Offshore platforms are huge structures equipped with resources to drill wells and extract oil and gas deep inside the ocean. They boast storage facilities for crude and gas till they are transported to refineries, and sometimes may also have facilities to provide accommodation to the workforce. Depending on the requirements, an oil platform may be floating or fixed to the ocean floor.
The first offshore platform are drilled on a lake in 1890s, the first platform built on piles in the fresh waters of the Grand Lake St. marys in Ohio.
On Grand Lake St. Marys, oilmen built derricks atop such cribs. Pipelines carried the oil from producing these ohio offshore wells to storage tanks hastily constructed on shore.
The first submerged oil wells in salt water were drilled in 1896, the portion of the Summerland field extending under the Santa Barbara Channel in California. The wells were drilled from piers extending from land out into the channel.
The wells were developed by small local companies such as Bryson, Riley Oil, German-American and Banker's Oil.
Riley Oil Company drilled more than 100 oil wells in the reservoir, including the Riley-Mosher well, which began producing in 1886 and still produced 35 barrels a day as late as 1910. By then, however, the Ohio offshore oil boom was over.
In 1913 the New York Times reported the reservoir “contains more than 100 oil wells,” but oil men had moved on. Production on the waters of Grand Lake St. Marys lost its economic incentive when Spindletop’s astounding yield drove the price of Ohio crude below 15 cents a barrel.
Other notable early submerged drilling activities occurred on the Canadian side of Lake Erie in the 1900s and Caddo Lake in Louisiana in the 1910s. Shortly thereafter wells were drilled in tidal zones along the Texas and Louisiana gulf coast. The Goose Creek Oil Field near Baytown, Texas is one such example. In the 1920s drilling activities occurred from concrete platforms in Venezuela's Lake Maracaibo.
One of the oldest subsea wells is the Bibi Eibat well, which came on stream in 1923 in Azerbaijan.The well was located on an artificial island in a shallow portion of the Caspian Sea. In the early 1930s, the 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 field 1 mile (1.6 km) offshore of Calcasieu Parish, Louisiana in 14 feet (4.3 m) of water.
In 1945, concern for American control of its offshore oil reserves caused President Harry Truman to issue an Executive Order unilaterally extending American territory to the edge of its continental shelf, an act that effectively ended the 3-mile limit "freedom of the seas" regime.
In 1946, Magnolia Petroleum (now ExxonMobil) drilled at a site 18 miles (29 km) off the coast, erecting a platform in 18 feet (5.5 m) of water off St. Mary Parish, Louisiana.
In early 1947, Superior Oil erected a drilling and production platform in 20 feet (6.1 m) of water some 18 miles (29 km) off Vermilion Parish, La. But it was Kerr-McGee Oil Industries (now Anadarko 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 actually drilled a discovery from their Vermilion platform farther offshore. In any case, that made Kerr-McGee's well the first oil discovery drilled out of sight of land.
When offshore drilling moved into deeper waters of up to 30 metres (98 ft), fixed platform rigs were built, until demands for drilling equipment was needed in the 100 feet (30 m) to 120 metres (390 ft) depth of the Gulf of Mexico, the first jack-up rigs began appearing from specialized offshore drilling contractors such as forerunners of ENSCO International.
The first semi-submersible resulted from an unexpected observation in 1961. Blue Water Drilling Company owned and operated the four-column submersible Blue Water Rig No.1 in the Gulf of Mexico for Shell Oil Company. As the pontoons were not sufficiently buoyant to support the weight of the rig and its consumables, it was towed between locations at a draught mid-way between the top of the pontoons and the underside of the deck. It was noticed that the motions at this draught were very small, and Blue Water Drilling and Shell jointly decided to try operating the rig in the floating mode. The concept of an anchored, stable floating deep-sea platform had been designed and tested back in the 1920s by Edward Robert Armstrong for the purpose of operating aircraft with an invention known as the 'seadrome'. The first purpose-built drilling semi-submersible Ocean Driller was launched in 1963. Since then, many semi-submersibles have been purpose-designed for the drilling industry mobile offshore fleet.
The first offshore drillship was the CUSS 1 developed for the Mohole project to drill into the Earth's crust.
Offshore drilling often receives a bad reputation for causing environment problems, however there are benefits to offshore drilling. Offshore rigs help the local economy, create jobs, reduce dependency on foreign fuels and surprisingly also create homes for marine life.
Surprisingly the environment can benefit from offshore drilling, if there are no accidents. Offshore rigs are massive structures in the ocean that attract a wide variety of marine life. Fish, birds and other sea creatures come to the rig and make it their home. The rig acts as an artificial reef that helps life flourish as many animals use it for breeding.
Photo courtesy of American Oil and Gas History (AOGH)
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