Offshore oil and gas in California

In 1792, when the English explorer James Cook anchored his ship in the Santa Barbara Channel, his navigator George Vancouver wrote that the sea was “... covered with a thick, slimy substance,” and added “... the sea had the appearance of dissolved tar floating on its surface, which covered the ocean in all directions within the limits of our view.”[2] In 1865, oil geologist Charles Jackson wrote: A description of the oil and gas seeps offshore southern California can be found in a report on the California Division of Oil and Gas's website.

[4] The report is accompanied by a map, showing the locations of offshore petroleum seeps from Point Arguello (north of Santa Barbara) to Mexico.

[6] A number of other coastal fields were extended offshore in Santa Barbara, Ventura, Los Angeles, and Orange counties, usually by directional drilling.

However, the US Congress passed the Outer Continental Shelf Act in 1953, which recognized state ownership of the seabed within 3 nautical miles (6 km) of the shore.

[10] The resulting oil slick came ashore along 35 miles (56 km) of coastline in Santa Barbara County, and turned public opinion against offshore drilling in California.

[14] In 1990, President George H. W. Bush issued an executive moratorium banning new federal leasing through the year 2000 in many offshore areas, including California.

In 2008 both Plains Exploration & Production (PXP) and ExxonMobil offered competing proposals to the state to drill wells into Tranquillon Ridge field, offshore Santa Barbara County.

Nine active offshore drilling and production locations remain in state and municipal waters: one platform and one artificial island in the Santa Barbara Channel, and four artificial islands and three platforms from the offshore portion of the Wilmington Oil Field in San Pedro Bay/Long Beach Harbor.

[25] Twenty seven platforms lie along the Southern California coast from Huntington Beach to Point Conception in Santa Barbara County.

[27] Of the 23 oil platforms surrounding the coast of California, eight are no longer in usage or, due to terminated leases, are not allowed to resume production.

[29] As of 2021, the Biden Administration announced that an environmental analysis would be conducted to establish the effects of complete or partial decommissioning of oil and gas platforms.

This includes the Rigs-to Reefs program that proposes to only partially remove parts of the oil platform, keeping a majority of the habitat intact for the wildlife.

The total potential petroleum resource in offshore central California may be 4 to 6 billion bbls oil and 5 to 7 trillion cubic feet of gas, per 1996 estimates by USGS and MMS.

[33] In 2020, the Trump administration had a proposal under development to outline potential sales near Southern California and other coastal areas of the United States.