U-Pb geochronology of detrial zircons from the Snow Lake pendant, central Sierra Nevada-Implications for Late Jurassic-Early Cretaceous dextral strike-slip faulting

摘要

The Snow Lake pendant is underlain by a thick (>1500 m) sequence of predominantly quartzite, marble, and schist that has previously been correlated with miogeoclinal strata of the western Mojava Desert. In this study, U-Pb analyses of detrital zircons from the Snow Lake pendant have been conducted to test for possible correlations with strata of the Cordilleran miogeocline, as well as nearby rocks of the Roberts Mountains allochthon and the Shoo Fly Complex. Zircons from Snow Lake strata yield dominant age groups that strongly support correlation of Snow Lake strata with miogeoclinal strata in the Mojave Desert. This correlation provides additional support for previous suggestions that the Snow Lake pendant was displaced ～400 km northward along the Mojave-Snow Lake fault.