NEW GEOLOGIC MAPPING OF THE SALT LAKE VALLEY

Over the last eight years (2012–2020) the Utah Geological Survey (UGS) has renewed its focus on mapping the geology of the Salt Lake Valley at 1:24,000 scale with the express purpose of providing highly detailed and accurate geologic maps to be used for derivative UGS geologic hazard maps of urban and rapidly developing areas. Our efforts utilized numerous traditional and nontraditional geologic tools and, combined with mapping efforts of the early 2000s, have resulted in nearly continuous detailed geologic map coverage of the valley. While mapping the area, new Quaternary faults were identified, mapped, and described, including the Nibley Park fault and the Foothill fault. Locations and ages of previously mapped Quaternary faults were scrutinized and revised where necessary. High-resolution topographic data derived from lidar helped identify and delineate a variety of geologic features, particularly Pleistocene and Quaternary deposits and landforms, including landslides. New mapping also revealed details regarding the flow path and deposition of deltas, rivers, and streams through the valley following the regression of Lake Bonneville, specifically those of the paleo-Jordan River.