HYDROMOX

Caldera volcanoes produce the largest explosive eruptions on the planet, yet the role fluids play in controlling eruption dynamics remains poorly understood and the mechanisms that control explosivity remain poorly constrained. Caldera eruptions can have global impacts, as shown by the unexpectedly violent 2022 Hunga Tonga-Hunga Ha’apai (HTHH) eruption that generated an atmospheric shockwave felt worldwide. Fundamental fluid interactions (hydrothermal/seawater/meteoric) with magma remain poorly understood, as any evidence is typically destroyed during the eruptive event, hence the lack of constraint on the impact of hydrothermal circulation is a major blind spot in our global understanding of volcanic behaviour and hazard forecasting. This project will characterise a case study marine caldera hydrothermal system and its connection to the underlying magma system in unprecedented detail, measure the effect of hydrothermal fluid flow on the physical properties of caldera rocks, quantify the importance of hydrothermal systems for magmatic outgassing, and parameterise models of the behaviour of hydrothermal systems during periods of volcanic unrest, providing an urgently needed step change in hazard forecasting by determining the controls on the role hydrothermal circulation plays in volcanic explosivity.

Contact: Eoghan Reeves