Oil on a industrial scale is often found the place the sedimentary rock strata are inclined and folded; in a type of chamber or reservoir, in the highest attainable scenario e.g. crests of anticlines. Normally, oil is related to water. Being lighter than water (particular gravity of zero.Eight to zero.98), it collects within the anticlines or fault traps above the floor of water. Gas remains to be lighter and occurs above oil. Thus on drilling an oil properly, one finds fuel adopted by oil, though fuel seepage is just not at all times a positive indication of an oil reservoir.
As already mentioned, oil as well as natural gas in India occur in sedimentary rocks. About 14.1 lakh sq km or about 42 per cent of the full space of the country is coated with sedimentary rocks out of which about 10 lakh sq km kind marine basins of Mesozoic and Tertiary instances.
In addition to, the nation has offshore areas having Mesozoic and Tertiary rocks of marine origin overlaying an space of two.5 lakh sq km upto a depth of one hundred metre and another area of zero.7 lakh sq km upto a depth between a hundred and 200 metre. Thus the entire continental shelf of probable oil bearing rocks quantities to 3.2 lakh sq km (see Fig. 26.4).
The total sedimentary area including each on shore and offshore includes 27 basins. The geological and geophysical studies have been performed in 14 basins whereas exploratory drilling has been carried out in 9 basins. Mumbai High, the Khambhat Gulf and the Assam are probably the most productive areas.
Though India has huge areas coated by sedimentary rocks, structures containing oil should not in proportion to the expanses of those rocks and are found in restricted situations. The Indian Mineral 12 months Ebook 1982 estimated a reserve of 468 million tonnes of which 328 million tonnes was available in Mumbai Excessive. In 1984 the reserves have been estimated at 500 million tonnes.
The Indian Petroleum and Pure Gasoline Statistics put the total reserves of crude oil at 581.43 million tonnes in 1986-87. The prognosticated hydrocarbon useful resource base in Indian sedimentary basins together with deep water has been estimated at about 28 billion tonnes.
Of this only about one-fourth i.e., 7.2 billion tonnes of in place hydrocarbon reserves have been established as on 1 April, 2002. About 70 per cent of the established hydrocarbon reserves is oil and relaxation is gasoline. The recoverable hydrocarbon reserves are of the order of 2.6 billion tonnes.
India was a very insignificant producer of petroleum at the time of Independence and remained so till Mumbai High started manufacturing on a large scale. In truth, off-shore manufacturing didn’t start till the mid 1970s and the entire manufacturing was obtained from on-shore oil fields.
In 1980-81 about half of the manufacturing of crude oil got here from on-shore fields whereas the remaining half was received from the off-shore resources. After that juncture, the off-shore production increased at a a lot quicker rate than the on-shore manufacturing. For greater than two decades from 1990-91 to 2003-04, about two-thirds of production of crude oil is provided by the off-shore fields.
The manufacturing touched the all time peak of 34.09 million tonnes in 1989-90 however slumped to 30.44 million tonnes in 1991-ninety two, 28.Forty six million tonnes in 1992-93 and further to 27.03 million tonnes in 1993-ninety four. Sharp drop of production by over 7 million tonnes in a brief span of 4 years is ascribed to overworking of Mumbai Excessive oil wells. This was a dangerous development and was to be reversed at all costs.
Quite a lot of brief term and medium term measures similar to early production from satellite tv for pc fields, use of state-of-the-art expertise i.e. horizontal drilling, drain gap drilling, and so forth. have been initiated in 1993. In consequence of these measures the production increased to 32.24 million tonnes in 1994-ninety five, 37.24 million tonnes in 1995-96 and to 38.57 million tonnes in 1996-97.
A second phase of falling manufacturing was noticed after 1996-ninety seven and the manufacturing stood at 31.9 million tonnes in 1999-2001. After 2001-02, a marginal enhance in manufacturing has been recorded. In 2003-04 India produced 33.Four million tonnes of crude oil out of which eleven.5 million tonnes got here from on-shore sources whereas about twice that amount, i.e., 21.9 million tonnes of oil was produced by off-shore oilfields.
India is obtained each from on-shore and off-shore areas, but off-shore areas made a serious contribution (see Desk 26.4 and 26.5)
Desk 26.Four Manufacturing of Petroleum (Crude) in India (Million tonnes):
Table 26.5 Manufacturing of Petroleum (Crude) in India, 2002-03:
Oil extracted from the oil wells is in its crude type and contains many impurities. It’s refined in oil refineries before use. After refining, various merchandise corresponding to kerosene, diesel, petrol, lubricants, bitumen, and wire mesh corrugated so on. are obtained. Though India’s first oil refinery started working way again in 1901 at Digboi in Assam, it remained the one refinery in the whole of India for greater than half a century.
It was solely in 1954 that one other refinery at Tarapur (Mumbai) joined the lone refinery of Digboi. Since then oil refining in India has progressed at a speedy pace. At the moment there are 19 refineries in the country, 17 in the public sector, one in joint sector and one in non-public sector. The installed refining capacity was solely zero.3 million tonnes in 1950-fifty one which rose to 121.Eight million metric tonnes in 2003-04.
Seventeen public sector refineries are located at Guwahati, Barauni, Koyali, Haldia, Mathura, Digboi, Panipat, Chennai, Narimanam, Bongaigaon, Mumbai (HPCL), Vishakhapatnam, Mumbai (BPCL), Kochi, Numaligarh, Tatipaka (ONGC) and Bina (M.P.) Bina refinery was inaugurated in June 2003. Aggregate refining capacity of those plants is seventy five.95 million tonnes per annum.
One refinery in joint sector is at Mangalore in Karnataka. It has refining capacity of 9.Sixty nine million tonnes per annum. Non-public sector refinery of Reliance Petroleum Limited was commissioned at Jamnagar in 2001. With an installed capability of 27 million tonnes, it is the biggest refinery in the nation. The prevailing and beneath development/proposed refineries are shown in Fig. 26.6.
Consumption of oil and its merchandise has all the time outstripped manufacturing in India. In 1950-51, India produced only 2.7 lakh tonnes of oil against consumption of 34 lakh tonnes. With the progress in industries and transport, want for oil has elevated dramatically in the publish-unbiased era. Consequently, India has to lean closely on the imports of oil and its merchandise.
It is obvious from Desk 26.6 that our oil bill has been rising somewhat disturbingly both when it comes to amount and worth attributable to our elevated calls for for economic progress and because of rising prices of oil and oil products in the international market. Our oil import bill increased from less than 9 per cent of the total imports in 1960s to 30 per cent following the first oil crisis in 1973-seventy four and to 75 per cent in 1980s after the second oil disaster.
Table 26.6 Imports of Petroleum, Oil and Lubricants:
Decline in indigenous manufacturing during 1989-90 and 1993-94 additional worsened the steadiness between production and consumption. Within the year 2003-04, India imported 99,495 thousand tonnes petroleum, oil and lubricants in opposition to the home production of 33,043 thousand tonnes solely. Thus our imports of oil have been greater than thrice the indigenous manufacturing.
This puts severe strain on our international alternate reserves. With improve in growth of industries and transport, demand for oil will enhance additional and make issues still worse. In 2003-04, our oil belt accounted for 28.7 per cent of the overall imports.