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David T Adams

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This dataset is a collection of geochemical data on samples from the Stibnite-Yellow Pine district of Idaho. The datasets include: whole rock geochemistry; lead, strontium and neodymium isotope chemistry of sulfides and whole rock samples by isotope dilution-thermal-mass spectrometry (ID-TIMS); in situ sulfur isotope chemistry of sulfides by laser ablation-multi collector-inductively coupled-mass spectrometry (LA-MC-ICP-MS); electron microprobe (EMP) images, cathodoluminescence (CL) images and spectra, along with EMP and laser ablation-inductively coupled-mass spectrometry (LA-ICP-MS) trace element analysis of sulfides and quartz; and fluid inclusion microthermometry and raman. Samples were collected from the surface...
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The iron oxide-apatite (IOA) deposits near Mineville in the Adirondack Mountains, New York, have been of interest for their rich magnetite ore since the mid-1700s but have attracted renewed attention due to their potential as rare earth element (REE) resources (McKeown and Klemic, 1956; Lupulescu and others, 2016; Taylor and others, 2018). Apatite is the main REE-host and is found in variable concentrations within ore seams of the regional magnetite deposits. Some apatite crystals are unaltered, relatively homogenous, and inclusion-free, whereas other deposits contain heterogenous apatite with zones of abundant secondary mineral inclusions that were formed through metasomatic reactions with the apatite after initial...
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This data release provides electron microprobe geochemical data that was collected as part of a scoping study to evaluate whether unconventional critical element resources may be associated with sediment-hosted copper systems in the Midcontinent Rift. We report abundances of trace elements in native copper and sulfide minerals in 12 thin sections from samples of the Mesoproterozoic lower Nonesuch Formation that were collected from underground exposures in the White Pine deposit. Approximately 350 spots were analyzed for Cu, Pb, Zn, Fe, Ni, Co, As, Sb, Ag, Hg, and S. The electron microprobe data were collected by personnel of the Central Region Minerals Program in Denver, Colorado, for the U.S. Geological Survey...
Categories: Data; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Ag, Antimony, Arsenic, As, Central Region Minerals Program, All tags...
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The genetic origin of many gold deposits, including Pogo in Alaska, remains controversial with questions as to whether they formed due to magmatic-hydrothermal or metamorphic-hydrothermal fluids. Gaining a better understanding of the formation mechanisms for these deposits is critical for defining proper exploration criteria in gold-bearing regions and production within these deposits. Monazite are light rare earth (LREE)-bearing and xenotime are heavy rare earth (HREE)-bearing phosphate minerals that are found as alteration products in many gold deposits. In addition to their importance in geochronological investigations, their minor element chemistry may be used to differentiate between metamorphic, magmatic,...
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The exploration for porphyry deposits in some parts of Alaska may require unconventional exploration geochemical methods, depending on type of cover. The Taurus deposit and others in the region are mostly concealed by residual soils that in part include ash and loess, and therefore traditional stream sediment samples typically contain subdued geochemical signatures. Indicator mineral studies include collection of stream sediment samples and analysis using automated SEM mineralogical techniques. The presence of select minerals in the stream sediments may indicate mineralization. In addition, the chemistry of specific minerals may be used to distinguish a hydrothermal origin as opposed to others, and include apatite,...
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