Print this pageBasin Evolution and Geomorphology of Tertiary Deep-Water Depositional Systems, Krishna-Godavari (K-G) Offshore Basin, India
Ravi Bastia1, Neeraj Sinha1, Ven
Kolla2, and Ram Janma Singh1
1 Reliance Industries Limited,
Navi Mumbai, India
2 Consultant, Houston, TX
High-quality 3D and 2D seismic data, state-of-art visualization techniques, stratal amplitude and spectral decomposition slices and amplitude guided voxel seeded geobodies show strong influence of slope geomorphology and the locations of Godavari and Krishna river systems on the Cenozoic deep-water depositional patterns in Krishna-Godavari offshore basin along the east coast of India. Subsequent to the initial easterly tilt of the Peninsular India during Late Cretaceous, both the rivers developed easterly drainage. Canyon cuts in Paleocene and Pliocene and their fill patterns suggest point sources to deep-water depositional systems. The canyons often exhibit a vertical relief of more than 100m. They were later back-filled by channelforms, which contain excellent reservoir quality sands. The geometry and internal architecture of these canyons and channel forms were generally controlled by the basin-forming tectonic trends and the relief of the continental margin. But the mildly sinuous nature of a Paleocene canyon and its orientation across a basement high suggests that the basement topography did not always influence the depositional pattern. A major easterly tilt of the Peninsular India in general and the K-G offshore in particular during Oligo-lower Miocene changed the loci of deep-water depocenters. Younger Canyon systems were cut on the Mio-Pliocene shelf edges and were filled with several highly sinuous channels. These sinuous channels evolved through lateral migration and aggradation by cut and fill. The fill of these channels suggest episodic sand and mud rich debris flows, and, sand and mud rich turbidites. Less sinuous channels flowed on the higher gradient slopes outside the canyon.
AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005