Structural Characteristics of the Andaman Forearc Inferred from Interpretation of Multichannel Seismic Reflection Data

Acta Geologica Sinica - Tập 88 Số 4 - Trang 1145-1156 - 2014
Goli Anitha1, Dhananjai K. Pandey1
1National Centre for Antarctic and Ocean Research Vasco da Gama Goa‐403 804 India

Tóm tắt

AbstractThe Andaman Forearc Basin (AFB) is asymmetric in configuration and filled with a ∼6 km‐thick pile of Neogene to Recent sediments (∼4 s in two‐way travel time: TWT) with distinct zonation. It shows gradual thinning up to ∼3 km (0.8 s in TWT) towards the eastern end with a seabed gradient of 1:30. Thick deformed sediments ∼2 s (TWT) of the Outerarc are associated with intense faulting and occasional folding caused by recent tectonics. Development of a series of faults within the upwarped sedimentary column of Oligocene top to Recent is observed with a rotated fault block. These features are manifestations of Recent igneous intrusion, and reveal the presence of a mild N–S compressional regime. Its effect on the AFB resulted in further uplift of sediments, which can now be seen as the Invisible Bank. Forward gravity modelling supporting our seismic interpretation reveals that it is associated with igneous intrusion from the Moho (∼9 km depth), and also suggests that continental crust underlies the AFB. Strong Bottom Simulating Reflector (BSR)‐like features in the Miocene sediments of Outerarc and Forearc basin at a depth of 0.6 s below the seabed suggest the inferred probable occurrence of gas hydrates in the AFB.

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Tài liệu tham khảo

Bull J.M., 1990, Structural style of Intra-plate deformation, central Indian Ocean Basin: Evidence for the role of fracture zones, Tectonophysics, 25, 213228

Collett T.S., 2008, Directorate General of Hydrocarbons

10.1016/j.jseaes.2004.09.001

Curray J.R., 1979, Tectonics of the Andaman Sea and Burma, American Association of Petroleum Geolology. Memoir, 29, 189

10.1007/978-1-4615-8038-6_9

10.1016/0040-1951(93)90314-A

10.1023/A:1023520105384

10.1016/S0264-3707(03)00062-0

Hamilton W., 1979, Geological Survey Professional Paper 1078: 1 plate

10.1130/0016-7606(1988)100<1503:PTAIA>2.3.CO;2

10.1029/2000JB000095

10.1029/2002TC001420

Zhonghai Li, 2013, Dynamics of India-Asia Collision from 2-D and 3-D numerical modeling, Acta Geologica Sinica (English Edition), 87, 142

10.1016/j.tecto.2010.06.008

10.1306/111302730367

10.1016/j.tecto.2008.08.021

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

10.1029/2006GL028730

10.1029/1999GL005396

10.1130/0016-7606(1969)80[1203:BAMGOT]2.0.CO;2

Roy T.K., 1987, Wrench faulting in Andaman Forearc basin, India, Proceedings of the Offshore Technology Conference, 19, 393

10.1029/2000JB900120

10.1029/2005EO480002

10.1126/science.277.5334.1956

10.1016/j.epsl.2007.10.016

10.1016/S0743-9547(96)00068-2

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Acta Geologica Sinica

Tập 88 Số 4

1145-1156

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