Mount Poso Oil Field

Discovered in 1926, it is the 21st largest field in California by total ultimate oil recovery, having a cumulative production of close to 300 million barrels (48,000,000 m3).

Source rocks are well-sorted medium grain marine sandstones of high porosity (around 35%).

Underneath the oil-bearing sedimentary formations, the basement granitic complex is of Jurassic age.

Oil from the field is heavy crude, and consistent between the different areas, ranging from API gravity of 13 to 16.

[6] In 1999, as the field appeared to be played out, they sold it to Nuevo Energy, the predecessor of Plains Exploration & Production (PXP).

This firm ran the field until they sold their portion of it to Vintage Production LLC, a subsidiary of Occidental Petroleum, in 2006.