The west Andaman fault and its influence on the aftershock pattern of the recent megathrust earthquakes in the Andaman‐Sumatra region

Geophysical Research Letters - Tập 34 Số 3 - 2007
K. A. Kamesh Raju1, G.P.S. Murty2, Dileep Amarnath1, M. L. Mohan Kumar1
1National Institute of Oceanography, Goa, India
2Regional Center, National Institute of Oceanography, Visakhapatnam, India

Tóm tắt

Distinctly different rupture patterns of December 2004 and March 2005 megathrust earthquakes occurred in the Andaman‐Sumatra region suggest strong influence of tectonic and structural elements. We have analysed the shipboard gravity, bathymetry and seismic data across the West Andaman Fault (WAF), a major tectonic feature in the Andaman Sea, to infer the crustal structure and to examine its influence in controlling the aftershock pattern. Our results support the idea of Singh et al. (2005) that WAF forms a lithospheric scale boundary and together with other tectonic elements modulate the occurrence of large earthquakes and their rupture pattern. The active strike‐slip motion along the WAF, presence of backarc spreading coupled with increased obliquity of subduction in the Andaman Sector reduce the probability of occurrence of major or great earthquakes north of 10°N.

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Tài liệu tham khảo

10.1126/science.1112260

10.1016/j.jseaes.2004.09.001

Curray J. R., 1979, Tectonics of the Andaman Sea and Burma, Am. Assoc. Pet. Geol. Mem., 29, 189

10.1023/A:1023520105384

10.1130/0091-7613(1992)020<0259:MFZOSA>2.3.CO;2

10.1016/S0264-3707(03)00062-0

10.1016/j.epsl.2005.11.051

10.1016/S0012-821X(04)00075-5

10.1046/j.0956-540x.2001.01547.x

10.1126/science.1112250

10.1007/BF00309973

10.1126/science.1118950

10.1016/j.margeo.2004.05.001

10.1029/1999GL005396

Rudolfo K. S., 1969, Bathymetry and marine geology of the Andaman basin and tectonic implications for SE Asia, Am. Assoc. Pet. Geol. Bull., 52, 2422

10.1016/0040-1951(83)90097-5

10.1029/95JB01869

10.1016/0040-1951(88)90259-4

10.1029/2000JB900120

10.1029/2005EO480002

10.1038/434581a

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Geophysical Research Letters

Tập 34 Số 3

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