1IPGP - Institut de Physique du Globe de Paris (IPGP, 1 rue Jussieu, 75238 Paris cedex 05 ; Université Paris Diderot, Bât. Lamarck A case postale 7011, 75205 Paris CEDEX 13 - France)
Abstract : A new three-dimensional seismic model and relocated regional seismicity are used to illuminate the great Sumatra-Andaman Islands earthquake of December 26, 2004. The earthquake initiated where the incoming Indian Plate lithosphere is warmest and the dip of the Wadati-Benioff zone is least steep along the subduction zone extending from the Andaman Trench to the Java Trench. Anomalously high temperatures are observed in the supra-slab mantle wedge in the Andaman back-arc. The subducting slab is observed along the entire plate boundary to a depth of at least 200 km. These factors contribute to the location of the initiation of rupture, the strength of seismic coupling, the differential rupture properties between the northern and southern segments of the earthquake, and the cause of convergence in the Andaman segment.
https://hal-insu.archives-ouvertes.fr/insu-03603734 Contributor : Nathalie PothierConnect in order to contact the contributor Submitted on : Thursday, March 10, 2022 - 10:29:07 AM Last modification on : Saturday, March 12, 2022 - 3:32:31 AM
Nikolai M. Shapiro, Michael H. Ritzwoller, E. Robert Engdahl. Structural context of the great Sumatra-Andaman Islands earthquake. Geophysical Research Letters, American Geophysical Union, 2008, 35, ⟨10.1029/2008GL033381⟩. ⟨insu-03603734⟩