From Assam’s Digboi to Rajasthan’s Thar: Can India’s oil-rich states power domestic demand?

India remains one of the world’s largest consumers of crude oil, yet domestic production is concentrated in a handful of states and basins. From the deserts of western India to the historic oilfields of the northeast, these regions hold the bulk of the country’s onshore reserves and form the backbone of India’s upstream energy sector.  

Government data shows that India’s total proven crude oil reserves stood at about 671 million tonnes in 2024, with the largest share located in the western offshore basin and major onshore reserves in Assam, Gujarat and Rajasthan.

Assam: One of India’s richest oil reserve regions  

Assam remains one of India’s most resource-rich oil states and the historic centre of the country’s petroleum industry. Oil was first discovered in Digboi in the late 19th century, making it one of Asia’s earliest oil-producing regions.  

The state holds around 153-155 million tonnes of crude oil reserves, accounting for roughly 26% of India’s onshore reserves, according to government energy statistics.  

Major oilfields include: Digboi, Naharkatiya, Moran  

These fields continue to supply crude oil to refineries across the country and support the northeastern energy economy.  

Gujarat: Western India’s major oil basin  

Gujarat is another major pillar of India’s onshore petroleum sector. The state hosts several mature oilfields in the Cambay Basin, which has been a key production area for decades. The state has around 115 million tonnes of crude oil reserves, representing nearly 20% of India’s reserves. 

Important oilfields include: Ankleshwar, Kalol, Gandhar  

Gujarat also houses some of India’s largest refineries, reinforcing its status as a major energy hub.  

Rajasthan: The rising oil producer  

Rajasthan has emerged as one of India’s fastest-growing oil-producing regions after major discoveries in the Barmer Basin during the 2000s. The state has around 34-35 million tonnes of crude oil reserves, accounting for roughly 6% of national reserves.

Key oilfields include: Mangala, Bhagyam, Aishwariya

Production from these fields transformed Rajasthan into one of India’s largest onshore crude oil producers.  

Tamil Nadu: Southern oil reserves in the Cauvery Basin  

Tamil Nadu contributes a smaller but significant share of India’s crude oil resources through the Cauvery Basin, which extends across parts of southern India and offshore areas. The state holds around 9 million tonnes of crude oil reserves, representing about 1.5% of national reserves.  

Smaller reserves also exist in other states

• Andhra Pradesh: About 7 million tonnes of crude oil reserves, mainly linked to the Krishna-Godavari basin.  
• Arunachal Pradesh: Around 3-4 million tonnes of reserves, mostly in small northeastern exploration blocks.  

Though these reserves are relatively modest, exploration activity continues as part of India’s strategy to boost domestic production.  

Offshore basins dominate India’s reserves  

Despite the importance of onshore states, India’s largest oil reserves lie offshore. The Western Offshore basin, which includes the famous Mumbai High fields, accounts for roughly 37-38% of the country’s crude oil reserves — the largest share among all regions.  

Why these reserves matter  

India imports more than 85-90% of the crude oil it consumes, making domestic reserves strategically important for energy security. Expanding exploration, improving recovery from mature fields, and developing new basins remain key priorities as India seeks to reduce its dependence on imported oil.

(The figures are based on a 2021 report by the Ministry of Statistics)