Preliminary Sedimentary Geothermal and Lithium Resource Assessments in the Great Salt Lake and Wendover Areas, Utah, USA

Abstract

The Basin and Range Province of the United States is an area of interest for geothermal power development due to the extended continental crust of the Basin and Range Province providing a tectonic mechanism to bring mantle heat close to the Earth’s surface. In addition, the thick accumulations of highly permeable Cenozoic sedimentary rocks that have accumulated in many of the basins may provide large pore volumes that at depth could be quite warm based on prospective geothermal gradients in some areas. The closed nature of many of the Basin and Range basins ensures that weathering products from igneous rocks (such as lithium and critical minerals) are trapped within the same pore volumes of water. This study examines the Great Salt Lake area (Utah, USA) extending as far west as Wendover for its potential to host stratiform geothermal resources as well as lithium and other critical minerals. Based on mapping by the US Geological Survey, three prospective basins with thick sedimentary accumulations were identified for resource assessment. The Wendover Graben was chosen because of high local geothermal gradients, it hosting active potash brine mining from both shallow and deep brines, lithium presence in produced brines, and local domestic direct use geothermal activity. Two larger basins under the Great Salt Lake were chosen for the presence of geothermal springs in the vicinity, presence of lithium in the Great Salt Lake water, and proximity to a large offtake for geothermal power (Salt Lake City). Preliminary in-place geothermal and lithium resource assessments were developed based on high, medium, and low values for porosity, lithium concentrations, and geothermal gradient. In the mid-case, these suggest approximately 10^10 MWh reservoir thermal energy and 8300 ktonnes of LiCO3-equivalent for the Wendover Graben, and for each of the two basins under Salt Lake approximately 6 x10^10 MWh reservoir thermal energy and 100,000 ktonnes LiCO3-equivalent. Recoverable values are likely lower. Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy's National Nuclear Security Administration. SAND2025-12854C