Flash player not installed.

Our Businesses
Oil and Gas
United States
Elk Hills
Long Beach
Midcontinent and Other
Middle East Region
Latin America
Doing Business with Us
Midstream and Marketing
Long Beach 

Occidental has oil and gas operations in Long Beach, California, where it has interests in the Wilmington Field, one of the 10 largest oilfields in the United States. Oxy has a stake in over 80 percent of the properties that overlie the Wilmington Field, where we operate on behalf of the state of California and the city of Long Beach. Oxy Long Beach, Inc., includes THUMS Long Beach Company, which operates the offshore portion of the Wilmington Field; Tidelands Oil Production Company, which operates the onshore portion of the Wilmington Field; and two additional smaller leases.

THUMS Long Beach Company

THUMS comprises four man-made islands in Long Beach Harbor, as well as onshore facilities. When Oxy acquired THUMS in 2000, it retained the name derived from the original consortium of operators: Texaco, Humble, Unocal, Mobil and Shell.

Under the terms of an agreement between THUMS, the city of Long Beach and the state of California, the THUMS islands were designed to blend in with the surrounding coastal environment. Drilling rigs and other above-ground equipment are camouflaged and sound-proofed, and wellheads and pipelines are located below the islands’ surface to enhance the appearance of the harbor and skyline.

The THUMS islands were named after four astronauts who died in the line of duty in the early years of the U.S. space program. Island Freeman encompasses about 12 acres, while islands Grissom, White and Chaffee cover approximately 10 acres each.

THUMS’ unique combination of production functionality, visual appeal and environmental and safety features has garnered the facility dozens of awards and recognition from local, state and national organizations. The Wildlife Habitat Council (WHC), a nonprofit organization that helps landowners enhance wildlife habitat, has certified all four THUMS’ islands for commendable wildlife habitat management and environmental education programs. Since 2004, the wildlife team at THUMS has worked with WHC to establish California plant habitats on the islands.


Oxy acquired Tidelands Oil Production Company in 2006. Tidelands is the contractor that operates the West Wilmington Field for the city of Long Beach and the state of California. Tidelands’ onshore production facilities and drilling operations are located in and around the port of Long Beach, near the THUMS operation. Advanced exploration technologies such as reservoir characterization and 3-D visualization, have been employed in the field.