Petroleum Potential of California Central Coast Ranges
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Thomas A. Baldwin, E. M. Adams, W. J. Classen, C. M. Cross, R. K. Cross, E. A. Gribi, R. R. Thorup, 1971. "Petroleum Potential of California Central Coast Ranges", Future Petroleum Provinces of the United States—Their Geology and Potential, Volumes 1 & 2, Ira H. Cram
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Abstract
The Central Coast Ranges include the Salinas and Cuyama-Carrizo basins and the Santa Cruz Mountains area. Unusual complications of structure and stratigraphy throughout the region were caused by stresses resulting from the major fault systems (San Andreas and Nacimiento) at the boundaries. Different positions relative to these master faults and to stable granitic masses resulted in basins with three different structural and stratigraphic styles. Oily and organic shales compose a large part of the 4,500 cu mi (18,750 cu km) of Tertiary sedimentary rocks within the province. Permeable carrier beds and reservoir sandstohes form a smaller percentage of the total fill than they do in the more prolific producing areas of the state. Locally favorable conditions located by persistent drilling have resulted in the discovery of 2.5 million bbl of original oil in place. The oil-generating capacity of the province far exceeds the discovered reserves. A large proportion of the oil generated probably either has remained in source position, has been dissipated to overlying seas during primary compaction, or , has been lost because of exposure due to later tectonic episodes. However, it is probable that reserves roughly equivalent to those already developed will be discovered if an economic climate favorable to multiple wildcat drilling by small operators can be assured.
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Future Petroleum Provinces of the United States—Their Geology and Potential, Volumes 1 & 2

The geology of the entire United States, including the continental shelf and slope, was studied by petroleum geologists to determine its petroleum potential. Prospective areas of the 11 regions were assessed qualitatively and, usually, quantitatively.
The prospective basinal area covers approximately 3.2 million sq mi (statute; 8.3 million sq km) and contains approximately 6 million cu mi (25 million cu km) of sedimentary rock above basement or 30,000 ft (9,144 m). Other less prospective areas are, in the aggregate, large.
The prospective area has not been explored adequately. Many high-potential areas are indicated by the geology and extent of exploration, particularly in parts of Alaska, California, Colorado, Louisiana, Mississippi, Montana, New Mexico, North Dakota, Oklahoma, Texas, Utah, and Wyoming, and in parts of the offshore of Alaska, California, Louisiana, and Texas. The prospective Atlantic, Florida, and Alaska continental shelves, and the entire continental slope, barely have been touched by drilling, and other prospective areas and depths on land and the continental shelf remain largely unexplored.
Estimates of potential crude oil reserves of the basinal area only, exclusive of known reserves, range from 227 to 436 billion bbl of original oil in place. The potential probably exceeds the mean of 332 billion bbl. Approximately 32 percent of the oil in place would be recoverable at known rates of recovery. Ultimately, the rate of recovery may reach 60 percent.
Estimates of potential natural gas reserves exclusive of known reserves range from 595 to 1,227 trillion cu ft of recoverable natural gas. The gas potential also probably exceeds the mean of 911 trillion cu ft.
The ultimate petroleum potential of the United States, including known reserves, may exceed 432 billion bbl of crude oil, 1,543 trillion cu ft of natural gas, and 49 billion bbl of natural gas liquids.
Finding and developing the large petroleum potential will require a great amount of drilling because a significant percentage of the visualized undiscovered crude oil and natural gas is in stratigraphic traps, combination stratigraphic and structural traps, reefs, and complex structural situations. Estimates of future domestic demand call for accelerated exploration. To the extent that policies of industry and government militate against accelerated exploration, particularly drilling, a high percentage of the petroleum resources of the United States will not be reduced to possession.