Kerry Sieh TO Annual Meeting 8 November 2006

Kerry Sieh

TO Annual Meeting8 November 2006

Submerging forest on the Mentawai islands, West Sumatra

Behavior of the Sunda Megathrust Behavior of the Sunda Megathrust in Sumatrain Sumatra

Behavior of the Sunda Megathrust Behavior of the Sunda Megathrust in Sumatrain Sumatra

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 SuwargadiNughroho Hanato

Dudi PrayudiImam Suprihanto

Scripps Yehuda Bock et al

CollaboratorsCollaborators

Kyoto University Shigehiro Fujino

USC

Costas Synolakis

Jose Borrero

Segments that produce great earthquakes

Segments that are principally aseismic

Down-dip variations

1797

1833from Natawidjaja et al, JGR, 2006

Segments that produce great earthquakes

from Natawidjaja et al, JGR, 2006

1797

from Natawidjaja et al, JGR, 2006

1833

from Natawidjaja et al, JGR, 2006

1833

2004from Subarya et al., Science, 2006

2004from Chlieh et al,

BSSA, in press

2005 from Briggs et al, Science, 2006

2005 from Briggs et al, Science, 2006

Down-dip variations

2005 afterslip

from Hsu et al, Science, 2006

1907 tsunami ?

from Natawidjaja et al, JGR, in press

An aseismic shallow rupture in about 1962 from paleogeodetic data

An aseismic shallow rupture in about 1962

from paleogeodetic data

Simeulue Saddle

Segments that are principally aseismic

from Briggs et al, 2006, Science

The Simeulue SaddleThe Simeulue Saddle

Misalignment of ridge crests

~ 60 km

from Briggs et al, 2006, Science

Why? The misalignment suggests a structural cause

from Briggs et al, 2006, Science

The Equatorial patch

Small emergences during four giant earthquakes

Large emergence during the Mw 7.7 1935 earthquake

from Natawidjaja, 2003, PhD

The Enggano patch

from Chlieh et al, in preparation

From Chlieh et al, in

preparation

The permanence

of patch behavior

How often does the Mentawai

patch rupture?

Are couplets like 1797 and 1833 typical?

Bulasat

Simanganya

Years (AD)

Elevation relative to m

odern sea level~1370 ~1600 1797 & 1833

Paleoseismic

records

Bulasat

Simanganya

Years (AD)

Elevation relative to modern sea level

~1370 ~1600 1797 & 1833

Time-predictable?

Toward the application of

basic science for human benefit

Tsunami modeling

Educational outreach

For more information, see Sieh 2006 Proc Royal Soc

10-m slip

Nias-Simeulue tsunario

20-m slip

Aceh-Andaman tsunario

Tsunami modeling

10-m slip

Padang

population ~800,000

10-m slip

Bengkulu

population ~350,000

QuickTime™ and aH.264 decompressor

are needed to see this picture.

Our new educational poster

for residents

of the Sumatran

and Mentawai

island coasts

Where do we go from here?

From Chlieh et al, in

preparation

From Chlieh et al, in

preparation

From Chlieh et al, in

preparation

From Chlieh et al, in

preparation