Seismicity associated with the Sumatra-Andaman Islands earthquake of 26 December 2004

Dewey, J. W.; Choy, G.; Presgrave, B.; Sipkin, S.; Tarr, A. C.; Benz, H.; Earle, P.; Wald, D.

Abstract:

The U.S. Geological Survey/National Earthquake Information Center (USGS/ NEIC) had computed origins for 5000 earthquakes in the Sumatra-Andaman Islands region in the first 36 weeks after the Sumatra-Andaman Islands mainshock of 26 December 2004. The cataloging of earthquakes of mb (USGS) 5.1 and larger is essentially complete for the time period except for the first half-day following the 26 December mainshock, a period of about two hours following the Nias earthquake of 28 March 2005, and occasionally during the Andaman Sea swarm of 26-30 January 2005. Moderate and larger (mb ???5.5) aftershocks are absent from most of the deep interplate thrust faults of the segments of the Sumatra-Andaman Islands subduction zone on which the 26 December mainshock occurred, which probably reflects nearly complete release of elastic strain on the seismogenic interplate-thrust during the mainshock. An exceptional thrust-fault source offshore of Banda Aceh may represent a segment of the interplate thrust that was bypassed during the mainshock. The 26 December mainshock triggered a high level of aftershock activity near the axis of the Sunda trench and the leading edge of the overthrust Burma plate. Much near-trench activity is intraplate activity within the subducting plate, but some shallow-focus, near-trench, reverse-fault earthquakes may represent an unusual seismogenic release of interplate compressional stress near the tip of the overriding plate. The interplate-thrust Nias earthquake of 28 March 2005, in contrast to the 26 December aftershock sequence, was followed by many interplate-thrust aftershocks along the length of its inferred rupture zone.

Genre:

Article

ProdID:

70032768

Citation Author:

Dewey, J. W.; Choy, G.; Presgrave, B.; Sipkin, S.; Tarr, A. C.; Benz, H.; Earle, P.; Wald, D.

Citation Contributing Office:

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

Citation Issue:

1 A SUPPL.

Citation Keywords:

Citation Language:

English

Citation Larger Work Title:

Bulletin of the Seismological Society of America

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

Citation Projection:

Citation Public Comments:

Citation Publisher:

Citation Series:

Citation Series Code:

Citation Series Number:

Citation Search Results Text:

Seismicity associated with the Sumatra-Andaman Islands earthquake of 26 December 2004; 2007; Article; Journal; Bulletin of the Seismological Society of America; Dewey, J. W.; Choy, G.; Presgrave, B.; Sipkin, S.; Tarr, A. C.; Benz, H.; Earle, P.; Wald, D.