Page 32 - DGH_Annual_Report

32 INDIA'S HYDROCARBON OUTLOOK 2024-2025

2.1.5 BENGAL-PURNEA BASIN

Bengal-Purnea is a Category III basin with largely undiscovered in-place, that calls for intense
exploration for a potential discovery.

The onland area geographically overlaps with the state(s) of Odisha, West Bengal. Purnea area
geographically overlaps with the state(s) of Bihar, West Bengal.

Source: DGH Internal
Source: DGH Internal

Bengal-Purnea is situated along the East This basin hosts a thick pile of sediments of 10,000
Coast of Indian peninsula and it has three sub- m and more, ranging from Permo-Triassic to
basins namely Bengal onland, Bengal offshore Recent. The basin’s onland part is mostly covered
and Purnea onland. The Bengal onland has by the Mesozoic sediments, overlain by the thick
established both oil and gas discoveries. Tertiary sediments comprising of Paleocene
to Recent sediments, mainly deposited by the
The offshore part of basin has two-third of Ganga-Brahmaputra river system.
potential lying in Middle Miocene play and
six gas discoveries are notified. Occurrence The hydrocarbon accumulations often indicate
of channelized deposits associated to subtle charging from in-situ shallower biogenic source
structures in the east-central area can be sequences. The establishment of thermogenic
significant exploration targets. plays (Mio-Pliocene) in recent discoveries in
Bengal onland (Asokenagar, 2019) point to
In the basin, some biogenic gas shows are potential deep-seated source rocks.
reported from the Tertiary stratigraphic interval
ranging from the oldest sediments of Paleogene Hinge zone of Bengal basin remains the
to the youngest sediments of Miocene-Pliocene exploration priority and the reservoir
complex, which are geographically distributed characterization studies of channel facies are the
majorly over offshore areas. thrust area.