Why in News?

• Recently, Cairn Oil & Gas has announced that it is partnering with a US-based firm to start shale exploration in the Lower Barmer Hill formation, Western Rajasthan.

What is shale oil? How does it differ from conventional crude oil?

• The key difference between shale oil and conventional crude is that the former, also called ‘tight oil’, is found in smaller batches, and deeper than conventional crude deposits. 
• Its extraction requires creation of fractures in oil and gas rich shale to release hydrocarbons through a process called hydraulic fracking.
• Russia and the US are among the largest shale oil producers in the world, with a surge in shale oil production in the US having played a key role in turning the country from an importer of crude to a net exporter in 2019. 

What are the prospects of shale oil exploration in India?

• Currently, there is no large-scale commercial production of shale oil and gas in India.
• As per the policy guidelines notified by Government of India (GoI) for exploration and exploitation of shale gas and oil in India by National Oil Companies (NOCs), ONGC has identified 50 nomination PML (Petroleum Mining Lease) blocks under Phase-I.
• The exploratory efforts so far have led to the discovery of 65 small-to-medium sized hydrocarbon fields with about 356 million tonnes (oil and oil equivalent gas) of initial in-place on-land reserves.

Reference:

1. https://indianexpress.com/article/explained/shale-oil-exploration-potential-explained-7630082/