Collaborative Research: Beyond the big ones: Petrochronologic investigation of Quaternary small-volume volcanism in the Black Rock Desert, Utah

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

Utah has experienced dozens of volcanic eruptions over the last 3 million years. The chemical compositions of these lavas has varied, and eruptions have been both explosive and effusive. These differences in composition and eruptive style often have occurred within the small geographic area over narrow timespans. This work seeks to resolve the timing of eruptions and understand the processes associated with the magma bodies that ultimately produced such a wide variety of compositions. The project will provide opportunities for undergraduate students to participate in research, including sample collection, traveling to multiple laboratories, and presenting their work at international meetings. It will also provide training to K-12 educators in Utah; these will focus on volcanic processes and will be held in conjunction with the Utah Society for Environmental Education. Over the last decade, improved accuracy and precision of Ar/Ar dating coupled with zircon petrochronology (the combination of morphological, textural, geochemical, and geochronologic data) has allowed for improved understanding of the evolution of magma chambers prior to eruption, and connecting these processes to bimodal volcanic fields. Most of the recent petrochronology studies have focused on understanding melt extraction and differentiation trends in large-volume magmas or magmas within large silicic volcanic fields, both of which often result in super-eruptions or solidified batholiths. This project will expand the scope of petrochronologic applications by examining magmatic processes in small, monogenetic volcanic fields in central Utah, and by comparing those to the proposed magma dynamics that drive super-eruptions like those at Yellowstone. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.