Tectonic Framework of Indian Eastern and Western Petroliferous Basins: A Synthesis

Virmani, Nancy ¹; Singh, Birendra P.¹
(1) Center for Petroleum & Applied Geology, Panjab University, Chandigarh, India.

Tectonic framework of east and west coast of Indian petroliferous basins are studied. The Krishna Godavari Basin, a typical passive margin basin, has a polycyclic (dual-rift province) evolution history. Till early Jurassic, the north eastern part indicate intracratonic rift set up and in late Jurassic to early Cretaceous syn-rift sediments were deposited due to tectonic subsidence accentuated by basement rifted fault system. The Cauvery Basin evolved in late Cretaceous due to rift-drift of the Indian plate from the Gondwanaland. The Bombay offshore Basin (passive margin Basin)has five mega tectonic elements; i.e. eastern homocline, graben system, central ridge system, shelf margin depression and west margin basement arch. The Cambay Basin is a linear NNW-SSE trending rift graben filled with more than 7 km of sediments overlying the deccan trap and evolved by three stages: syn rift (extensional, Palaeocene-early Eocene), post rift stage 1 (thermal subsidence, middle Eocene-early Miocene) and post rift stage 2 (structural inversion, middle Miocene- Recent). The Narmada Basin (pericratonic basin) formed due to reactivation of primordial faults in late Cretaceous along the Satpura trend and directly related to breakage of Gondwanaland and northward drifts of Indian plate. The Kutch- Saurashtra Basin (marginal rift basin) is formed along ENE-WSW trending faults by rifting in northern part and was connected to Tethys Sea in the north. The Assam-Arakan Basin is differentiated into northeasterly plunging linear ridges and depressions to the north of the Dauki-Naga faults and oriented in NE-SW directions and consists of long tight anticlinal folds and comparatively wide synclines. The Andaman-Nicobar Island is evolved through polyphasic, multigenetic tectonic events from early Cenozoic to Recent and basin has received sediments from Irrawadi delta-fan system in the north. The Bengal Basin forms as a part of Bengal fore-deep province and initiated as an intra-cratonic rift basin within Gondwanaland during late Palaeozoic to middle Mesozoic. Mahanadi Basin (passive margin basins) in east coast India is a classical arcuate type delta originated during late Mesozoic as a result of rifting and drifting of Indian plate from Antarctica and Australia.

AAPG Search and Discovery Article #90135©2011 AAPG International Conference and Exhibition, Milan, Italy, 23-26 October 2011.