Late Cenozoic seismic stratigraphy of the Andaman Forearc Basin, Indian Ocean

Interpretation of new multichannel seismicreflection data from the Andaman Forearc Basin （AFB） inthe northern Indian Ocean is presented here. The high-quality multichannel seismic data from the AndamanForearc region enable us to examine the seismic charactersand to demarcate seismic sequences bounded by distinctunconformities. Ages of marked seismic horizons havebeen calibrated with available litholog data from nearbyindustry boreholes. Seismic interpretation of new datashows that the AFB is filled with - 4.5-s-two way traveltime （TWT） thick Neogene to Recent sediments. The entirebasin assemblage exhibits two distinct major sequencespertaining to the Neogene and Quaternary times. A largepart of the basin is filled with intermittent mass transportdeposits （MTD）. We infer that the episodic uplift of theInvisible Bank, protuberance of the outerarc and regulardeformation through reactivation of preexisting normalfaults since the Pleistocene could be attributed as causalmechanisms for the MTDs. Strong bottom simulatingreflectors are identified in the Late Miocene and youngersediments of the outerarc and AFB at a depth of ~ 0.6 sTWT and correspond to the presence of gas hydrates in thisregion. Our interpretations have significant implications forgeodynamic as well as resource exploration in the AFB.