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 sandstones 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 persis ent 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.