This multi-basin project, led by the Directorate General of Hydrocarbons, aims to uncover untapped oil and gas reserves to reduce India’s heavy import dependence and strengthen long-term energy security.
India is preparing for one of its most ambitious offshore oil-and-gas exploration campaigns in recent years. Survey ships will soon crisscross thousands of kilometres across the Bay of Bengal, scanning deep beneath the seabed for hydrocarbons that could reshape the country’s energy future.
The Directorate General of Hydrocarbons has floated bids on 14 May for a massive geological survey covering the Bengal-Purnea, Mahanadi, Krishna-Godavari, Cauvery and Andaman offshore regions.
Technically described as “2D Broadband Marine Seismic & Gravity-Magnetic Data Acquisition, Processing and Interpretation,” the project is essentially a giant underground scan of the ocean floor to identify commercially viable reserves buried beneath millions of years of sediment and rock.
The scale of the exercise is unprecedented. The Bengal-Purnea and Mahanadi survey alone will cover 45,000 line kilometres, the Andaman Basin another 43,000, Krishna-Godavari 43,000, and Cauvery 30,000.
Together, the survey lines stretch into lakhs of kilometres and will take nearly two years to complete. Specialised survey vessels will tow cable-like instruments called streamers, which transmit sound waves into the seabed and record echoes from underground rock formations.
Scientists will process this data to create detailed subsurface images several kilometres below the ocean floor, identifying structures where oil and gas may be trapped.
The strategic importance of this project lies in India’s energy vulnerability. The country imports nearly 85 per cent of its crude oil and over half of its natural gas, leaving households and industries exposed to global price shocks and geopolitical crises.
Recent conflicts in West Asia and the US-Iran war have underscored these risks. Officials note that India’s eastern offshore regions remain vastly underexplored compared to western areas like Mumbai High, with deep water zones still geologically promising but inadequately mapped using modern seismic technology.
Each basin offers unique potential. The Bengal Offshore Basin contains sedimentary layers exceeding 10 kilometres in thickness, with hydrocarbon plays from the Eocene to Miocene periods. The Mahanadi Basin is seen as commercially promising, with deepwater reservoirs and biogenic gas systems.
The Andaman Basin is strategically significant, with geological similarities to producing fields in Myanmar and Indonesia, and government papers highlight Miocene-age gas discoveries. Gas hydrates—frozen methane deposits beneath the seabed—are also noted as a potential future energy source.
The Krishna-Godavari Basin, already central to India’s gas production, may still hold undiscovered reserves in deeper sections, while the Cauvery Basin, a proven petroliferous region, is believed to contain untapped Jurassic and deep offshore plays.
Beyond geology, the project carries a larger strategic message. With global energy politics volatile, India is seeking to secure every possible domestic source. Union Petroleum Minister Hardeep Singh Puri has confirmed that India will invest over USD 20 billion under the Samudra Manthan program for offshore data acquisition, building on USD 500 million already spent on seismic surveys in the past eight years. This push comes as domestic production declines due to ageing fields, making fresh discoveries essential for energy self-sufficiency.
By opening nearly one million square kilometres of previously restricted offshore “No-Go” areas in 2022 and expanding exploration under the Hydrocarbon Exploration and Licensing Policy, India is
signalling its intent to aggressively pursue frontier basins.
Stratigraphic drilling campaigns are planned in the Andaman, Mahanadi, Saurashtra and Bengal basins, with deep-sea wells to follow. If successful, these surveys could transform India’s energy landscape, reduce import dependence, and provide critical breathing room in times of global volatility.
News18
