Chasing Gold, Geysers and Geothermal Power With Carolina Muñoz-Saez (Courtesy Carolina Muñoz-Saez) Geologist Carolina Muñoz-Saez is in the business of hydrothermal systems. Her specialty: studying natural plumbing networks that circulate hot water underground, and occasionally erupt above it. These drive the geysers and hot springs of Yellowstone National Park. In other locations, they provide energy for electricity generation or heating. Some host unique microbial life forms. And, under the right conditions, circulating waters may pick up gold, copper or other valuable commodities from surrounding rocks, and concentrate them; many of the world’s most productive mines are the giant dried-up remains of onetime hydrothermal systems.