India is stepping up its oil and gas exploration drive along the eastern offshore frontier following successive natural gas discoveries in the Andaman Sea.

The government has announced a comprehensive program to reprocess decades‑old seismic data and undertake fresh deep‑water surveys across several promising sedimentary basins.

This initiative is designed to unlock untapped hydrocarbon resources and reduce the country’s dependence on imported crude oil and natural gas.

The program will cover the Mahanadi, Bengal‑Purnea, Cauvery and Krishna‑Godavari basins. Global geophysical firms have been invited to reprocess legacy 2D and 3D marine seismic datasets using advanced imaging technologies.

These efforts will be followed by new broadband 3D seismic surveys under the Multi‑Client model, with the entire exercise expected to be completed over a 36‑month period.

By applying modern imaging techniques to older datasets, authorities hope to generate clearer subsurface images, identify overlooked geological structures and refine prospective drilling targets ahead of future licensing rounds.

Officials have explained that the exercise will create integrated seismic volumes for each basin, improve geological models and identify new play fairways and hydrocarbon leads. Newly acquired seismic data will also be incorporated into the interpretation process, ensuring that subsurface geology is continuously updated and better understood. This approach is expected to provide a more accurate picture of India’s offshore hydrocarbon potential.

The east coast has been chosen for focus because of its proven and prospective basins. The Mahanadi Basin, situated off the Odisha coast, is classified as a Category‑II basin with discovered hydrocarbons but limited commercial production.

It is considered geologically analogous to the prolific Bengal Offshore Basin and hosts multiple hydrocarbon plays ranging from the Pliocene to the Cretaceous period. Thick sedimentary sections extending beyond 8 km in depth and deep‑water reservoirs are viewed as offering significant exploration potential.

The Bengal‑Purnea Basin contains sedimentary sequences exceeding 10 km in thickness, largely deposited by the Ganga‑Brahmaputra river system.

Geological studies suggest the basin may host significant Miocene‑age hydrocarbon accumulations, while biogenic gas indications have already been reported. The adjoining Purnea sub‑basin is considered prospective for hydrocarbons trapped within Gondwana‑age formations, adding to the region’s promise.

The Cauvery Basin, extending offshore from Tamil Nadu into the Bay of Bengal and the Gulf of Mannar, is already a proven petroleum‑producing region. Officials believe sizeable resources may still remain undiscovered, particularly in deeper Jurassic syn‑rift plays, fractured basement reservoirs and offshore carbonate systems. Sedimentary thicknesses in parts of the basin reach nearly 8 km, with the deepest exploration targets located between 7,000 and 8,000 metres below the surface.

The Krishna‑Godavari Basin remains India’s most prolific east‑coast gas province and is central to the country’s energy ambitions. It hosts multiple producing gas fields and features a complex petroleum system comprising deep‑water turbidites, basin‑floor fans, fault‑controlled Mesozoic reservoirs and gas hydrate occurrences. Continued exploration in this basin is expected to yield further discoveries that could significantly bolster domestic gas supplies.

The adoption of the Multi‑Client model is expected to accelerate exploration activity. Under this framework, geophysical companies invest in data acquisition and later market the datasets to multiple energy firms.

This reduces the government’s upfront costs while making high‑quality geological information available to potential investors. The model has been widely used internationally to stimulate exploration in frontier basins and is now being applied to India’s east coast.

Taken together, these surveys represent one of India’s most ambitious recent efforts to upgrade subsurface intelligence across its eastern offshore basins. With energy demand continuing to rise and import dependence remaining high, New Delhi is betting that improved seismic imaging today could pave the way for the next generation of domestic oil and gas discoveries.

The initiative underscores India’s determination to strengthen its energy security by tapping into offshore resources that have long been considered under‑explored.