These platforms can take the form of either floating semisubmersible platforms or drill ships. The basic idea behind their design is that, once the well has been drilled, much of the production equipment can be mounted on the seafloor and the petroleum pumped to the surface facilities through flexible risers.. .
This platform is essentially a king-sized version of the Sea Star platform, except the tension legs extend from the ocean floor to the platform itself. It experiences more horizontal motion and a certain degree of vertical motion, but it allows oil companies to drill at. .
Finally, if you absolutely need to drill a hole at a depth of 10,000 feet (3,048 meters), then the spar platform is the oil rig for you. With this design, the drilling platform sits atop a giant, hollow cylindrical hull. The other end of the cylinder descends around. .
This approach takes the idea of mounting the wellhead on the seafloor and applies it to even greater depths — 7,000 feet (2,134 meters) or more. Once the well has been drilled by a. .
Deep-sea waters reach nearly freezing temperatures, contain pressures great enough to crack iron casings and are subject to rough, deep-sea currents. Engineers have to design equipment that can stand up to the pressure, while also preventing boiling oil.
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Mobile offshore Drilling Units (MODU) This type of rig is commonly used in connection with oil and/or natural gas drilling. There are more jackup rigs in the worldwide offshore rig fleet than other type of mobile offshore drilling rig. Other types of offshore rigs include semi-submersibles (which float on pontoon-like. .
A jackup rig or a self-elevating unit is a type of mobile platform that consists of a buoyant fitted with a number of movable legs, capable of raising its hull over the surface of the sea. The buoyant hull enables. .
Jackup rigs are so named because they are self-elevating with three, four, six and even eight movable legs that can be extended (“jacked”) above or below the hull. Jackups are. .
A jackup rig is a barge fitted with long support legs that can be raised or lowered. The jackup is maneuvered (self-propelled or by towing) into. .
An early design was the DeLong platform, designed by Leon B. DeLong. In 1949 he started his own company, DeLong Engineering & Construction Company. In 1950 he constructed.
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Development and production operations in the Arctic offshore as a result of exploration have been limited, with the exception of the Barents and Norwegian seas. In Alaska, exploration subsequent to the discovery of the Prudhoe Bay oilfield has focussed on the onshore and shallow coastal waters.SummaryExploration for petroleum in the Arctic is expensive and challenging both technically and logistically. In the. .
There are 19 geological making up the region. Some of these basins have experienced and , most notably the where oil was first produced in 1968 from .. .
Drilling in the peaked during the 1970s and 1980s, led by such companies as in the Sverdrup Basin of the Arctic Islands, and by and in the Beaufort S. .
In June 2007, a group of returned from a six-week voyage on a , the expedition called . They had travelled to the , an underwate. .
In the years post 2000, sedimentary basins offshore were believed by some geologists to have high potential for large oil discoveries. In a comprehensive study of the potential of Arctic basins published in 2008, the.
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