A hot spring near Mosquito Ranch, in SEĽ NEĽ Sec. 6, T11N, R47E has a reported temperature of 35şC (Fiero, 1968). About 4.5 km to the north, a hot spring is also reported by Fiero in SEĽ SEĽ Sec. 24, T12N, R46E, and hot wells are shown in Secs. 19 and 20, T12N, R47E, on the Mosquito Creek 7.5-minute topographic map. A tufa mound and infrared thermal anomaly are reportedly associated with the Sec. 24 spring (Fiero, 1968). The hot springs and wells are apparently associated with a Holocene fault, the Central Monitor Valley fault (Sawyer, 1998).