High Quality Content by WIKIPEDIA articles! The North Belridge Oil Field is a large oil field along California State Route 33 in the northwestern portion of Kern County, California, about 45 miles west of Bakersfield. It is contiguous with the larger South Belridge Oil Field to the southeast, in a region of highly productive and mature fields. Discovered in 1912, it has had a cumulative production of 136,553,000 barrels of oil, and retains 27,443,000 barrels in reserve, as of the end of 2006, making it the 40th largest oil field in the state.