Statistical data are presented from a regional geochemical study of the Ajo 1° X 2° quadrangle exclusive of the Papago Indian Reservation, but including the extension of Organ Pipe Cactus National Monument into the Lukeville 1° X 2° quadrangle. Frequency distribution data from the analysis of stream-sediment and heavy-mineral-concentrate samples for 31 elements have broad ranges and for most elements have maxima well above normal. Elemental associations derived from correlation and R-mode factor analysis related to regional lithologic variation and for some associations suggest mineral-resource potential.
Paired rock and soil samples were collected at widely spaced locations in large segments of the porphyry-metal systems of the Montezuma district in central Colorado and of a northwestward extension of the Summitville district into Crater Creek in southern Colorado. The paired samples do not covary closely enough for one sample medium to proxy for the other. However, the areal distributions of elements in both rocks and soils in these two districts conform to alteration zoning as defined by mineralogy. Differing geochemical patterns of rocks and soils reflect species-dependent responses to weathering. Soils appear to be statistically enriched in ore elements and depleted in rock elements as compared to the matching rocks. These differences are largely artificial, owing to different methods of sample preparation and chemical analysis for rocks and for soils. The distributions of metals in soils delineate the occurrence of ore-metal minerals, mostly from vein deposits, whereas the distributions of metals in rocks conform to zones of pervasive hydrothermal alteration and to the distribution of varied mineral deposits among these zones. Rock and soil samples are equally useful, of comparable map resoluton, and complement one another as a basis for geochemically mapping these porphyry-metal systems.
A spectrochemical method for the determination of 10–1000 ppm tantalum and 20–1000 ppm tungsten in plutonium metal is described. Chemical separation by precipitation of the plutonium as insoluble plutonium trifluoride, centrifuging, and sampling the supernatant solution is well suited to the glove box operation necessary in handling plutonium. Excitation is by graphite spark; spectra are recorded photographically; and concentrations are determined by standard photometry practices using an emulsion calibration-analytical curve technique with a molybdenum internal standard.
Mines to conduct mineral surveys on certain areas to determine their mineral values, if any. Results must be made available to the public and be submitted to the President and the Congress. This report presents the results of a geochemical survey of the Goshute Peak Wilderness Study Area (NV-010-033),
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.