Filters: Tags: electron microprobe (X)10 results (7ms)
U-Pb age determinations of uraninite by electron microprobe analyses of ore samples from two solution-collapse breccia pipe uranium deposits, Grand Canyon region, northwest Arizona, USA
This data release compiles the electron microprobe spot analyses of U, Th, and Pb concentrations in uraninite (U oxide) particles, and corresponding calculated age determinations, measured in samples of ore from two uranium-copper breccia pipe ore bodies, the Canyon (Pinyon Plain) and Hack II deposits. The U-rich samples that were analyzed typify the deposits hosted by solution-collapse breccia pipes in the Grand Canyon region of northwestern Arizona. Applying procedures outlined by Bowles (1990), the U, Pb, and Th measurements from each spot analysis were used to calculate a model age for the formation of each uraninite particle. The U, Pb, and Th analyses and calculated age determinations are provided as additional...
Data Dictionary for Electron Microprobe Data Collected with Probe for EPMA Software Package Developed by Probe Software
This data dictionary describes most of the possible output options given in the Probe for EPMA software package developed by Probe Software. Examples of the data output options include sample identification, analytical conditions, elemental weight percents, atomic percents, detection limits, and stage coordinates. Many more options are available and the data that is output will depend upon the end use.
Electron microprobe geochemistry of apatite crystals in the iron oxide-apatite ores of the Adirondack Mountains, New York, 2016-2017
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...
Table of electron probe microanalyses of native copper and sulfide minerals from the White Pine sediment-hosted copper deposit, Michigan
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...
Tables of electron probe microanalyses from the Copperwood sediment-hosted stratiform copper deposit, Michigan, USA
This data release provides electron microprobe analyses of ore minerals from the Copperwood sediment-hosted stratiform copper deposit in the Upper Peninsula of Michigan. The minerals include bornite, chalcocite, native copper, native silver, and pyrite. Minerals were analyzed for Ag, As, Co, Cu, Fe, Hg, Ni, Pb, S, Sb, and Zn. Results with acceptable totals that lie between 98.5 and 101.5% show that these minerals are stoichiometric, with very limited substitution of other elements. The Copperwood copper deposit is a sediment-hosted stratiform copper deposit in the Presque Isle Syncline of the Upper Peninsula of Michigan. The Lower Copper Bearing Sequence has a 2018 mineral resource estimate of 42.2 million metric...
Melt inclusion and mineral geochemical analyses supporting the evaluation of petrogenesis, degassing, and metallogenic potential of mid-Cenozoic rhyolite magmas in northern Nevada, USA
This data release presents geochemical analyses of silicate melt inclusions, host quartz phenocrysts, and biotite phenocrysts in samples collected by the U.S. Geological Survey (USGS) from mid-Cenozoic rhyolitic rocks from northern Nevada. Igneous intrusions and volcanic rocks in this study encompass nineteen rhyolitic samples from five magmatic centers across northeastern Nevada. Rhyolites were emplaced throughout northeastern Nevada over about an 8 million year timespan (41–33 mega-annum) in a variety of eruptive styles and volumes, ranging from meter-wide dikes to caldera-forming ignimbrites, and were roughly contemporaneous with regional ore deposition. Samples were prepared for petrographic and scanning electron...
Geochemical data supporting a comparison of apatite between regional magmatism and the Pea Ridge Iron Oxide-Apatite-Rare Earth Element (IOA-REE) and Boss Iron Oxide-Copper-Cobalt-Gold-REE Deposits (IOCG) deposits, southeastern Missouri, USA
This data release presents high-spatial resolution geochemical analyses collected from Mesoproterozoic apatite crystals in igneous rocks from the St. Francois Mountains terrane and coeval ore rocks from the Pea Ridge iron oxide-apatite-rare earth element (IOA-REE) and Boss iron oxide-copper-gold (IOCG) deposits. These deposits are located in the southeast Missouri iron metallogenic province. These data support a journal article entitled, “Apatite trace element geochemistry and cathodoluminescent textures—A comparison between regional magmatism and the Pea Ridge IOA-REE and Boss IOCG deposits, southeastern Missouri iron metallogenic province, USA” by Celestine N. Mercer, Kathryn E. Watts, and Juliane Gross, that...
Electron Probe Microanalyses of apatite, rutile, and titanite from stream sediment and rock samples in the eastern Tanacross quadrangle, eastern Alaska
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,...
Electron microprobe analyses of hydrothermal muscovite crystals from gold-bearing quartz veins of the Klamath Mountains, California, 2014 and 2019 (ver. 1.1, June 2022)
This data release provides geochemical results of in situ electron probe microanalyses of hydrothermal muscovite associated with gold-bearing quartz veins from the Klamath Mountains, California. Samples were collected from eight different mines in the summer of 2013 and electron probe microanalyses were carried out May 27, 2014 and November 12, 2019.
Table of Electron Probe Microanalyses of Cassiterite from the Sullivan Pb-Zn-Ag Deposit, British Columbia
This dataset contains results from electron microprobe analyses of cassiterite from the Sullivan Pb-Zn-Ag deposit, British Columbia. These data were collected from two samples and may not reflect the overall variability present at the deposit. An ASCII text file of results is provided in comma-separated by value (csv) format. The file has the name “2019-07-09_Sullivan_Cassiterite”.