Warm springs and wells are located at the northwestern corner of the East Range in Secs. 21, 27, 28, T35N, R36E (Cohen, 1962c; 1964). These springs are along the extension of a range-boundary fault that is believed to cross U.S. Highway I-80 near the center of Sec. 28, according to geophysical evidence (Cartwright and others, 1964). The springs are about 28-29°C and high in boron. Water wells down-gradient from the springs also contain 2-15 ppm boron (Cohen, 1964). A warm water well (30.6°C) is also reported from NE¼ Sec. 25, T35N, R36E (Ron Deichman, written commun., 1990), over 3 km east of the projected fault. Two temperature-gradient drill holes were drilled in the area in 1981 by Phillips Petroleum Co. One reported a bottom hole temperature of 57.7ºC at 116 m (GeothermEx, 2004).
The East Range fault described above is believed to intersect a buried northwest-trending fault which has been extended southward from the Krum Hills (figure). These faults are projected on the basis of geophysical evidence plus the presence of thermal water in springs and wells along the fault. Also, the alluvial units are altered in the vicinity of the faults, and spring deposits are present at several areas. These spring deposits consist of both siliceous sinter and travertine (Cohen, 1962b). The deposit in Sec. 33 is at the approximate maximum level of Pleistocene Lake Lahontan, and is possibly related. In that case, the deposit would be younger than about 50,000 years. White (1955a) describes the travertine at one spring terrace (probably in NE¼ NW¼ Sec. 33, T35N, R36E) as being light brown and very porous. One sample contained 9% Mn and 0.3% WO3. The present spring is not depositing travertine.
Tungsten-bearing manganese veins in E½ SE¼ Sec. 5, T34N, R36E are along the west border of the East Range, and near the East Range fault. This property has been called the Victory Lode, and is located just inside Pershing County, but is included with this Humboldt County description because of its possible relation to the fault. The veins consist largely of calcite with films of manganese and iron oxides. Other gangue minerals are quartz, chalcedony, and gypsum. R.J. Roberts (quoted in White, 1955a), believes that these veins are the "roots" of spring deposits now removed by erosion. They are no doubt older than the travertine deposits to the north, but are probably genetically related (White, 1955a).