GEOCHEMICAL AND IN SITU GEOCHRONOLOGICAL ANALYSES OF CAMBRIAN RHYOLITES IN THE WICHITA MOUNTAINS, SW OKLAHOMA

The Wichita Mountain range in southwestern Oklahoma has traditionally been interpreted to be formed due to a failed continental rift, or aulacogen. However, there have been interpretations that the Wichita Mountains, or more precisely, the Wichita Igneous Province (WIP), are not the result of a failed rift, but formed by alternate processes such as magmatic activity during transform faulting. Several of the magmas in the WIP produced rhyolites; these rocks have been studied from a stratigraphic and geochemical perspective by several workers, but are still poorly understood due to several factors. Here, we present preliminary O₂ and H₂O fugacity and crystallization temperature estimates of the Carlton Rhyolite group along with compiled geochemical data from the literature in an attempt to characterize intensive properties of early felsic magmas that formed within the WIP. Additionally, we present preliminary in situ zircon U-Pb dates from Carlton Rhyolite thin sections obtained from EPMA analysis.