Geochronologic and geochemical data from Mesozoic rocks in the Black Mountain area northeast of Victorville, San Bernardino County, California

We present geochronologic and geochemical data for Mesozoic rocks in the Black Mountain area northeast of Victorville, California, to supplement previous geologic mapping. These data, together with previously published results, limit the depositional age of the sedimentary Fairview Valley Formation to Early Jurassic, refine the ages and chemical compositions of selected units in the overlying Jurassic Sidewinder Volcanics and of related intrusive units, and limit the age of some post-Sidewinder faulting in the Black Mountain area to a brief interval in the Late Jurassic. The new information contributes to a more complete understanding of the Mesozoic magmatic and tectonic evolution of the western Mojave Desert and surrounding regions.