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chlorite-muscovite schist, and actinolite-chlorite schist, underlies the

entire Sierra Pelona and is the oldest rock in the mapped area. Thin

beds of quartzite and limestone are present, as are talc-actinolite

bodie_s and quartz veins. The age of the schist is known to be pre-

Cretaceous, and is believed to be pre-Cambrian by many previous

workers in this region.

Granitic and gneissic rocks crop out to the east and south

of the Soledad basin. At least some of the gneisses represent the

Pelona schist that has been highly injected by granitic magmas. The

granitic rocks range in composition from quartz diorite and quartz

monzonite to nearly true granite, and are believed to be correlatives

of rocks of the Sierra Nevada batholith.

Andesite and basalt flows of the Vasquez series attain a

thickness of nearly 4,000 feet. These volcanic rocks are discussed in

connection with the Vasquez series.

Pelona schist

The Pelona schist appears in several widely separated areas

of southern California, including the Sierra Pelona (Hershey, 1902a,

pp. 274-277), Portal Ridge (Simpson, 1934, p. 318), the eastern San

Gabriel Mountains along the south side of the San Andreas fault from

Valyermo to San Bernardino (Noble, 1933, pp. 11-12), and in an

elongate area between the branches of the Garlock fault in the Tehachapi

Mountains (Wiese, 1950, pp. 12-15). All of the above areas lie in a