Hydrogeochemical and Stream Sediment Reconnaissance Basic Data Report for Las Vegas NTMS Quadrangle,Arizona,California and Nevada.

摘要

This report presents the results of the geochemical reconnaissance sampling in the Las Vegas 1exp 0 x 2exp 0quadrangle of the National Topographic Map Series (NTMS). Wet and dry sediment samples were collected throughout the 18,770-km exp 2arid to semiarid area and water samples at available streams,springs,and wells. Neutron activation analyses of uranium and trace elements and other measurements made in the field and laboratory are presented in tabular hardcopy and microfiche format. The report includes six full size overlays for use with the Las Vegas NTMS 1:250,000quadrangle. Water sampling sites,water-sample uranium concentrations,water-sample conductivity,sediment sampling sites,and sediment-sample total uranium and thorium concentrations are shown on separate overlays. General and structural descriptions of the area are presented and the known uranium occurrences on this quadrangle are delineated. High uranium concentrations in sediment were very sparse on the Las Vegas quadrangle. With the exception of a few isolated samples,the highest uranium concentrations were associated with Colorado plateau rocks. (ERA citation 04:012533)