State-run oil explorers ONGC and Oil India Ltd are planning to begin a ₹3,200 crore stratigraphic drilling campaign in untapped offshore areas early next year, as part of efforts to discover new hydrocarbon reserves and cut reliance on imports, officials said.
In the first phase, four wells will be drilled in deepsea of Andaman, Mahanadi, Saurashtra and Bengal sedimentary basins.
Global energy giant BP will provide technical expertise in identifying the locations as well as drilling, officials said. Stratigraphic drilling – also known as a stratigraphic test well – is a type of exploratory drilling aimed at studying underground geological formations rather than producing oil or gas. These wells are drilled to gather data on subsurface layers through continuous coring, petrophysical logging, and seismic data integration. The objective is to build a detailed geological profile to support future hydrocarbon exploration, without any immediate intent to extract resources. This will help reach a decision if the area holds hydrocarbon resources that could be commercially produced.
“ONGC has stated that they have a rig and we hope to start drilling sometime in early 2026,” an official involved in the process said. The government has agreed to compensate Oil and Natural Gas Corporation (ONGC) and Oil India (OIL) for the cost of the stratigraphic drilling campaign. The ₹3,200 crore estimated cost also includes a fee to be paid to BP for its services, officials said.
“The blocks (or areas) where the stratigraphic drilling is to take place is currently owned by the government and it alone will decide how any discovery has to be monetised – either through auctioning the area or giving it to a company or a consortium on a nomination basis,” another official said.
It is unclear if BP would like to be part of the monetisation. “It is entirely possible that they demand a first right of refusal (ROFR) in any development – getting a predefined percentage of stake in any consortium that monetises a discovery. But nothing has been conveyed so far,” the official said.
