Postdoctoral Fellowship: EAR-PF: Understanding the Mechanics of Caldera Collapse Eruptions

Crozier, Joshua Allen, Moffett Field CA

Investigators

Abstract

Many volcanic eruptions involve caldera collapse, where a section of rock overlying a magma reservoir drops downward as an eruption progresses. Caldera collapse has occurred during the largest explosive eruptions in Earth’s history, but also during multiple eruptions in the past few decades. However, the factors controlling the time evolution of caldera collapse eruptions are poorly understood, which limits our ability to infer past eruptive conditions and make forecasts about ongoing or future eruptions. This project will develop caldera collapse simulations that include both earthquakes and magma dynamics, then compare simulations to various types of geologic data and volcano monitoring data. The project will quantify controls on caldera collapse eruption evolution and constrain important rock and magma system properties at several volcanoes, including Kīlauea in Hawaii. In addition to communicating results to volcano observatories, immersive animations and sonifications of the 2018 Kīlauea eruption will be produced for broader outreach. This project will study temporal dynamics of caldera collapse in both mafic and silicic eruptions. It will examine what controls eruption episodicity, and how this influences eruptive regimes and overall eruption volume and duration. This project will develop 3D numerical models that couple elastic and multiphase fluid mechanics, including earthquake physics and magma ascent dynamics. Simulations will be compared to geophysical and video data from recent mafic eruptions to constrain ring fault geometry and frictional properties. Simulations will also be compared to geologic and petrologic data from older silicic eruptions to examine how different proposed pre-eruptive reservoir conditions, including magma stratification and melt lens distributions, influence eruptions and the resulting deposits. 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.