The oil field is located in the northeastern extreme of the Ventura Basin Province, a petroleum-rich sedimentary basin with a long history of oil and gas production. Overall, the structure of the oil field is a plunging anticline oriented northwest to southeast, dipping to the southeast; most of the hydrocarbon accumulation is along the southwest flank of this structure,(1959) which resembles a southwest-dipping homocline. One stratigraphic unit, the Miocene-age Modelo Formation, contains oil and gas accumulations. To the northeast, the San Gabriel Fault closes the structure, trapping hydrocarbons with an approximate 500-foot offset, placing impermeable rock units adjacent to the petroleum-bearing Modelo formation. The other sides of the field are sealed stratrigraphically, specifically by permeability changes in the rock preventing hydrocarbon movement.
