TAPADO CANYON. Tapado Canyon, a valley with an intermittent stream, rises immediately south of Elephant Mountain in southern Presidio County (at 29°27' N, 104°00' W) and runs southwest for eight miles to its mouth on the Rio Grande, four miles below Domingo (at 29°22' N, 104°05' W). Its course crosses an area of Tertiary sedimentary and volcanic materials and terminates on a conglomerate of sandstone, tuff, and igneous rock. The soils in the area are generally light reddish-brown to brown sands and clay loams, often rough and stony. The vegetation consists primarily of sparse desert shrubs. Tapado is Spanish for "buried treasure."