Determining the Lifespan of Hydrothermal Systems Using Thermochronology and Thermal Modeling
Scott Jess, Eva Enkelmann, Stephen E. Grasby, Kelley Fraser
Abstract
Abstract The drive toward lower carbon emissions has led to a rise in global geothermal exploration. Hot springs are key exploration targets as they reflect active advection of thermal fluids derived from heating of meteoric waters circulating through the upper crust. However, establishing the timing of hot spring formation and the longevity of systems remain key knowledge gaps in our understanding of geothermal systems, such as how and when hydrogeologic conditions enable deep groundwater circulation to initiate. In this study, we demonstrate that a combination of multiple low‐temperature thermochronometers and finite element modeling can be used to determine the lifespan of the Canoe River Hot Springs flow system, British Columbia, Canada. Rocks adjacent to the hot spring show evidence of reheating because of thermal fluids, an effect absent in more distant samples. Hydrothermal modeling of both constant and episodic flow scenarios over different timescales highlights that the hot spring likely began flowing between 4 and 6 Ma. This timing of flow onset implies the hot spring’s formation may be linked to partial melting at the base of the crust, associated with nearby volcanic activity that has increased heat flow across the region in the late Cenozoic. These results have significant implications for the exploration of geothermal energy systems and for understanding the conditions required to form hot springs across British Columbia.