Evaluating the causes of protracted explosive eruptions at Kilauea Volcano, Hawaii

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In the past 2,500 years, Kilauea Volcano (Hawaii) has had several centuries-long periods of dominantly explosive eruptive activity. After the after the 2018 caldera collapse, there were large lava flow outpourings at the East Rift Zone and a shift to explosive behavior. Researchers see the connection between those events as a trend that occurred in the past and may repeat. Work will include olivine geochemistry and diffusion chronometry to address three questions: 1) what is the role crustal versus mantle inputs in the transition to an explosive phase at Kilauea? 2) what is the effect of caldera collapse on the system on the plumbing feeding subsequent eruptions? 3) over what time scale does the transition from effusive to dominantly explosive eruptions take place? This project will provide an early career researcher with experience managing and running a large research project at an academic institution. Exercises will be developed on effusive vs. explosive eruptions for use during K-12 classroom sessions through the non-profit program Skype a Scientist, bringing STEM enrichment to schools across the country. This project will emphasize advancing scientific understanding of explosive volcanic eruptions to better evaluate hazard potentials for this type of eruptive behavior. Finally, these data will inform on pre-eruptive warning signs for future explosive eruptions in Hawaii, further developing the potential for geochemical methods to be used as monitoring and predictive tools. Repeated patterns in mineral and lava geochemistry from 1500 C.E. to present suggest that explosive periods are controlled by fundamentally different crustal processes than effusive periods and are intimately linked to cycles of basaltic caldera collapse. This project will investigate the causes of protracted explosive volcanism at Kilauea by examining the geochemistry of lavas and tephra from the Uwekahuna Ash, a 1200-year period of explosive activity. Mineral compositions and zoning patterns will be used to determine the timescales of magma mixing and storage. Glass major and trace element geochemistry will be used to characterize mantle source composition, partial melting, and the flux of magma into the volcanic system. Combined with existing datasets for eruptions spanning 1500-present day, these analyses will be used to look for – and evaluate the causes of – repeating patterns in the geochemical record over the past 2,500 years.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.