The Mesozoic continental margin of the southwestern United States was the site of major compression involving overthrusting and accretion of terranes to the active margin. However, the extent of Orogen-parallel strike-slip faulting is poorly constrained. Recent stratigraphic and structural data suggests the presence of a major (>500 km displacement) cryptic intrabatholithic fault of Early Cretaceous age in the Sierra Nevada. If confirmed, this discovery will have far reaching consequences, including the necessity to radically revise Jurassic and earlier paleogeography and tectonics of the western Cordillera. This project will critically test several specific predictions of this new model in an effort to establish the model's validity and to explore its impact on tectonic interpretations of the Mesozoic of western North America.
