A heat tracing experiment using cross-borehole time-lapse ERT

Abstract

Summary This study contributes to an ongoing project of geothermal heating/cooling system design for an office building in Quebec City, Canada. In this study, a heat tracing experiment using time-lapse cross-borehole ERT was performed. The time-lapse ERT inversion was conducted in order to image the spatiotemporal resistivity changes due to the heat injection. The inverted models were compared qualitatively to the pumping/injection rate log and temperature logs at different depths in the monitoring well. These comparisons demonstrate that the inversion results show the same trend as the temperature logs, notably they both clearly show the injection and the recovery phase of the experiment. Our results indicate that cross-borehole ERT could be used as an additional monitoring tool for heat injection tests.