Deepwater drilling

Drilling in deep waters can be performed by two main types of mobile deepwater drilling rigs: semi-submersible drilling rigs and drillships. Drilling can also be performed from a fixed-position installation such as a fixed platform, or a floating platform, such as a spar platform, a tension-leg platform, or a semi-submersible production platform. • Fixed Platform (FP) – A Fixed Platform consists of a tall, (usually) steel structure that supports a deck. Because the Fixed Platform is anchored to the sea floor, it is very costly to build. This type of platform can be installed in water depth up to . • Jack-Up Rig – Jack-up rigs are mobile units with a floating hull that can be moved around; once they arrived at the desired location, the legs are lowered to the seafloor and locked into place. Then the platform is raised up out of the water. That makes this type of rig safer to work on because weather and waves are not an issue. • Compliant Tower (CT) Platform – A compliant tower is a particular type of fixed platform. Both are anchored to the seafloor, and both workplaces are above the water surface. However, the compliant tower is taller and narrower and can operate up to 1 kilometer (3,000 feet) water depth. ==2010 Deepwater Horizon oil spill==

On 20 April 2010, a BP deepwater oil rig (Deepwater Horizon) exploded, killing 11 and releasing 750,000 cubic meters (200 million gallons) of oil into the Gulf of Mexico. With those numbers, many scientists consider this disaster to be one of the worst environmental disasters in the history of the US. A large number of animal deaths have resulted from the release of the oil. A Center study estimates that over 82,000 birds, about 6,000 sea turtles, and nearly 26,000 marine mammals were killed from either the initial explosion or the oil spill. Deepwater wellbore integrity has become an increasingly important point in the field of petroleum engineering. ==See also==

• Deepwater Drilling: How It Works | Chevron | Video. chevron.com. • HowStuffWorks "Ultra Deep Water Oil Drilling". science.howstuffworks.com. • Rigzone – Deepwater Gulf of Mexico Drilling Activity to Keep Rising. rigzone.com. April 24, 2013.