'United States Department of the Interior, Geological Survey. Open-file report 84-130, plate 2.' 'Prepared in cooperation with the Clark County Department of Comprehensive Planning.' 'Geology by R.W. Plume, 1981.' Scale [ca. 1:31,680. 1 in.=approx. .5 miles]. . Series: Open-file report (Geological Survey (U.S.)) 84-130. Originally published as plate 2 of Ground-water conditions in Las Vegas .Valley, Clark County, Nevada. Part I. Hydrogeologic framework / by Russell W. Plume, published by the U.S. Geological Survey in 1984 as Open-file report 84-130. "Prepared in cooperation with the Clark County Department of Comprehensive Planning."