Suggested citation and version history for Beard, L.S., Anderson, R.E., Block, D.L., Bohannon, R.G., Brady, R.J., Castor, S.B., Duebendorfer, E.M., Faulds, J.E., Felger, T.J., Howard, K.A., Kuntz, M.A., and Williams, V.S., 2007, Preliminary geologic map of the Lake Mead 30' X 60' quadrangle, Clark County, Nevada, and Mohave County, Arizona: U.S. Geological Survey Open-File Report 2007-1010, 109 p., 3 plates, scale 1:100,000 [http://pubs.usgs.gov/of/2007/1010/]. Version 1.0 September 24, 2009 re-optimized the PDFs and set initial views larger April 5, 2007 Initial release online at http://pubs.usgs.gov/of/2007/1010/