kerry sieh to annual meeting 13 november 2007 kerry sieh to annual meeting 13 november 2007 soft...
TRANSCRIPT
Kerry Sieh TO Annual Meeting13 November 2007
Kerry Sieh TO Annual Meeting13 November 2007Soft corals lifted about 10 cm during the September 2007 earthquakesSoft corals lifted about 10 cm during the September 2007 earthquakes
Behavior of the Sunda Megathrust in Behavior of the Sunda Megathrust in SumatraSumatra
Behavior of the Sunda Megathrust in Behavior of the Sunda Megathrust in SumatraSumatra
Caltech John Galetzka Mohamed Chlieh Don Helmberger JP Avouac Aron Meltzner Ozgun Konca Yaru Hsu Mark Simons Andrew Kositsky
Indonesian Institute of Sciences
Danny Natawidjaja Bambang Suwargadi
Dudi PrayudiImam Suprihanto
Scripps Yehuda Bock Paul Jameson Peng Fang Linette Prawirodirjo Kyoto University
Shigehiro Fujino
USC
Jose Borrero
Soft corals lifted about 10 cm during the September 2007 earthquakesSoft corals lifted about 10 cm during the September 2007 earthquakes
CollaboCollaboratorsratorsCollaboCollaboratorsrators
SponsorSponsorssSponsorSponsorss
To understand the behavior of a great active fault at time scales important to understanding the earthquake cycle.Through the millennia
Through the centuries
During large earthquakes
base modified from NASA World Wind/Blue Marble
from Rich Briggs, after Briggs et al 2006
Deformation over millennia
by Rich BriggsThe earthquake cycle
Nias-Simeulue sectionNias-Simeulue section
Mentawai sectionMentawai section
southern Aceh-Andaman section
southern Aceh-Andaman section
Deformation over centuries
Nias-Simeulue and southern Aceh-Nias-Simeulue and southern Aceh-Andaman sectionsAndaman sections
Fossil Microatolldeaths in 1861
Fossil Microatolldeaths in 1861
Fossil Microatolldeaths in 1843
Fossil Microatolldeaths in 1843
Fossil Microatolldeaths in ~1799
Fossil Microatolldeaths in ~1799
(tentative)(tentative)
Fossil Microatolldeaths in ~1440
Fossil Microatolldeaths in ~1440
Fossil Microatolldeaths in ~1390
Fossil Microatolldeaths in ~1390
Fossil Microatolldeaths in ~1327
Fossil Microatolldeaths in ~1327
from Aron Meltzner
The Mentawais
Bulasat
Years (AD)Elevation relative to modern
sea level
AD 1357±141797 & 1833
2007
Sawtooth curve of
paleoseismic eventsNot yet
published
Simanganya
Years (AD)
Elevation relative to modern
sea level
2007
1.8±0.1 m
1.5±0.3 m
1.4±0.2 m
0.15 m
~0.2 m?
Sawtooth curve of
paleoseismic eventsNot yet
published
Narrow trench-parallel graben on an islet
west of South Pagai island
Victims of uplift -- dead Portuguese Men-o-War
Southern tip of South Pagai island
from Briggs et al (2006)
Vertical deformation in the field
Mega island, 4˚S
Measurements
Minor emergence near northern end of uplift
Island at the western entrance to Sikakap strait
Field measurements
Map of field measurements
Not yet published
Map of contoured field measurements
Not yet published
Map of contoured field measurements
Not yet published
Map of contoured field measurements
Not yet published
L-band InSAR from the Japanese ALOR satellite
cGPS measurements
Sumatran GPS Array (SuGAr) as of Sept 13, 2007
proposed early 2008
from Ozgun Konca
Horizontal (black) and vertical (red)
Displacements during the Mw8.4 mainshock
from Peng Fang via Ozgun Konca
Map of cGPS displacements
Not yet published
Silabu
(SLBU)
15-sec
cGPS from Jeff Genrich
Strong-ground-motion from Chris
Stephens via Ken Hudnut
Mw 8.4
K2 data
Not yet
published
15-sec data
Not yet published
1-sec data
Not yet published
Comparison of K2 and cGPS velocity records at Silabu
Horizontal (black) and vertical (red)
Displacements during the Mw7.9 aftershock
from Peng Fang via Anthony Sladen
Map of SuGAR vectors
Not yet published
Silabu
(SLBU)
15-sec
1-sec
cGPS from Jeff Genrich
Strong-ground-motion from Chris
Stephens via Ken Hudnut
Mw 7.9 and 7.0 aftershocks
7.9
7.0
7.9
10 cm
10 min
10 cm
K2 data
Not yet
published
15-sec data
Not yet published
1-sec data
Not yet published
Pukarayat (PKRT)
cGPS from Jeff Genrich
Mw 7.9 and 7.0 aftershocks
15-sec
7.9 7.
0
7.9
15-sec data
Not yet published
1-sec data
Not yet published
Horizontal (black) and vertical (red)
Displacements during the Mw7.0 aftershock
from Peng Fang via Anthony Sladen
Map of SuGAR vectors
Not yet published
Mw8.4 inversions
cGPS and teleseismic
databy Ozgun Konca
Teleseismic data only Data = black Model horizontal
(red) and vertical (gray)
Analyses
Maps of inversions
Not yet published
Mw8.4 inversions
by Ozgun Konca Data = black Model horizontal (red) and vertical (gray)
cGPS with coral at Mega
Detail Map of inversions
Not yet published
by Ozgun Konca
Mw8.4 inversions
Model displacements
Horizontal
Vertical (m)
from cGPS data only
Maps of vertical deformation estimated
from inversion of SuGAR data
Not yet published
Joint seismic/cGPS inversion of the 7.9 aftershock
by Anthony Sladen
Data = black Model horizontal = red and vertical = gray
Maps of inversion
Not yet published
Joint seismic/cGPS inversion of the 7.9 aftershock
by Anthony Sladen
Maps of inversion
Not yet published
Tsunami field data
by Jose Borrero
Measurements of runup along
mainland coast
Not yet published
Combined source of mainshock and two aftershocks -- Mw8.45
Data = black Model horizontal = red Model vertical = grayby Anthony Sladen
Maps of slip from
inversion
Not yet published
from Jean-Philippe and Anthony
Calculated interferogram from combined model
Base map from Mohamed Chlieh
Comparison of 50-year coupling and September events
How do the Sept 2007 events fit in to the long-term picture?
Map
Not yet published
from Mohamed, Anthony and Jean-Philippe
Accumulated potential slip versus slip during 8.4 in September
Map comparing
slip in 2007 with slip deficit
since 1833 and 1797
Not yet published
1797 1833
Natawidjaja et al, JGR, 2006
1833 2007
Maps of 2007 uplift
Not yet published
Bulasat
Years (AD)Elevation relative to modern
sea level
1797 & 1833
2007
Sawtooth curve of
paleoseismic events
Not yet published
by Rich Briggs