The West Edison oil field is on the east side of the San Joaquin Valley about 9 miles southeast of Bakersfield. Oil occurs principally in the non-marine Chanac formation (Pliocene-Miocene) and and marine Santa Margarita sand (upper Miocene), and minor production is developed from marine Nozu sand (middle Miocene) and Olcese(?) sand (lower Miocene). The total thickness of strata overlying basement varies from 4,000 to 6,500 feet, and average depth of wells is about 4,000 feet. A diagram based on unusually good well control shows the transitional relationships between the Chanac and Santa Margarita formations. Pre-Santa Margarita stratigraphy and structure are not clearly understood because of the paucity of data, but stratigraphic cross sections are presented in an attempt to portray possible conditions during that time.

The field is on a general regional homocline dipping southwest, and oil accumulation is largely due to normal faulting with partial help from lensing sands. Some of the larger pools in the field are trapped on the down-thrown side of normal faults.

The field was discovered in 1935 and has had five periods of activity as a result of discovery of new zones and new fault blocks. There are now 1,300 acres productive from 180 wells. Total production is more than 8 million barrels or 6,200 barrels per acre, and 1951 showed the highest annual production in the field's history, 1,400,000 barrels. Current production is 4,200 barrels per day, or an average of 23 barrels per day per well.

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