Oxnard Plain in the context of "Ventura County, California"

The Los Angeles Basin is a sedimentary basin located in Southern California, in a region known as the Peninsular Ranges. The basin is also connected to an anomalous group of east–west trending chains of mountains collectively known as the Transverse Ranges. The present basin is a coastal lowland area, whose floor is marked by elongate low ridges and groups of hills that is located on the edge of the Pacific plate. The Los Angeles Basin, along with the Santa Barbara Channel, the Ventura Basin, the San Fernando Valley, and the San Gabriel Basin, lies within the greater Southern California region. The majority of the jurisdictional land area of the city of Los Angeles physically lies within this basin.

On the north, northeast, and east, the lowland basin is bound by the Santa Monica Mountains and Puente, Elysian, and Repetto hills. To the southeast, the basin is bordered by the Santa Ana Mountains and the San Joaquin Hills. The western boundary of the basin is marked by the Continental Borderland and is part of the onshore portion. The California borderland is characterized by northwest trending offshore ridges and basins. The Los Angeles Basin is notable for its great structural relief and complexity in relation to its geologic youth and small size for its prolific oil production. Yerkes et al. identify five major stages of the basin's evolution, which began in the Upper Cretaceous and ended in the Pleistocene. This basin can be classified as an irregular pull-apart basin accompanied by rotational tectonics during the post-early Miocene.

Oxnard (/ˈɒksnɑːrd/ ) is a city in Ventura County in the U.S. state of California, United States. On California's Central Coast, it is the most populous city in Ventura County and the 22nd-most-populous city in California. Incorporated in 1903, Oxnard lies approximately 60 miles (97 km) northwest of downtown Los Angeles.

It is at the western edge of the fertile Oxnard Plain, adjacent to agricultural fields with strawberries, lima beans and other vegetable crops. Oxnard is also a major transportation hub in Southern California, with Amtrak, Union Pacific, Metrolink, Greyhound, and Intercalifornias stopping there. It also has a small regional airport, Oxnard Airport (OXR). The town also has significant connections to the nearby oil fields Oxnard Oil Field and the West Montalvo Oil Field. The high density of oil, industry, and agricultural activities around the city, has led to several environmental issues.

The Santa Barbara Channel is a portion of the Southern California Bight and separates the mainland of California from the northern Channel Islands. It is generally south of the city of Santa Barbara, and west of the Oxnard Plain in Ventura County.

It trends east–west, is approximately 130 kilometres (70 nmi) long and averages about 45 kilometres (24 nmi) across, becoming narrowest at its easternmost extremity where Anacapa Island is about 30 kilometres (16 nmi) from the mainland. During the last ice age, the four northern Channel Islands, including Santa Rosa Island, were conjoined into Santa Rosae, a single island that was only five miles (8 km) off the coast.