“…In the Maricopa area and throughout much of central California, the Monterey Formation is unconformably overlain by the upper Miocene Santa Margarita Formation (Ryder and Thomson, 1989). On the west side of the Temblor Range, the Santa Margarita Formation is about 500 m thick (Ryder and Thomson, 1989, p. 54) and consists mostly of conglomerate and sandstone thought to have been derived from granitic, metamorphic, and volcanic rocks located west of the San Andreas Fault in the Gabilan Range, now displaced to the northwest by right-lateral slip along the San Andreas Fault (Huffman, 1972).…”