Petroleum

• Crude petroleum is a mixture of hydrocarbons, including solids, liquids, and gases
• Compounds in petroleum include paraffin and unsaturated hydrocarbons, as well as a small proportion of benzene group compounds
• Petroleum and petroleum products are mainly used as motive power for transportation on land, in the air, and on water
• Petroleum is a convenient and compact liquid fuel that can be easily transported by tankers or pipelines
• Petroleum emits little smoke and leaves no ash, making it a cleaner fuel than coal
• It can be used up to the last drop and is an important source of lubricating agents
• Petroleum is also used as a raw material for various petrochemical products.

Origin and Occurrence

• Petroleum has an organic origin and is found in sedimentary basins and shallow depressions
• Oil reserves in India are associated with anticlines and fault traps in sedimentary rock formations of tertiary times
• Recent sediment also shows evidence of incipient oil
• An oil reservoir must have porosity, permeability, and be capped by impervious beds
• Porous sandstone, conglomerates, and fissured limestone containing oil should be capped by impervious beds
• Petroleum is mainly found in Miocene rocks (e.g. Mumbai High) and mid-folding rocks
• Petroleum and its products are used as a compact and convenient liquid fuel for transportation on land, air, and water
• It emits very little smoke and leaves no ash
• It provides the most important lubricating agents and is used as a raw material for various petrochemical products

Oilfields in India

• North-eastern India:
  • Major oilfields in Brahmaputra valley and neighboring areas including Arunachal Pradesh, Nagaland, Tripura, Manipur, Mizoram, and Meghalaya
  • Assam is the oldest oil-producing state in India
  • Digboi is the oldest oil field in India; most oil is sent to the refinery at Digboi
  • Naharkatiya field discovered in 1953; oil sent to oil refineries at Noonamati in Assam and Barauni in Bihar through pipeline
  • Oil reserves found in Manabhaum, Kharsang, and Charai in Arunachal Pradesh
  • Oil reserves found at Manmumbhanga, Manu, and Ampi Bazar in Tripura
• Western India Onshore field:
  • Oil fields found around the Gulf of Khambat in Gujarat
  • Main oil belt extends from Surat to Amreli; main producing districts include Kachchh, Vadodara, Bharuch, Surat, Ahmedabad, Kheda, and Mehsana
  • Important oilfields include Ankleshwar, Lunej, Kalol, Nawgam, Kosamba, Kathana, Barkol, Mehsana, and Sanand
  • Ankleshwar field is about 80 km south of Vadodara; capacity of 2.8 million tonnes per annum; oil sent to refineries at Trombay and Koyali
  • Khambhat or Lunej field drilled in 1958; annual production of 15 lakh tonnes of oil and 8-10 lakh cubic metres of gas; total reserves estimated at 3 crore tonnes
  • Ahmedabad and Kalol field contains ‘pools’ of heavy crude trapped in chunks of coal
• Rajasthan:
  • One of the largest on-land oil discoveries made in the Banner district of Rajasthan in 2004
  • Two important discoveries, Sarswati and Rajeshwari, with a total of 35 million tonnes of in-place oil reserves were made earlier in 2002
• Western Coast Off-Shore Oilfields:
  • Mumbai High is located on the continental shelf off the coast of Maharashtra; estimated reserves of about 330 million tonnes of oil and 37,000 million cubic metres of natural gas
  • Production on a commercial scale began in 1976; production declined between 1989-90 and 1993-94 due to overexploitation
  • Bassein is located to the south of Mumbai High; reserves may be higher than those of Mumbai High
  • Aliabet is located at Aliabet Island in the Gulf of Khambhat; huge reserves found in this field
• East Coast:
  • The basin and delta regions of the Godavari, the Krishna, and the Cauvery rivers hold great potential for oil and gas production, both onshore and offshore
  • Narimanam and Kovilappal oilfields in the Cauvery on-shore basin in Tamil Nadu expected to produce about 4 lakh tonnes of crude oil annually
  • Oilfields recently discovered in the Krishna-Godavari basin in Andhra Pradesh, which produces less than one percent of the total crude oil of India
• Probable Areas:
  • Vast possibilities of finding oil from about one lakh sq km area of sedimentary rocks in different parts of the country
  • Outstanding areas which hold possibilities of oil include Jawalamukhi, Nurpur, Dharamsala, and Bilaspur in Himachal Pradesh; Ludhiana, Hoshiarpur, and Dasua in Punjab; the Gulf of Mannar off the Tirun

Petroleum Refining

• India’s first oil refinery started in 1901 at Digboi in Assam
• Another refinery was built in 1954 at Tarapur in Mumbai
• India has a refinery hub with excess refining capacity, leading to exports of refined oil and petroleum products
• Oil is transported to refineries through pipelines
• Advantages of pipelines:
  • Ideal for transporting liquids and gases
  • Can be laid through difficult terrains and underwater
  • Requires little maintenance
  • Safe, accident-free, and environmentally friendly
• Disadvantages of pipelines:
  • Not flexible, can only be used for a few fixed points
  • Capacity cannot be increased once laid
  • Difficult to make security arrangements
  • Detection of leaks and repairs are also difficult
• Crude Oil Pipelines
  • Salaya-Mathura Pipeline (SMPL)
  • Paradip-Haldia-Barauni Pipeline (PHBPL)
  • Mundra-Panipat Pipeline (MPPL)
• Petroleum Product Pipelines
  • Guwahati-Siliguri Pipeline (GSPL)
  • Koyali-Ahmedabad Pipeline (KAPL)
  • Barauni-Kanpur Pipeline (BKPL)
  • Panipat-Delhi Pipeline (PDPL)
  • Panipat-Rewari Pipeline (PRPL)
  • Chennai – Trichy – Madurai Product Pipeline (CTMPL)
  • Chennai-Bangalore Pipeline
  • Naharkatia-Nunmati-Barauni Pipeline (first pipeline constructed in India)
  • Mumbai High-Mumbai-Ankleshwar-Koyali Pipeline.
  • Hajira-Bijapur-Jagdishpur (HBJ) Gas Pipeline
  • Jamnagar-Loni LPG Pipeline
  • Kochi-Mangalore-Bangalore pipeline
  • Vishakhapatnam Secunderabad pipeline
  • Mangalore-Chennai pipeline
  • Vijayawada-Vishakhapatnam pipeline

Strategic Petroleum Reserves

• Strategic petroleum reserves are stockpiles of crude oil to deal with oil-related crises.
• IEA countries must hold emergency oil stocks equivalent to at least 90 days of net oil imports.
• IEA members may decide to release these stocks to the market in case of severe oil supply disruption.
• India became an associate member of the IEA in 2017.
• India’s strategic crude oil storage facilities are located in Visakhapatnam, Mangaluru, and Padur.
• Two additional facilities have been approved for Chandikhol and Padur.
• The concept of dedicated strategic reserves was first mooted in the US after the OPEC oil crisis in 1973.
• Underground storage is the most economic method of storing petroleum products.
• The construction of the Strategic Crude Oil Storage facilities in India is being managed by ISPRL.
• ISPRL is a wholly-owned subsidiary of the Oil Industry Development Board (OIDB) under the Ministry of Petroleum & Natural Gas.

List of Major Oil Fields in India (with few details)

• DIGBOI:
  • Located in the Dibrugarh district of Assam.
  • Oldest oilfield in India with over 800 oil wells drilled.
  • Most of the oil is sent to an oil refinery at Digboi.
• NAHARKATIA:
  • Located 32 km southwest of Digboi at the left bank of Burhi Dihing river.
  • 60 wells drilled, out of which 56 produce natural gas.
  • Oil is sent to Noonmati (Assam) and Barauni (Bihar).
• MORAN-HUGRIJAN:
  • Located about 40 km southwest of Naharkatiya.
  • Discovered in 1953 and started production in 1956.
  • 20 wells drilled, yielding both oil and gas.
• RUDRASAGAR:
  • Located in the Upper Assam Valley.
  • Discovered by ONGC and OIL in 1961.
  • Oil deposits found in the Barail rocks.
• SIVSAGAR:
  • Located in the Upper Assam Valley on the bank of the Brahmaputra.
  • Once the capital of the Ahom rulers.
  • Oilfields located at Lakwa, Lakhmani, Rudrasagar, Geleki, and Moran.
• ANKALESHWAR:
  • Located 80 km south of Vadodara in Gujarat, discovered in 1958.
  • Ankleshwar anticline is about 20km long and 4 km wide.
  • Pandit Nehru called it “the Fountain of Prosperity.”
  • Oil is sent to Trombay and Kalol refineries.
• KALOL:
  • 25 km north of Ahmedabad
  • ‘pools’ of heavy crude trapped in coal at 1400 m depth
  • Oil production started in 1961
• NAWGAM:
  • 24 km south of Ahmedabad
  • Yields both oil and gas
• MEHSANA:
  • North of Ahmedabad
  • Famous for milk production and petroleum
  • Established in 1967
  • Highest onshore-producing asset of ONGC
• SANAND:
  • 16 km west of Ahmedabad
  • Produces both oil and gas
  • Tata Nano and Ford car plants located here
• LUNEZ:
  • Located 60 km west of Vadodara
  • First drilled in 1958 by ONGC
  • Produces both oil and gas
  • Estimated reserves – 30 million tonnes of oil
  • Oil – 15 lakh tonnes / year
  • Gas- 8-10 lakh cubic m/year
• KOSAMBA:
  • Located between Narmada and Tapi rivers in the Surat district of Gujarat
  • ONGC produces oil here
• KATHANA:
  • North Kathana is a 7 sq. km oil field located near Khambhat town in Gujarat
  • Oilfields are managed by the GSPC
• ALIABET:
  • Located in the Gulf of Khambhat on the Aliabet Island about 45 km off Bhavnagar
  • Huge reserves have been found
• BASSEIN:
  • Located to the south of the Mumbai High
  • Recently discovered which may prove to be higher than those of the Mumbai High
  • Production has already been started
• MUMBAI HIGH:
  • Located 176 km north-west of Mumbai on the continental shelf
  • Reserves – 330 million tonnes of oil and 37,000 million cubic meters of natural gas
  • Sagar Samrat- specially designed platform for oil extraction
  • Produces about two-third crude oil of India
• RAWA:
  • Located in Krishna – Godawari off–shore basin
  • Expected to produce 1 to 3 million tonnes of crude oil annually
  • Developed by Cairn India in partnership with ONGC, Videocon and Rawa Oil
  • Produces both oil and gas
• K-G BASIN:
  • The basin and delta of Krishna and Godavari hold great potential of oil and gas
  • Rawa field, Reliance’s gas field
  • Extensive exploration work is going on in the region
• NARIMANAM AND KOVILAPPAL:
  • Located in the Cauvery on–shore basin
  • Expected to produce about 4 lakh tonnes of crude oil annually
  • Oil will be refined at the Panaigudi refinery near Chennai
• MANGLA:
  • Major oilfields located in Rajasthan in the Barmer district
  • Consists of over 16 separate oil and gas fields of which the major three are Mangla, Bhagyam and Aishwarya
  • The current operator of the fields is Cairn India.