Beatty Mountain Mining District, Goose Creek Mountains, Box Elder County, Utah, USAi

Regional Level Types
Beatty Mountain Mining District	Mining District
Goose Creek Mountains	Mountain Range
Box Elder County	County
Utah	State
USA	Country

The Beatty Mountain district is in the southern Goose Creek Mountains along the Utah-Nevada border in westernmost Box Elder County, roughly 100 mi west of Brigham City. The area has no known mines or historical prospects and no history of production. However, the Beatty Mountain district has been explored for Au by major mining companies intermittently for roughly the last three decades.
The Goose Creek Mountains are a structurally complex area just off the western flank of the Albion-Raft River-Grouse Creek metamorphic core complex in the Basin and Range Province. Geologically, the Beatty Mountain district has Lower to Middle Permian sedimentary strata cut by a series of imbricate low-angle detachment faults and is unconformably overlain by Miocene Salt Lake Formation sedimentary rocks and volcanics (Miller and others, 2012). The Permian strata are mostly members of the Park City Group, principally the Murdock Mountain Formation and the Phosphoria Formation. The Salt Lake Formation consists of thousands of feet of middle Miocene conglomerate and limestone overlain by about a thousand feet of middle to late Miocene tuffs and rhyolites. The volcanics are porphyritic rhyolite tuff and flows belonging to the Rhyolite of Granite Creek, about 13 Ma (Miller and others, 2012).
Mineralization in the Beatty Mountain district is likely related to the intrusion of the Rhyolite of Granite Creek. Prospects in adjoining parts of Nevada include quartz-calcite-adularia Au veins and hot springs Au mineralization. The area of most intense mineralization in Utah is south of Beatty Mountain along Straight Fork and is hosted in the Murdock Mountain Formation of the Park City Group. The Murdock Mountain Formation consists primarily of chert, limestone, and sandstone. The Au-Hg mineralization is associated with jasperoids and “punky” decalcification along Straight Fork. This mineralization is thought to have affinities to sedimentary rock-hosted Au-Ag deposits (USGS Model 26a).