NSF Award
2404029
This project will collect electromagnetic data at Brothers volcano, the best-studied submarine volcano in the world. These data will image the inner workings of an active volcano and map fluid flow paths. Fluid flow leads to the precipitation of minerals that form heavy metal deposits. New and existing data will be integrated to estimate the amount of heavy metals deposited at this volcano. Broader impacts include engaging the public through a research cruise blog; training a researcher in electromagnetic methods and geophysical interpretation; presenting results in classrooms, at conferences, and to stakeholders; and building international partnerships through collaboration with colleagues from the US, UK, New Zealand, Germany, Italy, and Switzerland. This is a project jointly funded by the National Science Foundation’s Directorate for Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award recommendation, each Agency funds the proportion of the budget that supports scientists at institutions in their respective countries.<br/><br/>Hydrothermal fluid circulation is the key mechanism of chemical and thermal exchange between the solid Earth and oceans and plays an important role in volcanic hazard. Ocean drilling has provided important insights into the upper few hundred meters of submarine hydrothermal systems, but deeper fluid pathways and their relationship with the underlying magmatic heat source are poorly known. Partial melts, hydrothermal fluids and associated mineral deposits all have distinctive electrical resistivity. This project will conduct a unique electromagnetic experiment to image for the first time in three dimensions the inner workings of the hydrothermal system and underlying magma storage region of Brothers volcano, an active arc volcano. Brothers volcano is part of the Tonga-Kermadec arc and is the best-studied submarine arc volcano globally. During this experiment, two 3D grids of active-source electromagnetic data collected at Brothers volcano will be used to constrain the hydrothermal fluid flow paths and architecture of the magma plumbing system. The imaging will achieve a resolution that is impossible at terrestrial arc volcanoes and will reach depths beyond those accessible by drilling. The 3D resistivity models generated from this dataset will be integrated with seismic, magnetic, heat flow, and coring data to improve structural resolution of the subsurface and to more accurately apply empirical relationships to estimate porosity, permeability, sulfide mineralization, and melt fraction of the magma-hydrothermal systems.<br/><br/>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.
