Please use this identifier to cite or link to this item:
Authors: Lorito, S.* 
Piatanesi, A.* 
Cannelli, V.* 
Romano, F.* 
Melini, D.* 
Title: Kinematics and Source Zone Properties of the 2004 Sumatra-Andaman Earthquake and Tsunami: Nonlinear Joint Inversion of Tide-Gage, Satellite Altimetry and GPS data
Issue Date: 2009
DOI: 10.1029/2008JB005974
Keywords: Source process
joint inversion
Subject Classification04. Solid Earth::04.06. Seismology::04.06.03. Earthquake source and dynamics 
Abstract: We (re)analyzed the source of the 26 December 2004 Sumatra-Andaman earthquake and tsunami through a nonlinear joint inversion of an in-homogeneous dataset made up of tide-gages, satellite altimetry, and far-field GPS recordings. The purpose is two-fold: (1) the retrieval of the main kinematics rupture parameters (slip, rake, rupture velocity); (2) the inference of the rigidity of the source zone. We independently estimate the slip from tsunami data and the seismic moment from geodetic data, so to derive the rigidity. Our results confirm that the source of the 2004 Sumatra-Andaman earthquake has a complex geometry, constituted by three main slip patches, with slip peaking at ~30 meters in the Southern part of the source. The rake direction rotates counter-clockwise at North, according to the direction of convergence along the trench. The rupture velocity is higher in the deeper than in the shallower part of the source, consistently with the expected increase of rigidity with depth. It is also lower in the Northern part, consistently with known variations of the incoming plate properties and shear velocity. Our model features a rigidity (20-30 GPa), that is lower than PREM average for the seismogenic volume [Dziewonski and Anderson, 1981]. The source rigidity is one of the factors controlling the tsunamigenesis: for a given seismic moment, the lower the rigidity, the higher the induced seafloor displacement. The general consistence between our source model and previous studies supports the effectiveness of our approach to the joint inversion of geodetic and tsunami data for the rigidity estimation.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
Lorito_JGR_2009_in_press.pdfpaper in press4.96 MBAdobe PDFView/Open
Show full item record

Page view(s)

Last Week
Last month
checked on Aug 21, 2018


checked on Aug 21, 2018

Google ScholarTM