The Stone Cabin Formation, Nevada, USA: Geochemical and Isotopic Indicators of Magma Sources and Crustal Influence in an Eocene Caldera System

Abstract

The 35.8 Ma Stone Cabin Formation (SCF) ignimbrites and related Eocene volcanic rocks of this study are located in eastern Nevada within the Central Nevada Volcanic Field. The SCF is a part of the mid-Cenozoic, subduction-related, primarily intermediate to silicic volcanic event termed the Ignimbrite Flareup. This project aims to determine the magma source or sources of the SCF and determine the existence/extent of crustal contamination during petrogenesis using whole-rock major element, trace element, and Pb-Sr-Nd-Hf isotopic analysis. The source of SCF ignimbrites is the White River caldera southwest of Ely, NV. The caldera includes SCF intracaldera tuffs, low-Si to high-Si rhyolite lavas, and andesite lava flows.