The Skunk Creek Site (CA-Tuo-1284), a seasonal exploitation site in the central Sierra Nevada, was tested in 1980, 1986, and 1987 by Michigan State University. This late prehistoric seasonal campsite includes eight bedrock mortar clusters with associated middens. About 2% of the site was excavated, and about 25% was surface-collected. The resulting collection included over 30,000 items, including more than 20,000 pieces of debitage (92% obsidian) and 7000 mammal bone fragments. Results suggest a Mariposa Phase (A.D. 1200-1800) seasonal occupation from late summer to mid-autumn, emphasizing obsidian acquisition by Miwok speakers who also processed surplus acorn and venison harvests for transport to winter base camps.