Stop #6: Wilmington Oil Field Palos Verdes Geology Field Trip << | Home | >>

The Wilmington Oil Field extends from the Wilmington District of Los Angeles, across Terminal Island, through Long Beach Harbor and offshore from the City of Long Beach. From its discovery in 1932 to 1973 it produced more than 1.617 bi1ion barrels of oil and 996 billion cubic feet of natural gas, and it continues to be of great economic significance to the State of California. Since the early 1940's subsidence of the ground surface has been a major problem in the area. The maximum subsidence, about 10 meters, occurred in the northeast portion of Terminal Island. Because of the low elevation of the harbor area, it was necessary to build dikes to protect facilities from the ocean.

The subsidence caused severe problems in this heavily industrialized district. Bridges were jacked up and straightened; high dikes were built to protect a large power plant from encroachment by the ocean; and numerous buildings were damaged or had to be raised. About the only advantage was the deepening of ship channels without dredging. Since 1958, the rate of subsidence has been greatly reduced by pumping salt water into the reservoirs to replace the oil and gas withdrawn. This nearly stabilizes the fluid pressure in the system, helps flush out more oil and gas, and reduces subsidence.

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Stop #6: Wilmington Oil Field   << | Home | >>