ACCURACY AND PRECISION IN CHARACTERIZATION OF AQUIFER GEOTHERMAL PROFILES

Geothermal profiles of aquifers are valuable for evaluating flow processes by modeling existing data or determining deviations from anticipated changes in temperature with depth. In aquifers with small changes in temperature, this is difficult as many environmental sampling tools are not precise temperature sampling tools. Determining accurate vertical geothermal profiles requires an understanding of the accuracy and precision of temperature measuring devices. In the Arbuckle-Simpson aquifer of central Oklahoma, temperatures vary by less than a degree Celsius across spatial and temporal ranges in springs and wells. We utilize well logging, transducer, temperature/level/conductivity probes, and precision platinum thermometers to evaluate the CAMARR (City of Ada Managed Aquifer Recharge Research) Site near Fittstown, OK. The results show small, but significant changes resulting in an inverted geothermal profile, with colder temperatures of the aquifer in depths of 300 meters or greater.