Five or six hot springs and spring systems are located along the margins of the Sulphur Spring Range in southeastern Eureka County, these springs described below are Bruffeys Hot Springs, Shipley Hot Springs, Carlotti Ranch Springs, Siri Ranch Spring, Flynn Ranch Springs, and possibly Sulfur Springs. A prominent fault bounds the Sulphur Springs Range along the west side of Diamond Valley and cuts through the range near Bruffey Canyon; it is apparently coincident with Bruffeys Hot Springs and Carlotti Ranch Springs along the east side of Pine Valley.
Bruffeys Hot Springs (formerly Mineral Hill Hot Springs), located in Sec. 14, T27N, R52E, have the highest temperatures of those along the trace of the fault. Temperatures are up to 66.7°C (Stearns and others, 1937), with a flow rate of 189 L/min (Reed and others, 1982, p. 40), and travertine occurs as prominent terraces. Six springs occur along a north-south fault of large displacement. The old travertine deposits here contain barite and fluorite, although the travertine presently being deposited is devoid of barite and fluorite (White,1955a). Oil and gas seeps are reported from the hot springs and vicinity (Garside and others, 1988, p. 30). At the Blackburn Oil Field, about 6 km to the northwest, the reservoir temperature is about 120°C at 1,260 m, in agreement with chemical geothermometer calculations (Goff and others, 1994).