Numerical assessment of the geothermal resource potential of the Charlevoix meteorite impact crater, Canada

Abstract

Geothermal targets may be found in naturally fractured rocks of meteorite impact craters hosting low temperature resources. We therefore conducted a study with the objective of evaluating the geothermal potential of the 400 million year old Charlevoix impact crater in Quebec (Canada). Finite element simulations of steady state groundwater flow and heat transfer were made based on field characterization that allowed for the evaluation of rock thermohydraulic properties. Simulations provided a definition of the temperature field in cross-sections of the crater up to 10 km depth. Results allowed quantification of the impact of the deep groundwater recharge, the rock thermal conductivity and the Earth heat flow on the temperature distribution at depth. The calculated geothermal gradient inside the Charlevoix crater reaches 31 °C km^-1 in the most favorable areas. The average temperature at 3 km depth was 70 °C inside the crater and was higher compared to outside the crater. This suggests greater potential for low-temperature geothermal direct use in the crater.