Soil-gas samples were collected in two parallel traverses across the Dome fault zone of the Roosevelt Hot Springs Known Geothermal Resource Area. Gas chromatographic analyses of the samples showed anomalous concentrations of CS3 and COS east of the Dome fault; higher concentrations of CS2 and COS also occurred over an area in which the hydrothermal system is close to the surface. Measurement of these gases may be useful in exploration for new geothermal sources.