Early Mesozoic Paleotectonic-Paleogeographic Reconstruction of Southern Sierra Nevada Region

Abstract

A paleotectonic-paleogeographic reconstruction was based on structural, petrologic, and geochronologic studies of pre-Sierra Nevada batholith framework rocks exposed between the San Joaquin River and the Garlock fault. Most available fossil data from roof pendants of this region indicate Late Triassic to Early Jurassic ages. An additional fossil locality from the western wall rocks yields a Late Permian Tethyan fauna. This is a maximum age for the enclosing rocks, for the fossils are in a limestone olistolith. As yet there is no sign of Paleozoic strata in the region except perhaps along the eastern Sierran crest in small metamorphic septa, and in the western foothills where ophiolitic rocks are present.