SEMINAR - Brandon Browne

Not-So-Simple Cinder Cone Plumbing Systems: Examples From the Sierra Nevada

Brandon Browne
Department of Geological Sciences
California State University Fullerton

April 22nd, 2009

Cinder cones situated in continental monogenetic volcanic fields are generally thought to erupt single magma batches over short periods of time. However, field mapping efforts combined with petrologic, geochemical, and thermobarometric analysis of erupted products from two unrelated volcanic fields in California (Red Cones, 5 km SW of Mammoth Mountain; and Golden Trout, 5 km SW of Mt Whitney) indicate pronounced differences in the eruption volumes and Pressure-Temperature crystallization histories of erupted basalts despite overall similarities in magma source. These findings suggest that magma plumbing systems and the mechanisms for magma supply at cinder cones are actually quite complex, and therefore require us to modify our perspectives on how they from as well as the types of geophysical signals they potentially yield before, during, and after eruptions.