PROJET ANR « STRAP »SYNERGIE TRANSDISCIPLINAIRE POUR REPONDRE AUX ALEAS LIES AUX PANACHES VOLCANIQUES

WORKPACKAGE 2 – CONVECTIVE PLUMES: FLUXES, DYNAMICS AND MODELLING

STRAP Meeting, Saint Denis, December 4, 2015

Andrea DI MURO, Nicolas VILLENEUVE & OVPF teamObservatoire Volcanologique du Piton de la Fournaise (OVPF)

Institut de Physique du Globe de Paris (IPGP)

SOURCE CONDITIONS

WP2B Gas and aerosol budget from small size volcanic plumes(A. Di MURO, S. MOUNE, A. HARRIS, N. VILLENEUVE)

B2. Source magma volatile budget (composition, fluxes) and pre-eruptive concentration –link with time evolution of eruptive activity (IPGP / OPGC)

B3. Near-vent gas and aerosol budgets (insight on sulfur excess problem) (OPGC/IPGP)

Milestones (2015)

A. 1 Eruption in 2014 (June); 4 eruptions in 2015 (February; May; July; August)

B. Source data collection- 110 solid samples (55.3 kg)

- 22 near-field MultiGaS measurements- Permanent and portable DOAS + MultiGaS data acquisition/treatment

- Analysis of June 2014 melt inclusions-OMI SO2 satellite data

MAIN OBJECTIVE: REDUCE UNCERTAINTIES IN SOURCE TERMS- MASS DISCHARGE RATE- HEAT FLUX- GAS COMPOSITION- GAS – SOLID PARTITION- PLUME HEIGHT

METHOD: REAL – TIME OBSERVATIONS AT THE MICROSCALE OF DILUTE PLUMES.INTEGRATION WITH THERMODYNAMIC MODELS OF MAGMA ASCENTAND DEGASSING.

MICROSCALE OBSERVATIONS (< 2 km)

MICROSCALE α−β : SO2 OPTICAL DEPTH (DOAS; PERMANENT AND PORTABLE)PLUME HEIGHT (DOAS NETWORK)IR

MICROSCALE γ : GAS SAMPLING (MULTIGAS)SOLID SAMPLING (LAVA; PYROCLAST)IR

MAGMA ASCENT AND DEGASSING CONSTRAINED BY MINERAL, MELT AND FLUIDINCLUSION DATA

Start End Duration(days)

Duration seismic crisis (min)

Where Volume (Mm3)

20/06/2014 – 21H35 21/06/2014 – 17H09 0.8 76 / 75 SSE (3F / 1C) 0.4

04/02/2015 – 06H50 15/02/2015 -18H30 11.46 100 / WSW (3F / 2C) 3

17/05/2015 – 09H45 30/05/2015 – 16H50 12.70 155 / 45 S& SE (4 + 3F / 2C)

8

31/07/2015 – 05H45 02/08/2015 – 7H15 2.06 90 / 80 NNE (3 F /1 C) 4

24/08/2015 – 14H50 31/10/2015 – 12h20 69 100 / 41 SSW + W (4 F/ 3C) > 50

SOURCE CONDITIONS (MAGMA FLUXES)

Courtesy of D. Coppola (MIROVA)

2B.2 SOURCE VOLATILE BUDGET; SOLID SAMPLES

SAMPLES:- HIGH TEMPERATURE LAVA (WATER QUENCHED)- MID-LOW TEMPERATURE LAVA (NO WATER QUENCHING)

- BOMBS (WATER QUENCHED)- BOMBS (NO WATER QUENCHING)- PYROCLASTS (ON FABRIC BLANKET)

PRELIMINARY RESULTS POINT TO :A) HOMOGENEOUS MAGMA (FEBRUARY, JULY)B) HETEROGENEOUS MAGMA (JUNE, MAI, AUGUST)

C) INVOLVEMENT OF VARIABLY DEGASSED (FACTOR 2.8) SHALLOW MAGMAS (

2B.3 NEAR FIELD GAS MEASUREMENTS (DOAS)

4.3 asl

OMI SO2 dataset (http://so2.gsfc.nasa.gov)

PORTABLE MULTIGAS (RH, P, T, CO2, H2S, SO2)

GROUND BASEDHELICOPTER

DRONECOUNTS: MAX 1 h ca; 0,1 Hz

- DENSE PLUME FROM THE VENT

- DILUTED PLUME FROM THE VENT

- LAVA TUNNEL EMISSIONS

- DILUTED PLUME FROM THE LAVA

- HIGH TEMPERATURE FUMAROLES

- LOW TEMPERATURE FUMAROLES

COUPLING WITH SO2 FLUXES (DOAS) WILL PROVIDE H2O, CO2 AND POSSIBLY H2S FLUXES

2B.3 NEAR VENT GAS MEASUREMENTS

2016: Add halogen and trace metals output

2B.2 M1 (C. BENDIMERAD – IPGP; TUTORS: A. DI MURO; N. METRICH)INITIAL AND RESIDUAL VOLATILE CONTENTS (PETROLOGICAL METHOD)STORAGE PRESSURE AND TEMPERATURE AND MAGMA DEGASSING

2B.3 M2 (R. SPALLANZANI - LMV; TUTORS: S. MOUNE; A. DI MURO)THERMODYNAMIC MODELING OF MAGMA DEGASSINGCORRELATION OF MULTIGAS AND GEOPHYSICAL DATASETS

« BACKGROUND DATASETS »MAGMA BULK COMPOSITION

CRYSTAL CONTENT AND COMPOSITIONPRODUCT TEXTURES (MICROLITES; VESICULARITY; CONNECTIVITY, DENSITY)

ERUPTION DURATIONTIME EVOLUTION OF EXPLOSIVE AND EFFUSIVE ACTIVITY

STEADINESS OF ERUPTIVE CONDITIONSLAVA OUTPUT RATE

TOTAL VOLUME OF ERUPTIVE PRODUCTS (CONE; LAVA)

TIME EVOLUTION OF GEOPHYSICAL SIGNALSSEISMIC HYPOCENTERS

SEISMIC SIGNAL INTENSITY AND FREQUENCY DISTRIBUTIONINFLATION – DEFLATION CYCLES

DATA TREATMENT

EGU 2016

Abstract deadlines: January 13, 2016

GMPV – Geochemistry, Mineralogy, Petrology & Volcanology

GMPV5 – Magmatic and volcanic processes

GMPV5.2/NH2.7Magma ascent, degassing and eruptive dynamics: linking experiments, models and observations

Convener: Mattia de’ Michieli Vitturi | Co-Conveners: Andrea Di Muro , Mike Burton

GMPV6 – Volcano monitoring and recent eruptions

GMPV7 – Natural Hazards Produced by Volcanic Activity

BILAN FINANCIER STRAP (IPGP – 20 keuros)

7 keuros – MultiGaS set - 209,50 euros (Anémomètre)

-M2 Moune-Di Muro 2016 MultiGaS (mission à l’OVPF – logement)

5 keuros – petrological and geochemical analysesMission ADM Paris/Lyon– geochemical analyses: 2464,21

-300 euros (EPMA Camparis)-Analyses M1 Di Muro - Métrich (2016)

2 keuros – thermometry--

6 keuros – scientific publication and meetingsMission E.Kaminski – Toulouse 450 euros