The purpose of this project is to focus analytical work on the Central and Modern Volcanics of Seguam Island, using samples that were collected during a previous project which concentrated on the older Southern Volcanics. The PIs will be performing major, minor and REE analyses, microprobe and Nomarski characterization of the lavas, and Sr, Nd, and Pb isotopic analyses. The goal of the project is to understand the control which tectonic processes, such as extension and subduction of the Amlia fracture zone, exert upon the magmatic processes and the sources of arc lavas. Only rarely has the temporal evolution of magmatic processes been documented at individual island arc centers. By extending this study of Seguam to the Holocene, they will have a petrologic record that spans the entire period of volcanic activity which they can then evaluate in terms of changing tectonic environments over time.
