Offshore drilling is a mechanical process in which a well is drilled beneath the seabed. It is usually carried out to explore and subsequently extract oil found in rock formations beneath the seabed. Most commonly, the term is used to describe drilling activities on the continental shelf, although the term can also be applied to drilling in lakes, coastal waters, and inland seas.
Offshore drilling presents environmental challenges, both offshore and onshore, due to the hydrocarbons produced and materials used during the drilling operation. Controversies include, for example, the current debate over offshore drilling in the United States").[1].
There are many different types of facilities from which offshore drilling operations are carried out. These include bottom drilling platforms (jackup barges and swamp barges), combined drilling and production facilities, either floating or bottom platforms, and deepwater mobile offshore drilling units (MODUs), including semisubmersibles and drillships. These are capable of operating in water depths of up to 3,000 meters (9,842.5 feet). In shallower waters, mobile units are anchored to the seabed, but in deeper waters (greater than 1,500 meters (4,921.3 ft) "semisubmersibles" or drillships" are held at the required drilling location by dynamic positioning").
History
Around 1891, the first submerged oil wells were drilled from platforms built on stilts in the fresh waters of Grand Lake St. Marys in Ohio. The wells were developed by small local companies such as Bryson, Riley Oil, German-American and Banker's Oil.[2].
Around 1896, the first saltwater submerged oil wells were drilled in the part of the Summerland field lying beneath the Santa Barbara Channel in California. The wells were drilled from piers that extended from the land into the canal.[3][4].
Other notable early submerged drilling activities occurred on the Canadian side of Lake Erie in the 1900s and at Caddo Lake in Louisiana in the 1910s. Shortly thereafter, wells were drilled in tidal zones along the Gulf Coast of Texas and Louisiana. The Goose Creek oil field near Baytown, Texas, is one example. In the 1920s, drilling activities were conducted from concrete platforms on Lake Maracaibo in Venezuela.[5].
One of the oldest underwater wells is the Bibi Eibat well, which became operational in 1923 in Azerbaijan.[6] The well was located on an artificial island in a shallow portion of the Caspian Sea. In the early 1930s, Texas Co., later Texaco (now Chevron) developed the first mobile steel barges for drilling in the brackish coastal areas of the Gulf of Mexico.
Troll Platform A
Introduction
Offshore drilling is a mechanical process in which a well is drilled beneath the seabed. It is usually carried out to explore and subsequently extract oil found in rock formations beneath the seabed. Most commonly, the term is used to describe drilling activities on the continental shelf, although the term can also be applied to drilling in lakes, coastal waters, and inland seas.
Offshore drilling presents environmental challenges, both offshore and onshore, due to the hydrocarbons produced and materials used during the drilling operation. Controversies include, for example, the current debate over offshore drilling in the United States").[1].
There are many different types of facilities from which offshore drilling operations are carried out. These include bottom drilling platforms (jackup barges and swamp barges), combined drilling and production facilities, either floating or bottom platforms, and deepwater mobile offshore drilling units (MODUs), including semisubmersibles and drillships. These are capable of operating in water depths of up to 3,000 meters (9,842.5 feet). In shallower waters, mobile units are anchored to the seabed, but in deeper waters (greater than 1,500 meters (4,921.3 ft) "semisubmersibles" or drillships" are held at the required drilling location by dynamic positioning").
History
Around 1891, the first submerged oil wells were drilled from platforms built on stilts in the fresh waters of Grand Lake St. Marys in Ohio. The wells were developed by small local companies such as Bryson, Riley Oil, German-American and Banker's Oil.[2].
Around 1896, the first saltwater submerged oil wells were drilled in the part of the Summerland field lying beneath the Santa Barbara Channel in California. The wells were drilled from piers that extended from the land into the canal.[3][4].
Other notable early submerged drilling activities occurred on the Canadian side of Lake Erie in the 1900s and at Caddo Lake in Louisiana in the 1910s. Shortly thereafter, wells were drilled in tidal zones along the Gulf Coast of Texas and Louisiana. The Goose Creek oil field near Baytown, Texas, is one example. In the 1920s, drilling activities were conducted from concrete platforms on Lake Maracaibo in Venezuela.[5].
In 1937, Pure Oil (now Chevron) and its partner Superior Oil (now ExxonMobil) used a fixed platform to develop a 1-mile (1.6 km) field off the coast of Calcasieu Parish, Louisiana in 14 feet (4.3 m) of water.
In 1938, Humble Oil built a mile-long wooden railroad trestle into the sea at McFadden Beach in the Gulf of Mexico, placing a derrick at its end, which was later destroyed by a hurricane.[7].
In 1945, concerns about American control of its offshore oil reserves led President Harry Truman to issue an Executive Order unilaterally extending American territory to the edge of its continental shelf, a law that effectively ended the "freedom of the seas" regime of the 3-mile limit.)
In 1946, Magnolia Petroleum (now ExxonMobil) drilled an 18-mile (29.0 km) site offshore, erecting a platform in 18 feet (5.5 m) of water off St. Mary Parish, Louisiana.[9].
In early 1947, Superior Oil erected a drilling and production platform in 20 feet (6.1 m) of water about 18 miles (29.0 km) off Vermilion Parish, Louisiana. But it was Kerr-McGee Oil Industries (now Occidental Petroleum), as operator for partners Phillips Petroleum (ConocoPhillips) and Stanolind Oil & Gas (BP), that completed its historic Ship Shoal Block 32 well in October 1947, months before Superior discovered a field from its Vermilion platform further offshore. In any case, that made the Kerr-McGee well the first oil discovery drilled out of sight of land.[10].
When offshore drilling moved to deeper waters up to 30 meters (98.4 ft), fixed platform rigs were built, until demand for 100 ft (30.5 m) rigs up to 120 meters (393.7 ft) deep in the Gulf of Mexico was needed, the first jack-up rigs began to appear from specialist offshore drilling contractors, such as the forerunners of ENSCO International.[5].
The first semisubmersible resulted from an unexpected observation in 1961. Blue Water Drilling Company owned and operated the four-column submersible platform Blue Water No. 1 in the Gulf of Mexico for Shell Oil Company. As the pontoons were not buoyant enough to support the weight of the rig and its consumables, it was towed between locations in a draft midway between the top of the pontoons and the bottom of the deck. It was noted that the movements at this draft were very small, and Blue Water Drilling and Shell jointly decided to attempt to operate the rig in floating mode. The concept of a stable, anchored floating deepwater platform had been designed and tested in the 1920s by Edward Robert Armstrong for the purpose of operating aircraft with an invention known as the 'seadrome'. The first purpose-built Ocean Driller drilling semi-submersible was launched in 1963. Since then, many semi-submersibles have been designed specifically for the mobile marine fleet drilling industry.
The first offshore drillship was the CUSS 1 developed for the Mohole project to drill into the Earth's crust.[11].
As of June 2010, there were over 620 mobile offshore drilling rigs (Elevated rig, semi-subs, drillships, barges) available for service in the competitive rig fleet.[12].
One of the deepest shafts in the world is currently the Perdido in the Gulf of Mexico, floating in 2,438 meters of water. It is operated by Royal Dutch Shell and was built at a cost of $3 billion.[13] The deepest operating platform is the Petrobras America Cascade FPSO on the Walker Ridge 249 field in 2,600 meters of water.[14].
Main drilling fields
The most notable drilling fields include:.
• - The North Sea.
• - The Gulf of Mexico (offshore of Texas, Louisiana, Mississippi and Alabama).
• - California (in the Los Angeles Basin and the Santa Barbara Channel, part of the Ventura Basin).
• - The Caspian Sea (in particular, some important fields offshore Azerbaijan).
• - The Santos and Campos basins off the coast of Brazil.
• - Newfoundland and Nova Scotia (Atlantic Canada).
• - Various fields off West Africa, most notably west of Nigeria and Angola.
• - Offshore fields in Southeast Asia and Sakhalin, Russia.
• - The main offshore oil fields are located in the Persian Gulf, such as Safaniya, Manifa and Marjan, which belong to Saudi Arabia and are developed by Saudi Aramco.[15].
• - Fields in India (Mumbai High, KG Basin-East Coast Of India, Tapti Field, Gujarat, India).
• - the Taranaki basin in New Zealand.
• - The Kara Sea north of Siberia[16].
• - The Arctic Ocean off the coast of Alaska and the Territories[17].
Challenges
Offshore oil and gas production is more challenging than onshore facilities due to the remote and more hostile environment. Much of the innovation in the offshore oil sector is about overcoming these challenges, including the need to provide very large production facilities. Production and drilling facilities can be very large and a large investment, such as the Troll A Platform which is located at a depth of 300 meters.[18].
Another type of offshore platform can float with a mooring system to keep it in place. While a floating system may be lower cost in deeper water than a fixed platform, the dynamic nature of platforms presents many challenges for drilling and production facilities.
The ocean can add several thousand meters or more to the fluid column. The addition increases equivalent circulating density and bottomhole pressures in drilling wells, as well as the energy needed to lift produced fluids for separation on the platform.
The trend today is to carry out more of the production operations subsea, by separating the water from the oil and re-injecting it rather than pumping it to a platform, or flowing onto land, with no visible facilities above sea. Subsea facilities help exploit resources in increasingly deeper waters, places that had been inaccessible, and overcome the challenges posed by sea ice, such as in the Barents Sea. One such challenge in shallower environments is excavation of the seafloor by drifting ice characteristics (means to protect offshore facilities from ice action include seafloor burial).
Offshore manned installations also present logistical and human resources challenges. An offshore oil rig is a small community in itself with cafeteria, dormitories, administration and other support functions. In the North Sea, staff members are transported by helicopter for a two-week shift. They generally receive a higher salary than ground workers. Supplies and waste are transported by ship, and supply deliveries must be carefully planned because storage space on the platform is limited. Today, a great effort is being made to relocate as many personnel as possible to the ground, where management and technical experts are in contact with the platform via video conference. An onshore job is also more attractive to the aging workforce in the oil industry, at least in the Western world. These efforts, among others, are contained in the established term Operations Integration. The increased use of subsea facilities helps achieve the goal of keeping more workers on land. Subsea facilities are also easier to expand, with new separators or different modules for different types of oil, and are not limited by the fixed floor space of an overwater facility.
Effects on the environment
Offshore oil production involves environmental risks, particularly oil spills from oil tankers or pipelines transporting oil from the platform to onshore facilities, and from leaks and accidents on the platform.[19] It is also generated, which is water brought to the surface along with the oil and gas; It is usually very saline and may include dissolved or unseparated hydrocarbons.
• - Oil industry.
• - Oil.
• - Fossil fuel.
• - Hydrocarbon.
• - Oil platform.
• - Aquatic submersible.
• - Subsoil.
• - Oceanic relief.
• - Organization of Petroleum Exporting Countries.
• - Center for Biological Diversity v Dept of the Interior April 17, 2009 DC appeal decision halting Alaska's offshore oil leases.
• - IODP-USIO: Publications: Minutes of the Integrated Ocean Drilling Program.
• - "New oil from the deep ocean floor." Popular Science, October 1975, pp. 106-108.
[7] ↑ Morton, Michael Quentin (June 2016). «Beyond Sight of Land: A History of Oil Exploration in the Gulf of Mexico». GeoExpro 30 (3): 60-63. Consultado el 8 de noviembre de 2016.: https://www.academia.edu/25960555
One of the oldest underwater wells is the Bibi Eibat well, which became operational in 1923 in Azerbaijan.[6] The well was located on an artificial island in a shallow portion of the Caspian Sea. In the early 1930s, Texas Co., later Texaco (now Chevron) developed the first mobile steel barges for drilling in the brackish coastal areas of the Gulf of Mexico.
In 1937, Pure Oil (now Chevron) and its partner Superior Oil (now ExxonMobil) used a fixed platform to develop a 1-mile (1.6 km) field off the coast of Calcasieu Parish, Louisiana in 14 feet (4.3 m) of water.
In 1938, Humble Oil built a mile-long wooden railroad trestle into the sea at McFadden Beach in the Gulf of Mexico, placing a derrick at its end, which was later destroyed by a hurricane.[7].
In 1945, concerns about American control of its offshore oil reserves led President Harry Truman to issue an Executive Order unilaterally extending American territory to the edge of its continental shelf, a law that effectively ended the "freedom of the seas" regime of the 3-mile limit.)
In 1946, Magnolia Petroleum (now ExxonMobil) drilled an 18-mile (29.0 km) site offshore, erecting a platform in 18 feet (5.5 m) of water off St. Mary Parish, Louisiana.[9].
In early 1947, Superior Oil erected a drilling and production platform in 20 feet (6.1 m) of water about 18 miles (29.0 km) off Vermilion Parish, Louisiana. But it was Kerr-McGee Oil Industries (now Occidental Petroleum), as operator for partners Phillips Petroleum (ConocoPhillips) and Stanolind Oil & Gas (BP), that completed its historic Ship Shoal Block 32 well in October 1947, months before Superior discovered a field from its Vermilion platform further offshore. In any case, that made the Kerr-McGee well the first oil discovery drilled out of sight of land.[10].
When offshore drilling moved to deeper waters up to 30 meters (98.4 ft), fixed platform rigs were built, until demand for 100 ft (30.5 m) rigs up to 120 meters (393.7 ft) deep in the Gulf of Mexico was needed, the first jack-up rigs began to appear from specialist offshore drilling contractors, such as the forerunners of ENSCO International.[5].
The first semisubmersible resulted from an unexpected observation in 1961. Blue Water Drilling Company owned and operated the four-column submersible platform Blue Water No. 1 in the Gulf of Mexico for Shell Oil Company. As the pontoons were not buoyant enough to support the weight of the rig and its consumables, it was towed between locations in a draft midway between the top of the pontoons and the bottom of the deck. It was noted that the movements at this draft were very small, and Blue Water Drilling and Shell jointly decided to attempt to operate the rig in floating mode. The concept of a stable, anchored floating deepwater platform had been designed and tested in the 1920s by Edward Robert Armstrong for the purpose of operating aircraft with an invention known as the 'seadrome'. The first purpose-built Ocean Driller drilling semi-submersible was launched in 1963. Since then, many semi-submersibles have been designed specifically for the mobile marine fleet drilling industry.
The first offshore drillship was the CUSS 1 developed for the Mohole project to drill into the Earth's crust.[11].
As of June 2010, there were over 620 mobile offshore drilling rigs (Elevated rig, semi-subs, drillships, barges) available for service in the competitive rig fleet.[12].
One of the deepest shafts in the world is currently the Perdido in the Gulf of Mexico, floating in 2,438 meters of water. It is operated by Royal Dutch Shell and was built at a cost of $3 billion.[13] The deepest operating platform is the Petrobras America Cascade FPSO on the Walker Ridge 249 field in 2,600 meters of water.[14].
Main drilling fields
The most notable drilling fields include:.
• - The North Sea.
• - The Gulf of Mexico (offshore of Texas, Louisiana, Mississippi and Alabama).
• - California (in the Los Angeles Basin and the Santa Barbara Channel, part of the Ventura Basin).
• - The Caspian Sea (in particular, some important fields offshore Azerbaijan).
• - The Santos and Campos basins off the coast of Brazil.
• - Newfoundland and Nova Scotia (Atlantic Canada).
• - Various fields off West Africa, most notably west of Nigeria and Angola.
• - Offshore fields in Southeast Asia and Sakhalin, Russia.
• - The main offshore oil fields are located in the Persian Gulf, such as Safaniya, Manifa and Marjan, which belong to Saudi Arabia and are developed by Saudi Aramco.[15].
• - Fields in India (Mumbai High, KG Basin-East Coast Of India, Tapti Field, Gujarat, India).
• - the Taranaki basin in New Zealand.
• - The Kara Sea north of Siberia[16].
• - The Arctic Ocean off the coast of Alaska and the Territories[17].
Challenges
Offshore oil and gas production is more challenging than onshore facilities due to the remote and more hostile environment. Much of the innovation in the offshore oil sector is about overcoming these challenges, including the need to provide very large production facilities. Production and drilling facilities can be very large and a large investment, such as the Troll A Platform which is located at a depth of 300 meters.[18].
Another type of offshore platform can float with a mooring system to keep it in place. While a floating system may be lower cost in deeper water than a fixed platform, the dynamic nature of platforms presents many challenges for drilling and production facilities.
The ocean can add several thousand meters or more to the fluid column. The addition increases equivalent circulating density and bottomhole pressures in drilling wells, as well as the energy needed to lift produced fluids for separation on the platform.
The trend today is to carry out more of the production operations subsea, by separating the water from the oil and re-injecting it rather than pumping it to a platform, or flowing onto land, with no visible facilities above sea. Subsea facilities help exploit resources in increasingly deeper waters, places that had been inaccessible, and overcome the challenges posed by sea ice, such as in the Barents Sea. One such challenge in shallower environments is excavation of the seafloor by drifting ice characteristics (means to protect offshore facilities from ice action include seafloor burial).
Offshore manned installations also present logistical and human resources challenges. An offshore oil rig is a small community in itself with cafeteria, dormitories, administration and other support functions. In the North Sea, staff members are transported by helicopter for a two-week shift. They generally receive a higher salary than ground workers. Supplies and waste are transported by ship, and supply deliveries must be carefully planned because storage space on the platform is limited. Today, a great effort is being made to relocate as many personnel as possible to the ground, where management and technical experts are in contact with the platform via video conference. An onshore job is also more attractive to the aging workforce in the oil industry, at least in the Western world. These efforts, among others, are contained in the established term Operations Integration. The increased use of subsea facilities helps achieve the goal of keeping more workers on land. Subsea facilities are also easier to expand, with new separators or different modules for different types of oil, and are not limited by the fixed floor space of an overwater facility.
Effects on the environment
Offshore oil production involves environmental risks, particularly oil spills from oil tankers or pipelines transporting oil from the platform to onshore facilities, and from leaks and accidents on the platform.[19] It is also generated, which is water brought to the surface along with the oil and gas; It is usually very saline and may include dissolved or unseparated hydrocarbons.
• - Oil industry.
• - Oil.
• - Fossil fuel.
• - Hydrocarbon.
• - Oil platform.
• - Aquatic submersible.
• - Subsoil.
• - Oceanic relief.
• - Organization of Petroleum Exporting Countries.
• - Center for Biological Diversity v Dept of the Interior April 17, 2009 DC appeal decision halting Alaska's offshore oil leases.
• - IODP-USIO: Publications: Minutes of the Integrated Ocean Drilling Program.
• - "New oil from the deep ocean floor." Popular Science, October 1975, pp. 106-108.
[7] ↑ Morton, Michael Quentin (June 2016). «Beyond Sight of Land: A History of Oil Exploration in the Gulf of Mexico». GeoExpro 30 (3): 60-63. Consultado el 8 de noviembre de 2016.: https://www.academia.edu/25960555