Federal and state authorities are investigating the cause of the deadly explosion and fire at a natural gas drilling rig in southeastern Oklahoma on Monday. Five workers died in what appears to be one of the country’s deadliest onshore drilling accidents.
[pdf] The bodies of five workers, including one Texan, were recovered Tuesday after an explosion ripped through a drilling rig in Oklahoma, triggering what appears to be the nation's deadliest oil and gas accident since the 2010 Deepwater Horizon disaster in the Gulf of Mexico.
[pdf] 
As of June 2010, there were over 620 mobile offshore drilling rigs (jackups, semisubs, drillships, barges, etc.) available for service in the worldwide offshore rig fleet. .
Offshore drilling is a mechanical process where a is drilled below the seabed. It is typically carried out in order to explore for and subsequently extract that lies in rock formations beneath the. .
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. .
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 .
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) .
• • • • • •
[pdf]