Ventura Oil Field

The Ventura Oil Field is a large and currently productive oil field in the hills immediately north of the city of Ventura in southern California in the United States. It is bisected by California State Route 33, the freeway connecting Ventura to Ojai, and is about eight miles (13 km) long by two across, with the long axis aligned east to west. Discovered in 1919, and with a cumulative production of just under a billion barrels of oil as of 2008, it is the tenth-largest producing oil field in California, retaining approximately 50 million barrels in reserve, and had 423 wells still producing. As of 2009^[update] it was entirely operated by Aera Energy LLC.

The oil field is on and beneath the ranges of hills northwest, north and northeast of the city of Ventura. The Ventura River, flowing down from Ojai, cuts through the field, and empties into the Pacific Ocean at Ventura. Native vegetation in the hills is predominantly chaparral and coastal sage scrub, and riparian woodland is found along the course of the Ventura River. Terrain on the hills is steep, and the roads to well pads, tanks, and other infrastructure make numerous switchbacks. Most of the field is hidden from view from the city because of the first steep range of hills. The oil field is one of several following the east-west trend of the Transverse Ranges at this point: to the west are the San Miguelito Oil Field and the Rincon Oil Field, and to the east, across the Santa Clara River valley, the large South Mountain Oil Field adjacent to Santa Paula and the smaller Saticoy Oil Field along the Santa Clara River east of Saticoy. To the north are the smaller Ojai and Santa Paula fields. Total productive area of the field, projected to the surface, encompasses 3,410 acres (13.8 km²).

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