Context: An Indian private-sector firm and US-based oil field services firm have entered into a partnership to begin shale exploration in Rajasthan.
Shale Oil and Gas

• Tight 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.
• Shale Gas: Unlike conventional hydrocarbons that can be extracted from the permeable rocks easily, shale gas is trapped under low permeable rocks.

Formation of Shale oil

• Shale oil are formed from hydrocarbons that are trapped in shale rock which can be extracted for refining.
• The oil is extracted via horizontal drilling techniques and hydraulic fracturing.
• It gives access to the reservoir rock.
• High-pressure of water, sand, and chemicals are pumped to fracture the shale and release the oil.

Advantages of Shale oil

• There is flexibility in oil extraction.
• Oil can be stored in wells until oil prices rise.
• It increases productivity.
• It reduces oil and gas prices.

Disadvantages of Shale oil

• It uses a lot of natural resources that gives negative impact to the environment.
• The extraction process of shale oil is much more capital and labor intensive.
• It may cause earthquakes.
• It also affects drinking water.

Shale oil can be classified into three broad groups

• Terrestrial – Lipid rich organic matter
• Lacustrine – Organic matter from algae
• Marine –Organic matter derived from marine animals

Shale Oil and India

• Exploration of shale gas and oil in India is done by National Oil Companies (NOCs).

It has been initiated in 4 basins

• Cambay basin
• Krishna & Godavari Basin
• Cauvery Basin
• Assam and Assam Arakan (A&AA) Basins

Additional Information
Conventional and Unconventional Resources

• Conventional oil or gas comes from formations that are straightforward to extract product from.
• Extracting fossil fuels from these geological formations can be done with standard methods that can be used to economically remove the fuel from the deposit.
• Conventional resources tend to be easier and less expensive to produce simply because they require no specialized technologies and can utilize common methods.

Unconventional oil or gas resources are much more difficult to extract.

• Some of these resources are trapped in reservoirs with poor permeability and porosity, meaning that it is extremely difficult or impossible for oil or natural gas to flow through the pores and into a standard well.
• To be able to produce from these difficult reservoirs, specialized techniques and tools are used.