Thermal analysis of the southern Powder River Basin, Wyoming

Temperature and geologic data from over 3000 oil and gas wells within a 180 km × 30 km area that transect across the southern Powder River Basin in Wyoming, U.S.A., were used to determine the present thermal regime of the basin. Three‐dimensional temperature fields within the transect, based on corrected bottomhole temperatures (BHTs) and other geologic information, were assessed using: (1) A laterally constant temperature gradient model in conjunction with an [Formula: see text] norm inversion method, and (2) a laterally variable temperature gradient model in conjunction with a stochastic inversion technique. The mean geothermal gradient in the transect is 29°C/km, but important lateral variations in the geothermal gradient exist. The average heat flow for the southern Powder River Basin is [Formula: see text] with systematic variations between [Formula: see text] and [Formula: see text] along the transect. Extremely high local heat flow (values up to [Formula: see text]) in the vicinity of the Teapot Dome and the Salt Creek Anticline and low heat flow of [Formula: see text] occurring locally near the northeast end of the transect are likely caused by groundwater movement.