PERSISTENCE AND TRANSIENCE IN HYDROTHERMAL SYSTEMS RECORDED IN HOT SPRINGS, TRAVERTINE, AND SINTER

Hot springs have scientific and cultural significance in the American West. They are targets in early hydrothermal exploration and act as windows into the subsurface. They also provide unique habitats for sensitive wildlife and are iconic features in cultures across the globe. Unfortunately, the relationships among these interests can be contentious, as the drive to develop firm, low-carbon geothermal projects butts up against desires or mandates to conserve. Scientific and cultural investigations indicate an interesting dichotomy in hot spring systems, with spatiotemporal, hydrologic, and geochemical attributes that can be both persistent and ephemeral at different timescales and in different settings, making management of these features particularly challenging. In the central Great Basin, some travertine deposits show evidence that similar discharge temperatures and chemical signatures have persisted for more than 10,000 years, with much older extinct deposits at the same site suggesting cyclicity. Siliceous sinter deposits in the region appear more prone to large fluctuations in discharge conditions over shorter durations. I will address interactions among geologic structure, seismic activity, climate, and hydrology that can be observed in travertine and sinter at these sites and discuss novel methods of monitoring active hot springs as society navigates environmental, cultural, and renewable energy demands on these features.