Kulluk was an ice-strengthened that was used for oil exploration in the Arctic waters. She was constructed by in in 1983 and operated in the Canadian Arctic until 1993 when she was mothballed for over a decade. In 2005, she was purchased and extensively refurbished by Shell PLC for drilling off the .
[pdf] The and the topsides of the Perdido were constructed separately and then assembled in its final position in the Gulf of Mexico. The Perdido's hull or spar was constructed by in . A barge shipped the 22,000 tonne spar 13,200 kilometres (8,200 miles) from the to the Gulf of Mexico. After floating the spar, it was towed to its final home above the Alaminos canyon 320 kilometres (120 miles) fr.
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Offshore drilling is a mechanical process where a wellbore is drilled below the seabed. It is typically carried out in order to explore for and subsequently extract petroleum that lies in rock formations beneath the seabed. Most commonly, the term is used to describe drilling activities on the continental shelf,. .
Around 1891, the first submerged oil wells were drilled from platforms built on piles in the fresh waters of the in . The wells were developed by small local. .
Notable offshore fields include:• the • the (offshore , , , and )• (in the and , part of the Ventura Basin) .
Offshore oil production involves environmental risks, most notably from oil tankers or pipelines transporting oil from the platform to onshore facilities, and from leaks and accidents on the platform (e.g. and .
• 17Apr2009 DC Appellate Decision stopping offshore Alaska Oil Leases.• .
Offshore drilling is usually done from platforms generically known as mobile offshore drilling units (MODU), which can be of one of several. .
Offshore oil and gas production is more challenging than land-based installations due to the remote and harsher environment. Much of the innovation in the offshore petroleum. .
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