Distribution of buried hydrothermal alteration deduced from high‐resolution magnetic surveys in Yellowstone National Park

A significant demagnetization of the subsurface, extending to depths of at least several hundred meters, has been identified in hydrothermal areas within Yellowstone National Park (YNP). This finding correlates closely with zones of intense hydrothermal activity and alteration, suggesting that magnetic surveys can effectively map buried hydrothermal systems. The study utilized high-resolution airborne and ground magnetic surveys, alongside measurements of rock magnetization from field samples and drill cores, to reveal the geometry and extent of subsurface alteration in three thermal areas: Firehole River, Smoke Jumper Hot Springs, and Norris Geyser Basin. Notably, a pronounced negative magnetic anomaly over Lone Star Geyser highlights substantial demagnetization linked to large-scale fluid flow.

Bouligand, C., Glen, J. M. G., & Blakely, R. J. (2014). Distribution of buried hydrothermal alteration deduced from high‐resolution magnetic surveys in Yellowstone National Park. Journal of Geophysical Research: Solid Earth, 119(4), 2595–2630. Portico. https://doi.org/10.1002/2013jb010802