Petroleum and Natural gas are the important source of energy which is much in demand to accelerate the economic development. It provides lubricants and raw materials for a number of chemical industries such as kerosene, diesel, petrol, aviation-fuel, synthetic rubber, synthetic-fibre, thermoplastic resins, benzene-methanol, polystyrene, acrylates, detergents, aromatics, gasoline, carbon-black, dyes, colours, food-colours, pigments, explosives, printing ink, film-photography, greases, cosmetics, paints, lubricant oils, paraffin, and wax. Crude oil is obtained mainly from the sedimentary rocks of marine origin. In India, crude oil is found in the sedimentary rocks of the Tertiary period.
Petroleum and Natural Gas basins in India
• The Upper Assam Basin
• The Western Bengal Basin
• The Western Himalayan Basin
• The Rajasthan Saurashtra-Kachchh Basin
• The Northern Gujarat Basin
• The Ganga Valley Basin
• The Coastal Tamil Nadu, Andhra & Kerala Basin
• The Andaman and Nicobar Coastal Basin
• Offshore of the Khambat, Bombay High & Bassein
Petroleum or mineral oil is the next major energy source in India after coal. It provides fuel for heat and lighting, lubricants for machinery and raw materials for a number of manufacturing industries. Petroleum refineries act as a “nodal industry” for synthetic textile, fertiliser and numerous chemical industries. Most of the petroleum occurrences in India are associated with anticlines and fault traps in the rock formations of the tertiary age. In regions of folding, anticlines or domes, it occurs where oil is trapped in the crest of the unfold. The oil bearing layer is a porous limestone or sandstone through which oil may flow. The oil is prevented from rising or sinking by intervening non-porous layers.
Natural gas is an important clean energy resource found in association with or without petroleum. It is used as a source of energy as well as an industrial raw material in the petro- chemical industry. Natural gas is considered an environment friendly fuel because of low carbon dioxide emissions and is, therefore, the fuel for the present century. Large reserves of natural gas have been discovered in the Krishna- Godavari basin. Along the west coast the reserves of the Mumbai High and allied fields are supplemented by finds in the Gulf of Cambay. Andaman and Nicobar islands are also important areas having large reserves of natural gas. The 1700 km long Hazira- Bijaipur -Jagdishpur cross country gas pipeline links Mumbai High and Bassien with the fertilizer, power and industrial complexes in western and northern India. This artery has provided an impetus to India’s gas production. The power and fertilizer industries are the key users of natural gas. Use of Compressed Natural Gas (CNG ) for vehicles to replace liquid fuels is gaining wide popularity in the country.
Crude-Oil Producing fields in India
• The Bombay High Oilfields: It is largest petroleum production oilfield contributing over 65 per cent of the total production of crude oil that lies about 176 km to the south-west of Bombay. It has about 35 million tonnes of crude oil and about 40,000 million cubic metres of natural gas.
• Bassein Oilfield: It is located in the south of Bombay High and has rich deposits of oil and natural gas.
• Aliabet Oilfield: It is located about 45 km to the south of Bhavnagar.
• Ankleshwar: It is situated in the district of Bharauch, it stretches over an area of about 30 sq km. The oil of this region belongs to the Eocene period which was started in 1961. It is rich in gasoline and kerosene. The crude oil from this region is sent to the Koyali petroleum refinery.
• Cambay-Luni Region: It is located to the west of Vadodara. It was started in 1958. The estimated reserves of crude-oil are over 30 million tonnes.
• The Ahmadabad-Kalol Region: It lies to the north of Gulf of Khambat (Cambay) around the city of Ahmadabad and extends up to Mehsana. Kalol, situated about 25 km to the north of Ahmadabad is an important oilfield of the region. It was started in 1961. It supplied crude oil mainly to the Koyali refinery.
• The Digboi Oilfield: It extended over an area of about 15 sq km; the Digboi oilfield is one of the oldest oil-fields of the country. This Oilfield belongs to the Eocene and Miocene periods. There are 85 oil wells in this region. Most of the oil is sent to the refinery of Digboi. Since 1959, the Digboi oilfields are worked by the Oil India Limited (OIL).
• The Naharkatiya Oilfield: This oil-field lies about 35 km to the south-west of Digboi. Oil production from the Naharkatiya oilfields was started in 1954. Crude oil from this region is supplied to the refineries of Noonamati, New Bongaigaon (Assam), and Barauni (Bihar).