Talk title: "Geologic Hydrogen Exploration and Its Resource Potential in Iowa"

Geologic hydrogen is emerging as a possible primary energy resource with the potential to contribute to energy supply on century timescales. As global expansion of renewable energy and green hydrogen increases demand for critical minerals, naturally occurring hydrogen offers a complementary pathway that may reduce supply-chain pressures while leveraging established subsurface exploration expertise. A primary source of geologic hydrogen is serpentinization, in which iron-rich rocks react with water to generate hydrogen and associated contrasts in physical properties. These processes produce diagnostic geophysical signatures that can be detected using integrated geophysics such as magnetic, gravity, electrical, and seismic methods. We present an integrated framework for introducing geologic hydrogen systems and predicting their resource potential using multi-scale geophysical characterization. Airborne and ground-based geophysical data are combined with soil-gas measurements and core analyses across diverse geological settings, including Nebraska, Iowa, and the Midcontinent Rift. Results indicate that surface expressions such as fairy circles primarily reflect hydrogen leakage rather than viable drilling targets, emphasizing the need for regional-scale imaging to identify deeper source and accumulations. Existing petroleum and mining infrastructure can be directly adapted for hydrogen exploration, monitoring, and development. These results demonstrate that geophysics provides a critical foundation for forecasting geologic hydrogen prospectivity and supporting responsible resource development.