DETERMINING THE VOLUMES, POROSITIES, AND AVAILABLE ENERGY OF SELECTED RESERVOIRS UTILIZING GIS METHODS: WILLISTON BASIN, NORTH DAKOTA

The volume of rock containing geothermal fluids with temperatures above 90° C in the Williston Basin is approximately 49,920 km³, and the extractable energy contained in these fluids is approximately 161 x 10⁶ MW. The data used for our calculations includes: bottom-hole temperatures (BHT), formation thickness, and porosity. The data from a total of 10,952 wells with a BHT over 90°C were imported into ArcGIS, buffered to 1.6 km from centroid, and outlined with a polygon feature to define a surface area. We used average formation thicknesses to determine approximate volumes for ten reservoirs, which we grouped by system from Pennsylvanian to Cambrian. We obtained porosity information of the Pennsylvanian, Mississippian, Devonian, Silurian, Ordovician and Cambrian formations from well logs. We calculated the available energy assuming that: 1/1000 of the water volume can be extracted each year, a binary cycle power plant will achieve a 40 degree drop in water temperature during electrical power production, and that the efficiency of the binary power plant utilized is 12%.