CAREER: Rethinking the Dynamics of Magma Storage and Eruption for Yellowstone’s Youngest Supereruption’

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Beneath Yellowstone National Park exists an active heat source which fuels the steaming springs and gushing geysers that draw more than 4 million visitors to the park every year. In the past, this heat source resulted in large-volume volcanic eruptions that created many of the rocks we see scattered across the landscape today. Because Yellowstone is a federally protected and active volcanic center, scientists have an obligation to understand the geologic history and possible hazards of such a massive volcanic system and to convey this information to the communities and people that visit each year. This project aims to systematically investigate the youngest supereruption, the Lava Creek Tuff, which produced the modern-day Yellowstone caldera. The questions to be addressed include: (1) how was magma positioned beneath the surface? (2) what may have triggered the magma to move to the surface? (3) where did magma erupt from? and (4) how long (days, weeks, years) did it take for all of these processes to occur? Throughout this project, the researchers will be training the next generation of geologists to develop their skills as scientists and communicators. Yellowstone provides an ideal setting to teach skills related to geologic mapping, critical thinking, and rock analysis, which is why this proposal is structured to provide eight undergraduate and three graduate students with summer mapping experiences, with an emphasis on recruiting students from underrepresented backgrounds. All students will be trained to be active stewards of Yellowstone science, writing blog articles and preparing presentations that communicate to the public the geology and monitoring of Yellowstone Volcano. The mechanisms and timescales by which large volumes of rhyolitic magma accumulate, are stored in the upper crust and are triggered to eruption remain fundamental questions in volcanology. The overall Research Objective of this proposal is to reevaluate the assemblage, storage and eruption dynamics of the youngest supereruption from the Yellowstone Volcanic Field (YVF), the Lava Creek Tuff (LCT; 0.63 Ma). This work was ignited by the 2018 discovery of two new ignimbrite units previously unrecognized (and currently spatially unconstrained) as belonging to the LCT. Additionally, hints of inter-depositional chemical variations within the LCT exist in the established literature but are currently poorly defined. The working hypothesis of this proposal is that the LCT eruption consisted of multiple magma bodies tapped differentially along the caldera boundary, comparable to what is inferred in the better-studied Huckleberry Ridge Tuff, the oldest (2.08 Ma) supereruption from the YVF. Through a combination of detailed field mapping, extensive whole rock, glass geochemistry and petrographic analysis, diffusion modeling and age dating, this project will rethink the makeup and progression of the youngest Yellowstone supereruption. The Educational Objective of this study is to leverage the proximity (1.5 hours) of Montana State University to one of the largest volcanic systems on Earth, using it as a field-based laboratory for training the next generation of geologists. This project presents numerous opportunities for practicing science communication in light of over 4 million tourists that visit the park each year. All students will be trained to be active stewards of Yellowstone science, writing blog articles and preparing public presentations that communicate the geology and monitoring efforts of Yellowstone Volcano.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.