TY - RPRT TI - Age, geochemical composition, and distribution of Oligocene ignimbrites in the northern Sierra Nevada, California: Implications for landscape morphology, elevation, and drainage divide geography of the Nevadaplano AU - Elizabeth J. Cassel AU - Andrew T. Calvert AU - Stephan A. Graham PY - 2009 DO - 10.1080/00206810902880370 UR - https://pubs.usgs.gov/publication/70035191 ID - 70035191 ER -