Deepwater Horizon
Encyclopedia
Deepwater Horizon was an ultra-deepwater, dynamically positioned
, semi-submersible
offshore oil drilling rig
owned by Transocean
. Built in 2001 in South Korea by Hyundai Heavy Industries
, the rig was commissioned by R&B Falcon, which later became part of Transocean
, registered in Majuro
, Marshall Islands
, and leased to BP
from 2001 until September 2013. In September 2009, the rig drilled the deepest oil well
in history at a vertical depth of 35050 ft (10,683 m) and measured depth of 35055 ft (10,685 m) in the Tiber Oil Field at Keathley Canyon
block 102, approximately 250 miles (402.3 km) southeast of Houston, in 4132 feet (1,259.4 m) of water. On 20 April 2010, while drilling at the Macondo Prospect
, an explosion on the rig
caused by a blowout
killed 11 crewmen and ignited a fireball
visible from 35 miles (56.3 km) away. The resulting fire could not be extinguished and, on 22 April 2010, Deepwater Horizon sank, leaving the well gushing at the seabed
and causing the largest offshore oil spill
in U.S. history.
, column-stabilized, semi-submersible mobile offshore drilling unit
, designed to drill subsea
wells for oil exploration and production using an 18.75 in (476.3 mm), blowout preventer
, and a 21 in (533.4 mm) outside diameter marine riser.
Deepwater Horizon was the second semi-submersible rig constructed of a class of two, although Deepwater Nautilus
, its predecessor, is not dynamically positioned. The rig was 396 by and capable of operating in waters up to 8000 feet (2,438.4 m) deep, to a maximum drill depth of 30000 ft (9,144 m), and in 2010 was one of approximately 200 deepwater offshore rigs capable of drilling in waters more than 5000 ft (1,524 m). Its American Bureau of Shipping
(ABS) class notations were "A1, Column Stabilized Drilling Unit, AMS, ACCU, DPS-3".
In 2002, the rig was upgraded with "e-drill," a drill monitoring system whereby technical personnel based in Houston, Texas, received real-time
drilling data from the rig and transmitted maintenance and troubleshooting information.
Advanced systems played a key role in the rig's operation, from pressure and drill monitoring technology, to automated shutoff systems and modelling systems for cementing. The OptiCem cement modelling system, used by Halliburton in April 2010 for BP's Gulf of Mexico drill, played a crucial part in cement slurry mix and support decisions. These decisions have become a focus for investigations into the explosion on the rig that month.
) by Hyundai Heavy Industries
in Ulsan
, South Korea. Construction started in December 1998, the keel
was laid on 21 March 2000, and the rig was delivered on 23 February 2001, after the acquisition of R&B Falcon by Transocean.
Transocean, through its Steinhausen, Switzerland
subsidiary Triton Asset Leasing GmbH, operated the rig under the Marshalese
flag of convenience
. The rig was leased to BP on a 3 year contract for deployment in the Gulf of Mexico
following construction, the lease being renewed in 2004 for a year, 2005 for 5 years, and 2009 for a further 3 years covering 2010 - 2013. The latter contract was worth $544 million, or $496,800 per day for 3 years, for the "bare rig", with crew, gear and support vessels estimated to cost the same per day again.
According to R&B Falcon's SEC filings for 2001, the transfer document between R&B Falcon and Transocean was dated 17 August 2001, and the rig was specified as "official registration number of 29273-PEXT-1, IMO No. 8764597, with Gross Tonnage of 32,588 and with Net Tonnage of 9,778" and the transfer value as . As at 2010, the rig was insured for , the sum covering its replacement cost and wreckage removal.
(BP 56%, BHP Billiton
44%) and Thunder Horse (BP 75%, ExxonMobil
25%) oil field
s. It was described at times as a "lucky" and "celebrated" rig, and in 2007 was still described as "one of the most powerful rigs in the world". In 2006 it discovered oil in the Kaskida oil field
, and in 2009 the "giant" Tiber field. The well in the Tiber field has a vertical depth of 35050 ft (10,683 m) and a measured depth of 35055 ft (10,685 m), below 4132 ft (1,259.4 m) of water. The well was the deepest oil well in the world, and more than 5000 feet (1,524 m) further below the seabed than the rig's official drilling specification stated on the company's fleet list.
In February 2010, Deepwater Horizon commenced drilling an exploratory well at the Macondo Prospect (Mississippi Canyon
Block 252), about 41 miles (66 km) off the southeast coast of Louisiana
, at a water depth of approximately 5000 feet (1,524 m). The Macondo prospect exploration rights were acquired by BP in 2009, with the prospect jointly owned by BP (65%), Anadarko
(25%) and MOEX Offshore 2007
(10%). Deepwater Horizon was still working on the Macondo site on 20 April 2010, when a violent explosion occurred leading to destruction of the rig and resulting oil spill. The well was in the final stages of completion at the time; its cement casing was injected and hardening, and the rig was due to move shortly to its next role as a semi-permanent production platform at the Nile site following by a return to the Kaskida field. The exploratory work was described as "concluded" and permission had already been requested from MMS to terminate operations at the Macondo site.
During its operational lifetime, the rig was actively in operation for 93% of its working life (2,896 of 3,131 days). The remainder partly relates to time spent between sites.
(renamed on 18 June 2010 to the Bureau of Ocean Energy Management, Regulation and Enforcement, or Bureau of Ocean Energy (BOE)) is the regulatory and inspecting body for offshore oil drilling and rigs in the United States of America. According to an Associated Press
investigation, certain safety documentation and emergency procedure information, including documentation for the exact incident that later occurred, was absent. The exact number of required monthly inspections varied over time, with the required monthly inspection for the first 40 months but after that around 25% of inspections were omitted, although the investigation notes this is partly expected, since there are circumstances such as weather and movement which preclude an inspection. Reports of the last three inspection for 2010 were provided under Freedom of Information
laws. Each of these inspections had taken two hours or less.
During its lifetime the rig received 5 citations for non-compliance, 4 of which were in 2002 (safety, including the blowout preventer) and the other in 2003 (pollution). A sixth citation in 2007 related to non-grounded
electrical equipment was later withdrawn when the equipment was determined to be compliant with regulations. Overall the Deepwater Horizons safety record was "strong" according to a drilling consultant reviewing the information. In 2009 the Minerals Management Service "herald[ed] the Deepwater Horizon as an industry model for safety". According to AP's investigation "its record was so exemplary, according to MMS officials, that the rig was never on inspectors' informal 'watch list' for problem rigs".
gas, and water. The gas component of the slushy material quickly transitioned into a fully gaseous state and then ignited into a series of explosions and then a firestorm. An attempt was made to activate the blowout preventer
, but it failed.
At the time of the explosion, there were 126 crew on board; seven were employees of BP, 79 of Transocean, there were also employees of various other companies involved in the operation of the rig, including Anadarko
, Halliburton
and M-I SWACO. Eleven workers were presumed killed in the initial explosion. The rig was evacuated, with numerous injured workers airlifted to medical facilities. After burning for approximately 36 hours, Deepwater Horizon sank on 22 April 2010. The remains of the rig were located resting on the seafloor
approximately 5000 ft (1,524 m) deep at that location, and about 1300 ft (396.2 m) (quarter of a mile) northwest of the well.
The resultant oil spill
continued until July 15 when it was temporarily closed by a cap. Relief well
s were used to permanently seal the well, which was declared "effectively dead" on September 19, 2010.
s note that the insurance recovery is likely to outweigh the value of the rig (although not necessarily its replacement value) and any liabilities - the latter estimated at up to .
Litigation, ultimate roll call of damage, and the scope of final insurance recovery are all unknown , with analysts reporting that the aftermath is of unprecedented scale and complexity compared to previous disasters which themselves took many years to unfold and resolve. A July 2010 analysis by the Financial Times
on the aftermath cites legal sources as saying that "at some point the scale of the litigation
becomes so large that it really is novel", that "the situation is likely be complicated further because the variety of probable cases means it will be hard to aggregate them into so-called class action
s" and that there is "no way to put this in historical context because we have never faced anything like this before". As with the Exxon Valdez disaster, litigation is being discussed in terms of a 20 year timescale.
Dynamic positioning
Dynamic positioning is a computer controlled system to automatically maintain a vessel's position and heading by using its own propellers and thrusters...
, semi-submersible
Semi-submersible
A semi-submersible is a specialised marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes.The...
offshore oil drilling rig
Offshore drilling
Offshore drilling refers to a mechanical process where a wellbore is drilled through the seabed. It is typically carried out in order to explore for and subsequently produce hydrocarbons which lie in rock formations beneath the seabed...
owned by Transocean
Transocean
Transocean Ltd. is one of the world's largest offshore drilling contractors. The company rents floating mobile drill rigs, along with the equipment and personnel for operations, to oil and gas companies at an average daily rate of US$282,700...
. Built in 2001 in South Korea by Hyundai Heavy Industries
Hyundai Heavy Industries
Hyundai Heavy Industries Co., Ltd. is the world's largest shipbuilding company, headquartered in Ulsan, South Korea. The company is a subsidiary of Hyundai Heavy Industries Group...
, the rig was commissioned by R&B Falcon, which later became part of Transocean
Transocean
Transocean Ltd. is one of the world's largest offshore drilling contractors. The company rents floating mobile drill rigs, along with the equipment and personnel for operations, to oil and gas companies at an average daily rate of US$282,700...
, registered in Majuro
Majuro
Majuro , is a large coral atoll of 64 islands in the Pacific Ocean, and forms a legislative district of the Ratak Chain of the Marshall Islands. The atoll itself has a land area of and encloses a lagoon of...
, Marshall Islands
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
, and leased to BP
BP
BP p.l.c. is a global oil and gas company headquartered in London, United Kingdom. It is the third-largest energy company and fourth-largest company in the world measured by revenues and one of the six oil and gas "supermajors"...
from 2001 until September 2013. In September 2009, the rig drilled the deepest oil well
Oil well
An oil well is a general term for any boring through the earth's surface that is designed to find and acquire petroleum oil hydrocarbons. Usually some natural gas is produced along with the oil. A well that is designed to produce mainly or only gas may be termed a gas well.-History:The earliest...
in history at a vertical depth of 35050 ft (10,683 m) and measured depth of 35055 ft (10,685 m) in the Tiber Oil Field at Keathley Canyon
Keathley Canyon
Keathley Canyon is an undersea canyon in the in the United States Exclusive Economic Zone in the Gulf of Mexico.The Canyon is rich in oil fields. The major oilfields at the Keathley Canyon are Tiber, Kaskida, Lucius, and Buckskin. Many oil companies, including Chevron Corporation, BP, Anadarko...
block 102, approximately 250 miles (402.3 km) southeast of Houston, in 4132 feet (1,259.4 m) of water. On 20 April 2010, while drilling at the Macondo Prospect
Macondo Prospect
The Macondo Prospect is an oil and gas prospect in the United States Exclusive Economic Zone of the Gulf of Mexico, off the coast of Louisiana...
, an explosion on the rig
Deepwater Horizon explosion
The Deepwater Horizon drilling rig explosion refers to the April 20, 2010 explosion and subsequent fire on the Deepwater Horizon semi-submersible Mobile Offshore Drilling Unit , which was owned and operated by Transocean and drilling for BP in the Macondo Prospect oil field about southeast of the...
caused by a blowout
Blowout (well drilling)
A blowout is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed....
killed 11 crewmen and ignited a fireball
Fireball
A fireball is a somewhat spherical mass of fire, such that is caused by an explosion or a firestorm.It may also refer to:- Science and technology :* Ryan FR Fireball, an American aircraft* Fireball , a sailing boat...
visible from 35 miles (56.3 km) away. The resulting fire could not be extinguished and, on 22 April 2010, Deepwater Horizon sank, leaving the well gushing at the seabed
Seabed
The seabed is the bottom of the ocean.- Ocean structure :Most of the oceans have a common structure, created by common physical phenomena, mainly from tectonic movement, and sediment from various sources...
and causing the largest offshore oil spill
Oil spill
An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially marine areas, due to human activity, and is a form of pollution. The term is mostly used to describe marine oil spills, where oil is released into the ocean or coastal waters...
in U.S. history.
Design
Deepwater Horizon was a fifth-generation, RBS-8D design (i.e. model type), deepwater, dynamically positionedDynamic positioning
Dynamic positioning is a computer controlled system to automatically maintain a vessel's position and heading by using its own propellers and thrusters...
, column-stabilized, semi-submersible mobile offshore drilling unit
Offshore drilling
Offshore drilling refers to a mechanical process where a wellbore is drilled through the seabed. It is typically carried out in order to explore for and subsequently produce hydrocarbons which lie in rock formations beneath the seabed...
, designed to drill subsea
Subsea
Subsea is a general term frequently used to refer to equipment, technology, and methods employed in marine biology, undersea geology, offshore oil and gas developments, underwater mining, and offshore wind power industries.- Oil and gas :...
wells for oil exploration and production using an 18.75 in (476.3 mm), blowout preventer
Blowout preventer
A blowout preventer is a large, specialized valve used to seal, control and monitor oil and gas wells. Blowout preventers were developed to cope with extreme erratic pressures and uncontrolled flow emanating from a well reservoir during drilling. Kicks can lead to a potentially catastrophic...
, and a 21 in (533.4 mm) outside diameter marine riser.
Deepwater Horizon was the second semi-submersible rig constructed of a class of two, although Deepwater Nautilus
Deepwater Nautilus
Deepwater Nautilus is an ultra-deepwater, semi-submersible offshore drilling rig. Built in 2000 in South Korea, she is owned by Transocean, registered in Panama, and leased to Royal Dutch Shell for drilling operations in the Gulf of Mexico until December 2011.-Description:Deepwater Nautilus is a...
, its predecessor, is not dynamically positioned. The rig was 396 by and capable of operating in waters up to 8000 feet (2,438.4 m) deep, to a maximum drill depth of 30000 ft (9,144 m), and in 2010 was one of approximately 200 deepwater offshore rigs capable of drilling in waters more than 5000 ft (1,524 m). Its American Bureau of Shipping
American Bureau of Shipping
The American Bureau of Shipping is a classification society, with a mission to promote the security of life, property and the natural environment, primarily through the development and verification of standards for the design, construction and operational maintenance of marine-related facilities...
(ABS) class notations were "A1, Column Stabilized Drilling Unit, AMS, ACCU, DPS-3".
In 2002, the rig was upgraded with "e-drill," a drill monitoring system whereby technical personnel based in Houston, Texas, received real-time
Real-time computing
In computer science, real-time computing , or reactive computing, is the study of hardware and software systems that are subject to a "real-time constraint"— e.g. operational deadlines from event to system response. Real-time programs must guarantee response within strict time constraints...
drilling data from the rig and transmitted maintenance and troubleshooting information.
Advanced systems played a key role in the rig's operation, from pressure and drill monitoring technology, to automated shutoff systems and modelling systems for cementing. The OptiCem cement modelling system, used by Halliburton in April 2010 for BP's Gulf of Mexico drill, played a crucial part in cement slurry mix and support decisions. These decisions have become a focus for investigations into the explosion on the rig that month.
Construction and ownership
Deepwater Horizon was built for R&B Falcon (which later became part of TransoceanTransocean
Transocean Ltd. is one of the world's largest offshore drilling contractors. The company rents floating mobile drill rigs, along with the equipment and personnel for operations, to oil and gas companies at an average daily rate of US$282,700...
) by Hyundai Heavy Industries
Hyundai Heavy Industries
Hyundai Heavy Industries Co., Ltd. is the world's largest shipbuilding company, headquartered in Ulsan, South Korea. The company is a subsidiary of Hyundai Heavy Industries Group...
in Ulsan
Ulsan
Ulsan , officially the Ulsan Metropolitan City, is South Korea's seventh largest metropolis with a population of over 1.1 million. It is located in the south-east of the country, neighboring Busan to the south and facing Gyeongju to the north and the Sea of Japan to the east.Ulsan is the...
, South Korea. Construction started in December 1998, the keel
Keel
In boats and ships, keel can refer to either of two parts: a structural element, or a hydrodynamic element. These parts overlap. As the laying down of the keel is the initial step in construction of a ship, in British and American shipbuilding traditions the construction is dated from this event...
was laid on 21 March 2000, and the rig was delivered on 23 February 2001, after the acquisition of R&B Falcon by Transocean.
Transocean, through its Steinhausen, Switzerland
Steinhausen, Switzerland
Steinhausen is a city in the canton of Zug in Switzerland.-Geography:Steinhausen has an area, , of . Of this area, 50.5% is used for agricultural purposes, while 15.1% is forested...
subsidiary Triton Asset Leasing GmbH, operated the rig under the Marshalese
Marshall Islands
The Republic of the Marshall Islands , , is a Micronesian nation of atolls and islands in the middle of the Pacific Ocean, just west of the International Date Line and just north of the Equator. As of July 2011 the population was 67,182...
flag of convenience
Flag of convenience
The term flag of convenience describes the business practice of registering a merchant ship in a sovereign state different from that of the ship's owners, and flying that state's civil ensign on the ship. Ships are registered under flags of convenience to reduce operating costs or avoid the...
. The rig was leased to BP on a 3 year contract for deployment in the Gulf of Mexico
Gulf of Mexico
The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...
following construction, the lease being renewed in 2004 for a year, 2005 for 5 years, and 2009 for a further 3 years covering 2010 - 2013. The latter contract was worth $544 million, or $496,800 per day for 3 years, for the "bare rig", with crew, gear and support vessels estimated to cost the same per day again.
According to R&B Falcon's SEC filings for 2001, the transfer document between R&B Falcon and Transocean was dated 17 August 2001, and the rig was specified as "official registration number of 29273-PEXT-1, IMO No. 8764597, with Gross Tonnage of 32,588 and with Net Tonnage of 9,778" and the transfer value as . As at 2010, the rig was insured for , the sum covering its replacement cost and wreckage removal.
Drilling operations
Deepwater Horizon worked on wells in the AtlantisAtlantis Oil Field
The Atlantis oil field is the third largest oil field in the Gulf of Mexico. The field was discovered in 1998 and is located at the Green Canyon blocks 699, 700, 742, 743, and 744 in United States federal waters in the Gulf of Mexico about from the coast of Louisiana...
(BP 56%, BHP Billiton
BHP Billiton
BHP Billiton is a global mining, oil and gas company headquartered in Melbourne, Australia and with a major management office in London, United Kingdom...
44%) and Thunder Horse (BP 75%, ExxonMobil
ExxonMobil
Exxon Mobil Corporation or ExxonMobil, is an American multinational oil and gas corporation. It is a direct descendant of John D. Rockefeller's Standard Oil company, and was formed on November 30, 1999, by the merger of Exxon and Mobil. Its headquarters are in Irving, Texas...
25%) oil field
Oil field
An oil field is a region with an abundance of oil wells extracting petroleum from below ground. Because the oil reservoirs typically extend over a large area, possibly several hundred kilometres across, full exploitation entails multiple wells scattered across the area...
s. It was described at times as a "lucky" and "celebrated" rig, and in 2007 was still described as "one of the most powerful rigs in the world". In 2006 it discovered oil in the Kaskida oil field
Kaskida Oil Field
The Kaskida Oil Field is an offshore oil field located in the Keathley Canyon block 292 of the United States sector of the Gulf of Mexico, south-west of New Orleans, Louisiana...
, and in 2009 the "giant" Tiber field. The well in the Tiber field has a vertical depth of 35050 ft (10,683 m) and a measured depth of 35055 ft (10,685 m), below 4132 ft (1,259.4 m) of water. The well was the deepest oil well in the world, and more than 5000 feet (1,524 m) further below the seabed than the rig's official drilling specification stated on the company's fleet list.
In February 2010, Deepwater Horizon commenced drilling an exploratory well at the Macondo Prospect (Mississippi Canyon
Mississippi Canyon
The Mississippi Canyon is an undersea canyon in the Central Gulf of Mexico, south of Louisiana. According to the U.S. Geological Survey GLORIA Mapping Program, it is the dominant feature of the north-central Gulf of Mexico. According to GCAGS Transactions, it has an average width of , and a length...
Block 252), about 41 miles (66 km) off the southeast coast of Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, at a water depth of approximately 5000 feet (1,524 m). The Macondo prospect exploration rights were acquired by BP in 2009, with the prospect jointly owned by BP (65%), Anadarko
Anadarko Petroleum Corporation
Anadarko Petroleum Corporation is one of the world’s largest independent oil and gas exploration and production companies, with approximately 2.3 billion barrels of oil equivalent of proved reserves and production of 206 million BOE as of December 31, 2008. Anadarko employs a worldwide...
(25%) and MOEX Offshore 2007
Mitsui
is one of the largest corporate conglomerates in Japan and one of the largest publicly traded companies in the world.-History:Founded by Mitsui Takatoshi , who was the fourth son of a shopkeeper in Matsusaka, in what is now today's Mie prefecture...
(10%). Deepwater Horizon was still working on the Macondo site on 20 April 2010, when a violent explosion occurred leading to destruction of the rig and resulting oil spill. The well was in the final stages of completion at the time; its cement casing was injected and hardening, and the rig was due to move shortly to its next role as a semi-permanent production platform at the Nile site following by a return to the Kaskida field. The exploratory work was described as "concluded" and permission had already been requested from MMS to terminate operations at the Macondo site.
During its operational lifetime, the rig was actively in operation for 93% of its working life (2,896 of 3,131 days). The remainder partly relates to time spent between sites.
Regulation, safety, and inspection
The Minerals Management ServiceMinerals Management Service
The Bureau of Ocean Energy Management, Regulation and Enforcement , formerly known as the Minerals Management Service , was an agency of the United States Department of the Interior that managed the nation's natural gas, oil and other mineral resources on the outer continental shelf...
(renamed on 18 June 2010 to the Bureau of Ocean Energy Management, Regulation and Enforcement, or Bureau of Ocean Energy (BOE)) is the regulatory and inspecting body for offshore oil drilling and rigs in the United States of America. According to an Associated Press
Associated Press
The Associated Press is an American news agency. The AP is a cooperative owned by its contributing newspapers, radio and television stations in the United States, which both contribute stories to the AP and use material written by its staff journalists...
investigation, certain safety documentation and emergency procedure information, including documentation for the exact incident that later occurred, was absent. The exact number of required monthly inspections varied over time, with the required monthly inspection for the first 40 months but after that around 25% of inspections were omitted, although the investigation notes this is partly expected, since there are circumstances such as weather and movement which preclude an inspection. Reports of the last three inspection for 2010 were provided under Freedom of Information
Freedom of information
Freedom of information refers to the protection of the right to freedom of expression with regards to the Internet and information technology . Freedom of information may also concern censorship in an information technology context, i.e...
laws. Each of these inspections had taken two hours or less.
During its lifetime the rig received 5 citations for non-compliance, 4 of which were in 2002 (safety, including the blowout preventer) and the other in 2003 (pollution). A sixth citation in 2007 related to non-grounded
Ground (electricity)
In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....
electrical equipment was later withdrawn when the equipment was determined to be compliant with regulations. Overall the Deepwater Horizons safety record was "strong" according to a drilling consultant reviewing the information. In 2009 the Minerals Management Service "herald[ed] the Deepwater Horizon as an industry model for safety". According to AP's investigation "its record was so exemplary, according to MMS officials, that the rig was never on inspectors' informal 'watch list' for problem rigs".
Explosion and oil spill
At CDT on 20 April 2010, during the final phases of drilling the exploratory well at Macondo, a geyser of seawater erupted from the marine riser onto the rig, shooting 240 ft (73.2 m) into the air. This was soon followed by the eruption of a slushy combination of mud, methaneMethane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
gas, and water. The gas component of the slushy material quickly transitioned into a fully gaseous state and then ignited into a series of explosions and then a firestorm. An attempt was made to activate the blowout preventer
Blowout preventer
A blowout preventer is a large, specialized valve used to seal, control and monitor oil and gas wells. Blowout preventers were developed to cope with extreme erratic pressures and uncontrolled flow emanating from a well reservoir during drilling. Kicks can lead to a potentially catastrophic...
, but it failed.
At the time of the explosion, there were 126 crew on board; seven were employees of BP, 79 of Transocean, there were also employees of various other companies involved in the operation of the rig, including Anadarko
Anadarko Petroleum Corporation
Anadarko Petroleum Corporation is one of the world’s largest independent oil and gas exploration and production companies, with approximately 2.3 billion barrels of oil equivalent of proved reserves and production of 206 million BOE as of December 31, 2008. Anadarko employs a worldwide...
, Halliburton
Halliburton
Halliburton is the world's second largest oilfield services corporation with operations in more than 70 countries. It has hundreds of subsidiaries, affiliates, branches, brands and divisions worldwide and employs over 50,000 people....
and M-I SWACO. Eleven workers were presumed killed in the initial explosion. The rig was evacuated, with numerous injured workers airlifted to medical facilities. After burning for approximately 36 hours, Deepwater Horizon sank on 22 April 2010. The remains of the rig were located resting on the seafloor
Seabed
The seabed is the bottom of the ocean.- Ocean structure :Most of the oceans have a common structure, created by common physical phenomena, mainly from tectonic movement, and sediment from various sources...
approximately 5000 ft (1,524 m) deep at that location, and about 1300 ft (396.2 m) (quarter of a mile) northwest of the well.
The resultant oil spill
Deepwater Horizon oil spill
The Deepwater Horizon oil spill is an oil spill in the Gulf of Mexico which flowed unabated for three months in 2010, and continues to leak fresh oil. It is the largest accidental marine oil spill in the history of the petroleum industry...
continued until July 15 when it was temporarily closed by a cap. Relief well
Relief well
A relief well is a well drilled to intersect an oil or gas well that has experienced a blowout. Specialized liquid, such as heavy drilling mud followed by cement, can then be pumped down the relief well in order to stop the flow from the reservoir in the damaged well.The first use of a relief well...
s were used to permanently seal the well, which was declared "effectively dead" on September 19, 2010.
Aftermath
Transocean received an early partial settlement for total loss of the Deepwater Horizon of around 5 May 2010. Financial analystFinancial analyst
A financial analyst, securities analyst, research analyst, equity analyst, or investment analyst is a person who performs financial analysis for external or internal clients as a core part of the job.-Job:...
s note that the insurance recovery is likely to outweigh the value of the rig (although not necessarily its replacement value) and any liabilities - the latter estimated at up to .
Litigation, ultimate roll call of damage, and the scope of final insurance recovery are all unknown , with analysts reporting that the aftermath is of unprecedented scale and complexity compared to previous disasters which themselves took many years to unfold and resolve. A July 2010 analysis by the Financial Times
Financial Times
The Financial Times is an international business newspaper. It is a morning daily newspaper published in London and printed in 24 cities around the world. Its primary rival is the Wall Street Journal, published in New York City....
on the aftermath cites legal sources as saying that "at some point the scale of the litigation
Deepwater Horizon litigation
Litigation due to the loss of the Deepwater Horizon and resulting oil spill commenced shortly after the initial loss of the rig in April 2010.A large number of claims and class actions have already been filed, although many claims are expected to be met administratively from the fund set up for...
becomes so large that it really is novel", that "the situation is likely be complicated further because the variety of probable cases means it will be hard to aggregate them into so-called class action
Class action
In law, a class action, a class suit, or a representative action is a form of lawsuit in which a large group of people collectively bring a claim to court and/or in which a class of defendants is being sued...
s" and that there is "no way to put this in historical context because we have never faced anything like this before". As with the Exxon Valdez disaster, litigation is being discussed in terms of a 20 year timescale.
See also
- Deepwater Horizon litigationDeepwater Horizon litigationLitigation due to the loss of the Deepwater Horizon and resulting oil spill commenced shortly after the initial loss of the rig in April 2010.A large number of claims and class actions have already been filed, although many claims are expected to be met administratively from the fund set up for...
- Notable offshore well blowouts
- Ixtoc I oil spill
- Kola Superdeep BoreholeKola Superdeep BoreholeThe Kola Superdeep Borehole is the result of a scientific drilling project of the Soviet Union in Kola Peninsula. The project attempted to drill as deep as possible into the Earth's crust. Drilling began on 24 May 1970 using the Uralmash-4E, and later the Uralmash-15000 series drilling rig. A...
- Atlantis PQAtlantis PQAtlantis PQ is a BP plc and BHP Billiton joint venture semi-submersible oil platform on permanent location over the Green Canyon Atlantis Oil Field in deepwater Gulf of Mexico, south of New Orleans. The "PQ" identifies the platform as being a production facility with crew quarters.The vessel's...
- Ocean RangerOcean RangerOcean Ranger was a semi-submersible mobile offshore drilling unit that sank in Canadian waters on 15 February 1982. It was drilling an exploration well in the Grand Banks area, east of St. John's, Newfoundland, for Mobil Oil of Canada, Ltd. with 84 crew members on board when it sank...
- Piper AlphaPiper AlphaPiper Alpha was a North Sea oil production platform operated by Occidental Petroleum Ltd. The platform began production in 1976, first as an oil platform and then later converted to gas production. An explosion and resulting fire destroyed it on 6 July 1988, killing 167 men, with only 61...
- Thunder Horse PDQThunder Horse PDQThunder Horse PDQ is a BP plc and ExxonMobil joint venture semi-submersible oil platform on location over the Mississippi Canyon Thunder Horse oil field , in deepwater Gulf of Mexico, southeast of New Orleans, moored in waters of...
- Transocean John ShawTransocean John ShawTransocean John Shaw is a semi-submersible drilling rig designed by Friede & Goldman as a self-propelled modified & enhanced pacesetter, built and delivered in 1982 by Mitsui Engineering & Shipbuilding Ltd. in Japan....
External links
- Transocean official website
- Deepwater Horizon detail at Transocean's website and at RigZone.com
- Photograph of Deepwater Horizon in 2004 at Geographic.org - detailed media description of the events of the day of the Deepwater Horizon explosion (yahoo news mirror)
- Photo history of the fire and loss
- MMS reading room on Deepwater Horizon, including Freedom of Information publications