Date of Award

Fall 2009

Project Type


Program or Major

Earth Sciences: Hydrology

Degree Name

Master of Science

First Advisor

J Matthew Davis


This research investigates thermal properties of fractured bedrock for the purpose of better understanding the sustainability of standing column well (SCW) geothermal heating systems. The three objectives are to quantify effective thermal conductivity and heat capacity of the fracture network; measure heat exchange between the fluid and the fractured surfaces; and estimate time of thermal breakthrough into a pumping well. Single and dipole well tests are performed to meet these objectives. Single well data is compared with an analytical heat flow model to estimate thermal conductivity and heat capacity. Dipole well data is compared to a model of the Kolditz (1995) modification of Gringarten and Sauty's (1975) thermal breakthrough curve. Thermal conductivity is estimated to be lower than the previously reported value by Roy et al. (1968). No thermal breakthrough is observed during the dipole test, however, modeling of theoretical SCW systems shows significant temperature changes over the long term.