1498 Big Bald Mt. text

The map area includes the Big Bald Mountain Quadrangle and the western part of Tognini Spring Quadrangle. It is located south of Overland Pass in the southern Ruby Mountains and the southern Maverick Springs Range, about 60 miles (100 km) south-southeast of Elko, Nevada, and about 50 miles (80 km) northwest of Ely, Nevada (figs. 1A, B). The map area, herein referred to as the Bald Mountain area, includes Big and Little Bald Mountains, Mooney Basin, and the southwest edge of the Maverick Springs Range (fig. 2). Mooney Basin extends about 20 miles (32 km) north from the southern part of Alligator Ridge into the map area, where, at the north end, it merges into Ruby Valley (fig. 2). The map area is on the southern extension of the Carlin gold trend and contains disseminated gold deposits of the Bald Mountain mining district. South of the map area and at the southern end of Mooney Basin, the Alligator Ridge and Yankee disseminated gold deposits were mined. For information on ore deposits, see Hitchborn and others (1996) and Nutt and others (2000). Previous geologic maps of the area include a reconnaissance map by Rigby (1960) and the White Pine County geologic map by Hose and Blake (1976). The map area is contiguous with the Alligator Ridge area to the south mapped by Nutt (2000). Isotopic ages of igneous samples located on this map are shown in table 1.