Long Beach Oil Field

The Long Beach Oil Field is a large oil field underneath the cities of Long Beach and Signal Hill, California, in the United States. Discovered in 1921, the field was enormously productive in the 1920s, with hundreds of oil derricks covering Signal Hill and adjacent parts of Long Beach; largely due to the huge output of this field, the Los Angeles Basin produced one-fifth of the nation's oil supply during the early 1920s. In 1923 alone the field produced over 68 million barrels of oil, and in barrels produced by surface area, the field was the world's richest. The field is eighth-largest by cumulative production in California, and although now largely depleted, still officially retains around 5 million barrels of recoverable oil out of its original 950 million. 294 wells remained in operation as of the beginning of 2008, and in 2008 the field reported production of over 1.5 million barrels of oil. The field is currently run entirely by small independent oil companies, with the largest operator in 2009 being Signal Hill Petroleum, Inc.
The Long Beach field is one of many in the Los Angeles Basin now largely overbuilt with dense urban development. Even with the dramatic land use changes over the decades since its discovery, it remains moderately productive, with oil wells and oilfield infrastructure intermixed with commercial and residential development. The field underlies the northern portion of the city of Long Beach and most of the city of Signal Hill. In spite of its name, most of the productive area of the field underlies the small city of Signal Hill, which has a population of around 11,000. The main productive area of the field runs from northwest to southeast, about five miles long by one across, with the long axis following the Cherry Hill Fault Zone, which is part of the larger Newport–Inglewood Fault Zone, the most significant fault zone traversing the Los Angeles Basin. In the northwest, the oil field begins approximately near the junction of the San Diego Freeway and the 710 , and proceeds roughly paralleling the 405 freeway to near the intersection of Lakewood Boulevard and California State Route 1 at their traffic circle in Long Beach. A small portion of the field, no longer productive, is in the city of Lakewood, and another small isolated part of the field, the "Recreation Park Area", lies to the southeast of the main field. The total productive area of the entire field is 1,725 acres .

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