text: One of the world's deepest hubs is currently the Perdido in the Gulf of Mexico, floating in  of water. It is operated by Royal Dutch Shell and was built at a cost of $3 billion. The deepest operational platform is the Petrobras America Cascade FPSO in the Walker Ridge 249 field in  of water.
  Drilling platforms
  Offshore drilling is usually done from platforms generically known as mobile offshore drilling units (MODU), which can be of one of several formats, depending on the water depth:
  Jackup rig
  Submersible drilling rig
  Semi-submersible platform
  Drillship
  Main offshore fields
  Notable offshore fields include:
  the North Sea
  the Gulf of Mexico (offshore Texas, Louisiana, Mississippi, and Alabama)
  California (in the Los Angeles Basin and Santa Barbara Channel, part of the Ventura Basin)
  the Caspian Sea (notably some major fields offshore Azerbaijan)
  the Campos and Santos Basins off the coasts of Brazil
  Newfoundland and Nova Scotia (Atlantic Canada)
  several fields off West Africa most notably west of Nigeria and Angola
  offshore fields in South East Asia and Sakhalin, Russia
  major offshore oil fields are located in the Persian Gulf such as Safaniya, Manifa and Marjan which belong to Saudi Arabia and are developed by Saudi Aramco.
  fields in India (Mumbai High, K G Basin-East Coast Of India, Tapti Field, Gujarat, India)
  the Taranaki Basin in New Zealand
  the Kara Sea north of Siberia
  the Arctic Ocean off the coasts of Alaska and Canada's Northwest Territories