtrends of ocean tide induced magnetic field amplitudes from terrestrial magnetometer observationsare also presented.

Page No. 72

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 73

Empirical approaches for the depth-scaling of CRNS-derived soil moisturetime series

Daniel Rasche daniel.rasche@gzf-potsdam.de4.4 - Hydrology

Daniel Rasche, Andreas Güntner, Theresa BlumeGFZ German Research Centre for Geosciences, Section Hydrology, Potsdam, Germany

Since its invention a decade ago, non-invasive soil moisture monitoring using Cosmic Ray NeutronSensing (CRNS) underwent an extensive development. Several signal correction procedures have beenintroduced and different calibration approaches have been tested and further developed to obtainaccurate soil moisture estimates from the CRNS signal. However, CRNS-based measurements of soilwater content represent an average value over a varying integration volume with a horizontal footprintarea of several hectares and depths up to 30 cm. While field scale soil moisture measurements arehighly beneficial for different hydrological applications, many operations require differentiated soilwater information for individual soil layers, i.e. water budgeting or multi-criteria calibration of rainfall-runoff models at the catchment scale. Therefore, we apply latest correction and calibration proceduresto CRNS time series in the lowlands of north-eastern Germany and test different empirical approachesto depth-scale CRNS derived soil moisture values. Scaling is conducted according to reference timeseries of different depths using TDR soil moisture probes. Empirical approaches are either solely basedon the CRNS soil moisture time series or include physical properties of individual soil layers. Firstanalyses show promising results, although the applied methods may need to be refined to achievehigher accuracies for specific depths. Depending on the environmental characteristics of individualstudy sites, further approaches will be tested that also include other non-invasive techniques for soilmoisture estimation on a similar spatial scale such as GNSS reflectometry and hydrogravimetry.

Page No. 73

Poster Stand No 74 EGU posters: Poster Session 2: 16:30 – 17:30

Timescales of leaf wax biomarker transport and preservation in alluvial riversystems: Rio Bermejo, Argentina

Marisa Repasch marisa.repadch@gfz-potsdam.de4.6 - Geomorphology

Marisa Repasch, Dirk Sachse, Joel Scheingross, and Niels Hovius,GFZ German Research Center for Geosciences, University of Potsdam

Rivers are the primary conduits for organic carbon (OC) transfer from vegetation-rich uplands to long-term sinks, and thus are responsible for significant fluxes among different reservoirs of the carbon cycle.Sedimentary leaf-wax biomarkers can be used to elucidate the mechanisms of transport, preservation,and/or transformation of OC during its passage from source to sink. In this study we evaluate thetimescales of terrestrial leaf wax n-alkane transport from source to sink. Our natural laboratory is theRio Bermejo in northern Argentina, which transports material from the central Andes over 700 kmacross the foreland and out onto the craton without input of foreign material from tributaries. Rapidchannel migration rates are responsible for remobilization of floodplain sediment and terrestrial OC,which is delivered to a large continent-scale river downstream. By sampling suspended sediment, riverbank sediment, and soil from several locations along the length of the Rio Bermejo, and analyzingthe biomarker isotopic composition, we evaluate the geomorphic processes that control the timescaleof fluvial POC transport. Compound-specific 13C measurements show enrichment of terrestrial n-alkanes (C25-C33) with increasing distance downstream, suggesting significant input of 13C-enrichedfloodplain material. We propose that microbial degradation is responsible for preferential preservationof 13C in floodplain sediment over the timescale of hundreds to thousands of years. We expectcompound-specific 14C measurements to show increasing age with distance downstream. Analysis ofmodern and aged river bank sediment samples will determine where and over what timescales leafwax n-alkanes are oxidized by microorganisms. With these data, we will be able to quantify the lossof OC during fluvial transit, enabling carbon cycle models to account for these losses.

Page No. 74

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 75

Seismic surveying to explore the transition zone around caverns in salt rocks

Heike Richter hrichter@gfz-potsdam.de4.2 - Geomechanics and Scientific Drilling

Heike Richter1, Rüdiger Giese1, Axel Zirkler2, and Bettina Strauch2

1Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences, Potsdam, Germany,2K+S Aktiengesellschaft, Kassel, Germany

Salt deposits can be influenced by fluid entries due to geological fracture zones or the solution oftechnical caverns, e.g. as energy storage space. The aim of the seismic surveys within the GEO:Nproject ProSalz is to further investigate these fluid occurrences and their migration into the developingtransition zone between cavity and undisturbed salt rocks by using tomographic and pre-stack migra-tion methods. Two different seismic surveys are performed to image structures in salt rocks close toa geogenic cavern and an artificially created field-test cavern within a salt pillar. Changes within thesalt rocks close to the geogenic cavern are determined by travel time tomography, in particular p-wavetomography and p/s-wave tomography in 2D and 3D. The first evaluation of the seismic data setrevealed an average p-wave-velocity of 4.60 km/s and an average s-wave-velocity of 2.63 km/s in saltrocks. Furthermore, the potential velocity gradient towards the cavernous structure will be evaluatedand compared to geochemical experiments. The signals of reflected waves can possibly be used todistinguish between fluid-filled and dry areas to explore potential fluid pathways within the salt body.Similar methods are used to monitor effects around the field-test cavern by installing a seismic sensorarray around the salt pillar. The seismic monitoring at the salt pillar is performed in the frequencyrange of 100Hz to 14000Hz resulting in a spatial resolution in the cm-range. The main focus of thesemeasurements is to detect the dm-sized field-test cavern within the pillar and to monitor the expectedevolution of a fluid-migration in its vicinity. Due to the application of a similar seismic measurementsystem, the results of the field-test cavern can be directly related to geogenic and technical cavernsand help to improve the process understanding of the multiphase transport (salt-water-gas) in thetransition zone between cavity and solid rock.

Page No. 75

Poster Stand No 76 EGU posters: Poster Session 2: 16:30 – 17:30

Hierarchical Bayesian approach for parameterizing flood damage model forEurope

Nivedita Sairam nivedita@gfz-potsdam.de4.4 - Hydrology

Nivedita Sairam, Kai Schroeter, Heidi KreibichGFZ, potsdam

Reliable and accurate predictions of flood damages are imperative in making efficient risk basedadaption strategies. Hence, flood damage estimation is a crucial step in Flood Risk Management.Damage models can either be based on empirical data from flood events or synthetic/engineeringexpert knowledge. Empirical flood damage models are generally developed using data pertainingto flood characteristics, exposure and reported loss estimates. These models are temporally andspatially localized. However, in practice the models developed for one region are transferred to another,without testing their suitability for the region and purpose. Several validation studies show that thesemodels are associated with high uncertainties when applied to regions outside the area or country forwhich the models were developed. A hierarchical Bayesian approach is implemented for developing aflood damage model by combining empirical flood damage data from multiple regions and events inEurope. This approach tries to estimate losses while accounting for spatio-temporal variations in thedamage processes. The hierarchical model is a multi-level regression model that estimates individualsets of coefficients using the predictors to model the outcomes in each group. Additionally, there isalso a second probability distribution over these group-level parameters that govern the variabilitybetween the groups. In our hierarchical model structure, flood loss is modelled as a function ofwater depth (depth-damage curve) using two levels of groupings – region and event over which thesecond probability distribution for each region lies. The hierarchical model is a middle-ground betweengeneralized (one set of loss estimation parameters for entire Europe) and localized (independent setof loss estimation parameters for each event) models. Hence, the parameters of the hierarchical modelbecome more independent in the presence of abundant data for a specific event. Similarly, when fewdata is available, the parameters shrink closer to the over-arching distribution parameters. Bayesianparameter estimation combined with hierarchical modelling allows quantification of uncertainty ateach level in the hierarchy (region, region-event and household). We validate the predictions of thehierarchical model against popular reference models such as FLEMOps for Germany, Multi-Colored-Manual for UK.

Page No. 76

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 77

Radial anisotropy across Northeastern and Northwestern Himalaya

Shubham Sharma sharma@gfz-potsdam.de2.1 - Physics of Earthquakes and Volcanoes

Shubham Sharma1,2,3, Supriyo Mitra3, Siddharth Dey3, Monumoy Ghosh3, and Sankar NBhattacharya3

1Institute of Earth and Environmental Science, University of Potsdam, 14476, Potsdam, Germany,2GFZ German Research Centre for Geosciences, 14473, Potsdam, Germany, 3Department of EarthSciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, West Ben-gal, India

We jointly model Rayleigh and Love wave group velocity dispersion data along two 2-D profilesacross the India- Eurasian continent-continent collision zone, to estimate the transversely isotropicshear wave velocity structure of the lithosphere. The first profile is south-north across the BengalBasin, the Shillong Plateau, the Eastern Himalaya and the southern Tibetan Plateau. The secondprofile is southwest-northeast across the NW Himalayan foreland, the Kashmir Himalaya and thewestern Tibetan Plateau. For the inversion, we have developed a scheme using Genetic Algorithms(GA). Theoretical dispersion curves are calculated using the algorithm of Bhattacharya (2017). Thestarting model for the inversion is built from existing 1-D models eg. CRUST 1.0 and PREM, for thecrustal and upper mantle layers, respectively. The free parameters in the inversion are layer thickness(H), VSH , ξ, VPH . The corresponding φ and η in each layer is used through empirical relationswith later three free parameters. GA performs a global search of the model space and optimize themisfit between observed and calculated dispersion data using a jointly weighted objective function.We run GA for 40 generations and repeat this process 20 times to obtain 20 best fitting models. Thefinal model is obtained by computing the mean and standard deviation of these 20 best fit models.The variations in the best fitting models provide a qualitative measure of the trade-offs betweenparameters. We perform synthetic tests along the above mentioned 2-D profiles to ascertain themodel recovery and estimate the uncertainties. Results of the synthetic tests reveal less than 10%uncertainties on the layer thickness and velocities. This procedure is being applied to observed dataobtained from the Rayleigh and Love wave group velocity tomography of the India-Eurasia region,and will be presented.

Page No. 77

Poster Stand No 78 EGU posters: Poster Session 2: 16:30 – 17:30

Potash salt composition governs the formation of geogenic caverns

Svenja Steding ssteding@gfz-potsdam.de3.4 - Fluid Systems Modelling

Svenja Steding, Axel Zirkler, Michael KühnGFZ Potsdam, University of Potsdam, K+S Aktiengesellschaft

In Germany, salt deposits play an important role as industrial raw material as well as sites for energystorage. However, in geological fault zones, dissolution of the salt body due to contact with migratinggroundwater may ultimately lead to the formation of geogenic caverns and subsidence of overlyingstructures representing a high risk to active potash mining. Due to the high solubility of potashsalts, cavern growth is facilitated in potash seams compared to solid rock salt. Using the softwarePHREEQC (Parkhurst & Appelo, 2013) the dissolution behavior of potash salt has been investigatedsystematically and the results were compared to field measurements. A titration model for varyingcompositions of hard salt has shown that several components within the potash seam, i.e. halite, areonly partly dissolved, while others, i.e. carnallite, are fully converted into secondary minerals. Duringthat conversion process, brine composition and precipitations mainly depend on the ratio betweenkieserite and sylvite. Several field measurements from a salt mine showed consistency with calculatedbrine compositions, especially for kieserite-rich potash salts. The dissolution process only stops ifwater, kieserite or sylvite is fully depleted. As a consequence, 1 kg of brine can influence several tensof kilograms of potash salt. In a further step, a 1D model was generated in order to characterise brinecomposition across the transition zone between a cavernous structure and unaffected rock. Resultsshow that the brine composition along the transition zone matches the reaction pathway of thetitration model. The zone can be divided into different mineralogical regions, containing secondaryminerals like glaserite, leonite or kainite besides halite. These calculated minerals were also foundaround naturally occurring fault zones. Volume analyses also show that cavern growth requires anopen system with a minimum exchange rate. Furthermore, new void spaces are only formed at thebeginning of the transition zone (close to the center of the cavern). Transferring the modeling resultsto a mine is supposed to facilitate an early detection as well as a safe long-term retention of cavernswithin salt rock.

Page No. 78

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 79

Passive seismic monitoring at the Los Humeros geothermal field, Mexico:preliminary results.

Tania Toledo taniat@gfz-potsdam.de4.8 - Geoenergy

T. Toledo1, E. Gaucher2, Malte Metz1, Philippe Jousset1, Hansruedi Maurer3, Angel Figueroa4,Marco Calo5

1Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum (GFZ), Section 4.8 Geoenergy,Potsdam, Germany, 2Karlsruhe Institute of Technology (KIT), Institute of Applied Geosciences - Geo-thermal Research, Karlsruhe, Germany, 3ETH Zurich, Switzerland, 4Universidad Michoacana de SanNicolás de Hidalgo, Mexico, 5Universidad Nacional Autónoma de México, Mexico

For the period between September 2017 and September 2018, an extensive passive seismic monitoringexperiment was carried out in the Los Humeros geothermal field in Mexico. A seismic array consis-ting of 23 broadband and 20 short period stations was deployed in the framework of the EuropeanH2020 GEMex project to collect and process seismic data that will aid in the characterization of theunderground structures and behavior of the currently exploited geothermal field. The Los Humerosgeothermal field is one of the largest geothermal fields in Mexico currently operated by the FederalElectric Comission and is located in the state of Puebla near the border of Veracruz. In this work,we filtered the continuous seismic records and performed a recursive STA-LTA algorithm to detectmicro-seismic events mainly associated to exploitation activities. Manual review and picking lead tothe location of around 500 local events mainly clustered around injection wells. They are mainly loca-ted at depths between 1 and 3.5 km depth. The resulting catalogue was used to derive a 1D velocitymodel, which will be later on used for obtaining lateral variations of P- and S-wave velocities.

Page No. 79

Poster Stand No 80 EGU posters: Poster Session 2: 16:30 – 17:30

Upper-plate normal faulting on the island of Kythira and its relation to theHellenic subduction-thrust faulting

Violeta Veliz veliz@gfz-potsdam.de4.1 - Lithosphere Dynamics

Violeta Veliz1, Vasiliki Mouslopoulou1,2, Andrew Nicol3, Onno Oncken1

1GFZ-Potsdam, 2National Observatory of Athens (NOA), 3University of Canterbury

Numerous forearc regions along active convergent margins worldwide experience uplift due to thrustfaulting in the plate-interface zone. While compressional kinematics drive deformation at depth, theupper-plate on several forearc settings is dominated by extension and associated normal faulting. Here,we focus on Kythira, an island situated on the forearc of the Hellenic margin between Peloponneseand Crete, to study the interaction of these two simultaneously active fault systems over varioustimescales. Preliminary analysis of displacements, lengths and displacement rates for Quaternary(1± 0.5 Ma) and post-glacial (16.5± 0.5 kyr) time-intervals on 39 individual active faults on Kythira,provide information on the kinematics and normal fault growth in the upper-plate. Data were obtainedby a combination of field measurements, using tape-measure and laser scanner, and analysis of ahigh-resolution (5m) Digital Elevation Model (DEM). Based on fault orientations, sizes and cross-cutting relationships, we define three main sets of faults: 1) The Master faults (n=4), which havea predominately NW–SE strike and clear post-glacial scarps. These faults are the longest (up to20 km), often traversing the entire island and extending offshore. 2) The Secondary faults (n=21),with either N-S or E-W strike, that often terminate against the Master faults with angles of ∼ 30◦

degrees. The secondary faults appear to have accommodated the largest post-glacial displacements.3) The Quiet faults (n=14), which are active features with a clear topographic signature, yet, withoutpost-glacial activity. These faults are characterized by small lengths and displacements. Collectively,normal faulting on Kythira produces an extension rate of 2.5 – 3mm/yr in a margin-normal direction,with strains increasing southwestward. This trenchward increase in the strain gradient may indicatethat upper-plate faulting forms on the hanging-wall of steep splay-thrust faults (the tip of whichdefines the Hellenic Trough) due to gravitational collapse, a process that requires long-range faultinteractions.

Page No. 80

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 81

Multi-Array Back-Projection as a High-Resolution approach: Application tothe 2007 Mw 7.7 Tocopilla and 2018 Mw 7.5 Palu earthquakes

Felipe Vera fvera@gfz-potsdam.de2.4 - Seismology

Felipe Vera, Frederik Tilmann, Joachim SaulGFZ Potsdam, Freie Universität Berlin

Since the 2004 Mw 9.1 Sumatra-Andaman earthquake, back-projection imaging of earthquakes basedon high-frequency emissions has become a complementary method to Finite Source Inversions, pro-viding information related to the rupture area, rupture velocity, and energy distribution in time andspace without any prior fault geometry knowledge requirements. Further developments have allowedits extension from a time-domain approach to frequency-domain methods while multiple applicationshave, for example, characterized major subduction zone earthquakes, aftershocks detection, complexruptures, and intermediate-depth earthquakes among others. However, its dependency on large arrayshas severely limited azimuthal coverage of many events, exacerbating artifacts such as the so-called“swimming artifact” and others related to source effects. Here we extended the traditional time-domainback-projection with a multi-array approach, which harnesses regionally distributed seismic stations inaddition to the large-scale arrays usually employed to widen azimuthal coverage. The method involvestraditional dense arrays and multiple groups of stations acting as complementary arrays, whose contri-bution to the solution depends on their azimuthal distribution. Additionally, we included the analysisof multiple seismic phases in the back-projection algorithm to reduce source effects, specifically, thosecaused by pP phases for deepest earthquakes of the shallow-depth segment (d < 70 km). Our analysisis suitable to be standardized and automated for near-real-time applications. We tested the procedurewith two major earthquakes. The first is the 2007 Mw 7.7 Tocopilla earthquake. We have calibratedthe travel time corrections with some of the large aftershocks of this event in order to be able tointerpret the rupture history within their context. We found the high-frequency rupture emissions(0.5 – 2.0Hz) have encircled the dominant asperities along the fault area with the cumulative energybeing emitted updip to the coseismic slip area, which can be associated with the well-described dipsegmentation acting as a barrier in this region. Our second analysis involved the strike-slip ruptureof the 2018 Mw 7.5 Palu earthquake where we identified a prominent super-shear rupture (4.1 km/s)from the epicenter to the south which is exceptionally well correlated with the trace of the activefault identified from the Advanced Land Observation Satellite-2 (ALOS-2) interferograms. The me-thod revealed important high-frequency peaks centered at Palu city and far away from the epicenter(∼140 km) providing a clue to link back-projected energy emissions with potential damages areas.

Page No. 81

Poster Stand No 82 EGU posters: Poster Session 2: 16:30 – 17:30

Controlling parameters of a mono-well high-temperature aquifer thermalenergy storage in porous media, northern Oman

Christian Wenzlaff christian.wenzlaff@gfz-potsdam.de4.8 - Geoenergy

Christian Wenzlaff, Felina Schütz, Gerd WinterleitnerGFZ Potsdam, GFZ Potsdam, University of Potsdam/GFZ Potsdam

Aquifer thermal energy storage (ATES) as a complement to fluctuating renewable energy systems isa promising technology to guarantee a continuous energy supply. A mono-well system, where the wellscreens are separated vertically within one aquifer, is investigated to realize an underground storagein northern Oman. In this study, we investigated the impact of conductive thermal inference andhydraulic short-circuiting between injection and extraction well screens on the heat recovery factor(HRF) of a planned high-temperature (∼ 100 ◦C) ATES system within the Seeb aquifer. The storageshall cover the energy demand of a planned thermally driven cooling system during night times.We analysed different controlling parameters: the vertical screen-to-screen distance, the impact of ano-flow barrier between the screens, aquifer thickness and vertical heterogeneities of the hydraulicconductivity. Simulation results indicate that using a mono-well ATES system could guarantee acontinuous cooling process. The highest HRF (88% after one year) is reached with a 10 m screen-to-screen distance within a 20m thick aquifer, where no hydraulic breakthrough is observed but aconductive thermal interference between the screens. This indicates that to a certain degree thermalinference enhances the performance of the storage, when the temperature of the cold and warm wellscreen are both above the natural reservoir temperature. Aquifer heterogeneities reduce this thermalinterference with a negative impact on the efficiency. Further, the fluid transfer is governed by theheterogeneous hydraulic conductivity distributions, which has a major impact on the heat distributionwithin the aquifer and leads additionally to lower HRF-values.

Page No. 82

EGU posters: Poster Session 1: 11:00 – 12:00 Poster Stand No 83

Comparative analysis of scalar upper tail indicators

Luzie Wietzke lwietzke@gfz-potsdam.de4.4 - Hydrology

L. M. Wietzke, B. Guse, H. Kreibich, L. Gerlitz, S. Vorogushyn, B. MerzGFZ German Research Centre for Geosciences, Section Hydrology, Potsdam, Germany

Heavy tail phenomena have been discussed in various branches of science reaching from finances,economics and environmental sciences to natural hazard research and hydrology. While several defi-nitions of heavy tail behavior of distributions coexist, it can generally be characterized by a higherprobability for the occurrence of extreme events compared to bounded- and light-tailed distributions.In hydrological studies, scalar measures of heavy-tail behavior are often applied to compare the uppertail behavior of different flood or heavy precipitation distributions. However, there is no comparativestudy of these indicators so far. In our study, we aim to compare four scalar indicators of heavy-tailbehavior and assess their immanent properties: The Shape parameter of the GEV, the Obesity index,the Gini index and the Upper tail ratio. Our analyses with synthetic data include examining the im-pact of sample size and location shifts as well as testing for scale invariance. Further, we introducethe surprise factor which is defined as the probability that a known HQx event is strongly undere-stimated by observations to provide a benchmark for heavy-tail behavior. Our results show that allfour indicators exhibit a monotonic relation to the surprise factor. These relations highly depend onthe Lorenz asymmetry coefficient which is a measure for the arrangement of extremes in the uppertail. For distributions with symmetric Lorenz curves, the indicators are partially linear correlated. Wefurther found that the indicators behave differently under change in location parameters and scaling.Taking into account the different properties of the indicators, the appropriate choice of an upper tailindicator depends on the specific research questions as well as the respective definition of heavy-tailbehavior and is facilitated by results of this study.

Page No. 83

Poster Stand No 83 EGU posters: Poster Session 2: 16:30 – 17:30

Page No. 84

EGU talks

EGU talk Session 1: 09:30 – 11:00

EGU talk Session 2: 14:00 – 14:35

EGU talks Session 1: 09:30

Source array configuration and applications in crustal structure studies

Nasim Karamzadeh karamzad@gfz-potsdam.de2.1 - Physics of Earthquakes and Volcanoes

Nasim Karamzadeh, Torsten Dahm, Frank Krüger, and Sebastian HeimannGFZ and University of Potsdam

Based on the reciprocity theorem of Green’s function, a number of seismic sources recorded at singlestation are considered as a „source array“ (SA), in an analogy of a receiver array (RA). To composean SA requires that the coordinates, origin times, and depths of the sources to be precisely known.Furthermore, akin to the waveform coherency requirement for an RA, SA waveform needed to becoherent. This implicitly implies that the source mechanisms of all events should be similar or theeffect of waveform dissimilarity should be corrected. The positive attribute of an SA is the possibilityof forming a 3-D array, that allows for full slowness field calculation of the phases leaving the sourceregion, the study of the near-source structure and the wavefield travel pass. In addition, withoutbearing the extra cost of sensor installation, array processing methods are applicable. On the otherhand, the fulfilment of all prerequisite conditions is difficult in practice. In this work, the aim isto facilitate the use of seismic source array beamforming in order to image the crustal interfacesproducing strong converted/reflected phases, given a well-located events catalog. We propose theuse of an optimization technique to find the SA elements. Using optimization technique allows forquantitative evaluation of the related prerequisites by defining suitable criteria. We suggest threecriteria/objective functions: (1) to ensure the high resolution of SA beamforming in 3-D slownessspaces, that can be evaluated using either by synthetic or real data, (2) to check the waveformssimilarity over the array elements, and (3) to select events with lower location error. The locationof the interface in the velocity model, that makes the converted/reflected phases, e.g. sp-phases, isretrieved by a grid search method once the SA elements are found. Considering each grid point as ahypothetical interface for all source element, the theoretical travel time of the sp-phase is estimatedby the sum of s-phase and p-phase. The former travels the distance between the source and interfaceand the latter travels the distance between the interface and the receiver. Then, sp-phases windowsare selected from the waveforms and stacked and the corresponding semblance value is calculated andis assigned to that grid point. The procedure is repeated for all grid points and the maximum valueof the semblance of all grids indicates the location of the interface. We applied the approach in theNorth Bohemia Vogtland, for which evidences of converted phases have been approved from previousstudies, and a well-located catalog of earthquake swarm is available. We locate the different segmentsof the interface with a population of source arrays and considering different station locations. Theaccuracy of the approach and the obtained results are convincing that the method is applicable tostudy the crustal structure and the location of crustal interfaces when the strong converted phasesare observed in the data and a well-located catalog is available.

Page No. 86

EGU talks Session 1: 09:45

Potentials for Power-to-Gas based subsurface energy storage in China

Jianli Ma jianlima@gfz-potsdam.de3.4 - Fluid Systems Modelling

Jianli Ma, Qi Li, Natalie Nakaten, Michael KühnInstitute of Rock and Soil Mechanics Chinese Academy of Sciences, University of Chinese Academyof Sciences, GFZ Potsdam, University of Potsdam

The renewable energy power generation capacity has been rapidly increasing in China recently. Ho-wever, the contradiction between power supply and demand is becoming increasingly prominent dueto the intermittency of renewable energies. Meanwhile, the mitigation of carbon dioxide (CO2) emis-sions in China needs immediate attention. Power-to-Gas (PtG) based subsurface energy storage, aclosed carbon cycle based on an extension of „power to gas to power“ technology, can convert surpluselectricity into combustible gases by consuming CO2 and meet the requirements of long-term energystorage with its large capacity. A discussion of the entire PtG energy storage technology processand the current research progress are presented here to show the details of this innovative idea. Thecomparative study of different geological storage schemes shows their progress and limitations. A fullinvestigation of the distribution and implementation of global PtG and carbon capture and storage(CCS) demonstration projects provides references for the application in China. Based on some appliedand modified techno-economic modules and ecological effects analysis, the opportunities and challen-ges are coexisting in the application of PtG based subsurface energy storage in China. However, thesite selection, energy efficiency, and the economy still need an adequate discussion. To increase thepossibility of applying PtG based subsurface energy storage in China, innovation of electrolysis andmethanation technology, system energy efficiency optimization, energy gas storage and transportati-on risk control, leakage pre-warning system, techno-economic feasibility, ecological effects, geologicalconditions, the distribution of carbon dioxide emission source, the distribution of existing gas storage,the distribution of the West-east pipeline project (WEPP), and the impact of the policy should all becomprehensively considered.

Page No. 87

EGU talks Session 1: 10:00

Scandinavian Lithosphere Structure derived from Ambient Noise and Sur-face Waves

Alexandra Mauerberger gassner@gfz-potsdam.de2.4 - Seismology

Alexandra Mauerberger1, Hamzeh Sadeghisorkhani4, Frederik Tilmann1, Olafur Gudmundsson3,Valerie Maupin2

1Helmholtz Centre Potsdam German Research Centre for Geosciences GFZ, Germany, 2University ofOslo, CEED, Norway, 3University of Uppsala, Sweden, 4Department of Mining Engineering, IsfahanUniversity of Technology (IUT), Isfahan, Iran

The western rim of Scandinavia is characterized by the Caledonian mountain range with topogra-phy up to 2500 m. Since this region lacks recent compressional tectonic forces, it provides a greatopportunity to study the geodynamic evolution of crustal and upper mantle structures at today’spassive continental margins. Together with the ScanArray network we use data from previous andpermanent projects, in total more than 200 stations, for a surface wave tomography of the area usingboth earthquake and ambient noise data. In previous studies, an unusually thin crust and shallowlithosphere-asthenosphere boundary (LAB) have been found beneath the high-topography of westernNorway, where a clear crustal mountain root seems to be absent. The lower topography regions ofeastern Norway and Sweden, however, reveal a thicker crust, in contrast to the principles of Airyisostasy. Lower seismic velocities than expected have been found with a sharp transition to highervelocities beneath Sweden. Beamforming of Rayleigh surface waves yields average phase velocitiesfor all Scandinavia and several of its sub-regions. A remarkable cos(1θ) phase velocity variation withazimuth is estimated for periods >35 s. Since this effect can be seen in northern and southern Scan-dinavia but not in the central area this might indicate a dipping LAB related to varying topographyfrom North to South. From previous studies it is known that the cos(1θ) feature and the dippingLAB are also seen at the eastern rim of the Appalachians - however mirrored. Both mountain rangesexhibit the same orogeny. Phase velocity maps were derived with the two plane wave method. Ambientnoise were analyzed using a transdimensional MCMC Bayesian inversion. We use a transdimensionalBayesian method to invert for the VSV structure. The Moho below Northern/Lofoten region is highlyundulated but a crustal root of the high topography is not present. The Lofoten peninsula showsvery low crustal and lithospheric VSV with a shallow Moho around 20 km at the continental margin.The LAB is deepening from west to east with a sharp kink both in the South (120 km depth) andthe North (150 km depth). The LAB in the North is even more undulated and related to a gravityanomaly imaged as high-velocity spot. However, the central area shows rather smooth varying struc-tures from west to east. Additionally, we find evidence for a MLD around 150 km depth beneath thePaleoproterozoic Baltic Shield.

Page No. 88

EGU talks Session 1: 10:15

High sediment export from a trans-Himalayan semi-desert driven by lateHolocene climate change and human impact

Johanna Menges menges@gfz-potsdam.de4.6 - Geomorphology

Johanna Menges1, Niels Hovius1,2, Christoff Andermann1, Michael Dietze1, Charlie Swoboda2,Kristen Cook2, Andrea Vieth-Hillebrand3, Stephane Bonnet4, Tony Reimann5, and DirkSachse1

1GFZ German Research Centre for Geosciences, section 4.6 Geomorphology, Potsdam, Germany(menges@gfz-potsdam.de), 2Institute of Geosciences, University of Potsdam, Potsdam, Germany,3GFZ German Research Centre for Geosciences, section 3.2 Organic Geochemistry, Potsdam, Germa-ny , 4GET CNRS Univ Toulouse, GET, UMR 5563, Toulouse, France, 5Soil Geography and Landscapegroup & Netherlands Centre for Luminescence dating, Wageningen University, The Netherlands

Sediment export rates are sensitive to changes in climate, vegetation and human impact, but thedirect response of a given landscape to such changes is difficult to unravel. Here, we report a stronglandscape response to a disturbance of a stable, soil covered landscape in a trans-Himalayan valley,which was pushed over an eco-geomorphic tipping point resulting in fast and widespread erosion.We then identify potential drivers for this transition. The upper Kali Gandaki (KG) river valley inNepal drains the southern edge of the Tibetan plateau in the rain shadow of the High Himalayas,where a scarcely vegetated semi-desert is dissected by deep gullies. These badlands formed in a grabenstructure storing large amounts of unconsolidated sediments which provide a source of erosion productto the high stream-power river. Due to the high erodibility of this material, the region is particularlysensitive to changes in climate and land use. At the outlet of the upper valley, we estimate thatriver suspended sediment concentrations are up to two orders of magnitude higher for a given riverdischarge than downstream in the monsoon dominated High Himalayan river segment. Even thoughprecipitation rates are low in the upper valley (160mm/yr to 250mm/yr) and discharges rarelyexceed 100m3/s, we show that modern erosion efficiency is around five times higher than in thesteep and wet, landslide dominated southern part of the catchment. In stark contrast to this modernsetting, widespread occurrence of paleosol horizons reflects the persistence of geomorphologicallystable conditions during the Holocene until 2.4 ka based on OSL and 14C ages. What pushed thislandscape from a soil covered stable state into the erosional state observed today? We investigatedhuman land use and climate change as possible drivers of this transition. Human impact on thelandscape has been suggested from 5.4 ka onwards (Miehe et al., 2009) and an increased occurenceof archeological sites and evidence of grazing animals has been reported from 3 ka (Simons et al.,1994).We estimated paleo-hydrological conditions using the hydrogen isotopic composition of plant lipids(δDwax) extracted from the paleosol horizons in the upper KG valley (3500 – 4100m asl., n=24). δDwaxvalues range from 214 h to 236 h which is offset by 40 h± 6 h from the δDwax values of modern shrubleaves sampled at the paleosol sites and modern topsoils sampled along the wetter fringes of the valley.This strongly suggests that soil formation took place under substantially wetter conditions, i.e. anenhanced monsoonal precipitation in the past. The subsequent Late Holocene drying trend combinedwith human land use likely reduced vegetation cover which then initiated the transition to badlanddevelopment observed today. Current erosion rates suggest a catchment-average surface lowering rateof one meter per 1000 years, resulting in a strong and irreversible degradation of the landscape andits soils. Miehe G, Miehe S, Schlütz F. (2009) Quat Res. doi:10.1016/j.yqres.2009.02.004. Simons A,Schon W, Shrestha SS. (1994) Anc Nepal, J Dep Archaeol.

Page No. 89

EGU talks Session 1: 10:30

Improving magnitude scale consistency through boosting tree regressionand 3D source correction

Jannes Münchmeyer munchmej@gfz-potsdam.de2.4 - Seismology

Jannes Münchmeyer, Dino Bindi, Christian Sippl, Frederik Tilmann, Ulf LeserGFZ Potsdam, HU Berlin, FU Berlin

Local magnitudes are typically determined from amplitude measurements that are naturally noisy. Toimprove the accuracy of magnitude estimations, measurements from multiple stations are combined.As many measurements are often not available for near real time applications, we developed a methodto achieve consistent magnitude estimations even in the presence of only few stations. We achievethis by leveraging the large scale IPOC catalog (Sippl et al. 2018) with > 100,000 events, coveringseismicity in the northern Chile subduction zone between 2007 and 2014, through a combination ofoptimization and machine learning techniques. We propose a three step setup, consisting of a featureextraction, a feature correction and a boosting tree regression combining multiple features. In thefirst step we extract a multitude of features, including peak and coda values of displacement, velocityand acceleration as well as energy from all reasonable components. In the second step we correctthe measurements for source, station and path effects using multiple non-parametric approaches. Toaccount for attenuation and geometric spreading we define a non-parametric function dependent onthe epicentral distance and event depth. We further define an adaptive non-parametric 3D source andpath correction function for each station based on a k-nearest neighbor regression. In the third stepwe use a boosting tree regression to combine multiple features and further reduce variance. Comparedto a standard, non-parametric, 1D correction function, our method reduces uncertainties by up to56%, of which 15%– 25% can be attributed to the improved correction functions, while boostingtree regression give a further reduction of 35%– 50%. By analyzing the boosting tree we show thatthe variety of features is essential for the quality of the regression. Especially coda and P wave derivedfeatures are key factors to reduce uncertainties. To further elucidate the information extractable froma single station trace, we train another boosting tree on the uncorrected features. This regressionyields magnitude estimates with uncertainties similar to the single features after correction.

Page No. 90

EGU talks Session 2: 14:00

Mass distribution across the Alpine lithosphere - Results from a gravityconstrained model of the Alps and their forelands

Cameron Spooner spooner@gfz-potsdam.de4.5 - Basin Modelling

Cameron Spooner, Magdalena Scheck-WenderothGFZ Potsdam

Although crustal and sub-crustal structures in the Alps are some of the best studied of any orogenin the world, different hypotheses still exist regarding plate architecture and the nature of the sub-duction system. Additionally, rheological configurations of the different crustal units and lithosphericmantle, isostasy in the orogen-foreland system, and variations of flexural rigidity along and across themountain belt, are at the present-day, poorly constrained with relation to spatial patterns of seismicityand deformation. The primary goal of INTEGRATE, a project in the DFG priority program MountainBuilding in 4 Dimensions, as part of the AlpArray initiative, is to provide insights into these questionsby integrating different 3D modelling techniques. Here we present a gravity constrained, 3D, densitydifferentiated, structural model of the Alps and their respective forelands derived from integratingnumerous existing geological and geophysical datasets. Results indicate the existence of lateral hete-rogeneities within the crust of the studied area, particularly in regards to the difference in thicknessand density of the European and Adriatic crusts. Within the plates, some density heterogeneitiescorrespond to well-studied tectonic features such as the Vosges, Black Forest and Bohemian massifs,along with the Ivrea body. However, in keeping with similar modelling works, the location of thesedensity contrasts do not always correspond to present day tectonic structures, instead indicating olderinherited crustal features. A positive correlation between these inherited crustal density contrasts andpresent day deformation maps of the region was identified, a trend not noted prior.

Page No. 91

EGU talks Session 2: 14:15

A combined neural network- and physics-based approach for modeling theplasmasphere dynamics during extreme geomagnetic events

Irina Zhelavskaya irina.zhelavskaya@gmail.com2.8 - Magnetospheric Physics

Irina Zhelavskaya1,2, Nikita Aseev1,2, Yuri Shprits1,2, Maria Spasojevic3

1GFZ Potsdam, 2University of Potsdam, 3Stanford University

Plasmasphere is a torus of cold plasma surrounding the Earth and is a very dynamic region. Itsdynamics is driven by space weather, and having an accurate model of the plasmasphere is veryimportant for wave-particle interactions and radiation belt modeling. In the recent years, feedforwardneural networks have been successfully applied to reconstruct the global plasmasphere dynamics inthe equatorial plane [Bortnik et al., 2016, Zhelavskaya et al., 2017, Chu et al., 2017]. These neuralnetwork-based models have been able to capture the large-scale dynamics of the plasmasphere suchas plume formation and the erosion of the plasmasphere on the night side. However, neural networks(NNs) have one limitation. When data is abundant NNs perform really well but when the data islimited or there is no data at all, which typically happens during extreme geomagnetic storms, thenNNs do not perform well since these data are underrepresented in the training set and NNs cannot learnfrom the limited number of examples. This limitation can be overcome by employing physics-basedmodeling during the periods of high geomagnetic activity. Physics-based models perform stably duringhigh geomagnetic activity time periods if initialized and configured correctly. In this work, we show thecombined approach to model the global plasmasphere dynamics that utilizes advantages of both neuralnetwork- and physics-based modeling and produces accurate global plasma density reconstructionduring extreme events. We present the examples of the global plasma density reconstruction for anumber of extreme geomagnetic storms that occured in the past including Halloween storm in 2003.We validate the global density reconstructions by comparing them to the IMAGE EUV images of theHe+ particles distribution in the Earth’s plasmasphere for the same time periods.

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PICO

PICO talks: 09:30 – 11:00

PICO Presentation 1: 11:00 – 11:30

PICO Presentation 2: 11:30 – 12:00

PICO talk: 10:50 & Presentation: 11:00 – 11:30

Microbiology of the terrestrial ‘plastisphere’ - enrichment and characteriza-tion of plastic-associated microbial communities

Joana MacLean jmaclean@gfz-potsdam.de3.7 - Geomicrobiology

Joana MacLean, S. Mayanna, Fabian Horn, D. Wagner and S. LiebnerGFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam, Section 3.7 Geomicrobio-logy, Potsdam, Germany. GFZ German Research Centre for Geosciences, Helmholtz Centre Potsdam,Section 3.5 Grenzflächen-Geochemie, Potsdam, Germany. Institute of Geosciences, University of Pots-dam, Potsdam, Germany. Institute for Biochemistry and Biology, University of Potsdam, Potsdam,Germany.

In soils, microorganisms are involved in degradation processes of both natural and synthesized material.The overabundance of plastic debris and its accumulation in land and waters creates new geologicalproperties where soil profiles contain layers of fragmented plastics of various types and origins. Stillin its early stage of research, the plastisphere was first suggested as a distinct microbial habitat bystudies carried out on aquatic plastic debris and very few studies have proposed a similar phenomenonfor terrestrial ecosystems. The objective of this study is to characterize the microbial communitiesin plastic-contaminated soil and to test the biodegrading potential of both bacterial strains andconsortia in vitro in order to get a deeper understanding of bacteria-driven degradation of plastics insoil. For this purpose, plastic debris and soils retrieved from two recycling plants and an abandonedlandfill were used as substrate to isolate plastic-associated microbes on medium containing syntheticpolymer as only carbon source. The isolated strains are being characterized and incubated withPolyethylene foil and powder. Biodegradation of these plastic specimens will be explored by SEMimaging, CO2 production and weight-reduction. Furthermore, chemical changes on the polymer levelwill get analyzed with pyrolysis TED-GC/MS and measurements of other polymer specific propertiesby our project partner BAM Berlin. By using Illumina paired-end sequencing (NGS) as a secondculture-independent approach, the diversity and structure of the bacterial community are elucidateddirectly from plastic-soil samples retrieved from around the recycling plants. Combining the findings ofboth the NGS analysis and the isolation of specific microbial strains on plastic will firstly describe theplastic-associated microbial community in soil and help understanding the essential biodegradationprocesses of littered plastic in terrestrial habitats.

Page No. 94

PICO talk: 10:52 & Presentation: 11:30 – 12:00

Magnetic Field Characteristics Observed on the Ground Reliably ClassifyHistorical Geomagnetic Storm Drivers

Leonie Pick leonie.pick@gfz-potsdam.de2.3 - Geomagnetism

Leonie Pick, Frederic Effenberger, Irina Zhelavskaya, Monika KorteGFZ Potsdam, Section 2.3 Geomagnetism & Section 2.8 Magnetopsheric Physics

Satellite observations of the upstream solar wind at L1 show that geomagnetic storms are drivenby two large-scale structures: interplanetary coronal mass ejections (ICMEs) and co-rotating/streaminteraction regions (CIRs/SIRs). Geomagnetic observatory data provide an extensive archive of stormsthat occurred throughout the last 11 solar cycles. We have designed a statistical classifier that usesthis ground-based resource to determine storm drivers back to 1930, i.e. well before the satellite era.Around 7500 storm events (target set) fall below the detection threshold of the long-term stable geo-magnetic Hourly Magnetospheric Currents index (HMC, Pick et al., JGR, under revision). For ∼ 7%of these events the driving mechanism is known from satellite observations (training set). Apart fromHMC, the input data consists of the globally distributed mid latitude HMC observatory time series,from which several discriminative features are derived. Among the most important ones are HMCitself, the correlation coefficient of magnetic disturbance at dawn and dusk and the variability of thedisturbance change at dawn, both for a 24-hour window after the storm peak. The binary classi-fication task is carried out by a logistic regression model, which performs significantly better thanchance on the training set (Matthews correlation coefficient ∼ 0.5). On the target set, we obtaina CIR/SIR to ICME ratio around two with an occurrence pattern dominated by CIRs/SIRs at solarminima and ICMEs at solar maxima. Our successful classification of past storm drivers implies thatsimilar magnetic field features could be used in solar wind predictive models.

Page No. 95