Heather A Lowers
Heather Lowers is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 31
Geochemical data for the Elk Creek alkaline complex, southeast Nebraska Geochemical data for the Elk Creek alkaline complex, southeast Nebraska
This U.S. Geological Survey (USGS) data release contains analytical data from a suite of rock and mineral samples collected from drill core within the Elk Creek alkaline complex, southeast Nebraska. This complex hosts the Elk Creek carbonatite, a multilithologic carbonatite enriched in niobium, rare earth elements (REEs), scandium, and titanium. Mineralized carbonatites are the world's
Spectroscopy of Expanded Vermiculite Products and Insulation Spectroscopy of Expanded Vermiculite Products and Insulation
This dataset contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South...
Electron Probe Microanalyses of apatite, rutile, and titanite from stream sediment and rock samples in the eastern Tanacross quadrangle, eastern Alaska 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...
Table of Electron Probe Microanalyses of Native Copper and Sulfide Minerals from the White Pine Sediment-hosted Copper Deposit, Michigan 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...
Table of Electron Probe Microanalyses of Cassiterite from the Sullivan Pb-Zn-Ag Deposit, British Columbia 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".
Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA
This data release compiles the X-ray diffraction and electron microscopy analyses of drill core samples collected by the U.S. Geological Survey that were selected to typify the uranium-copper ore bodies of the Canyon deposit. The deposit is hosted by a solution-collapse breccia pipe, in which mineralization exists from about 650 to 2,100 ft (200 to 640 m) below the surface (Mathisen and...
Filter Total Items: 106
Hydrothermal monazite and xenotime chemistry as genetic discriminators for intrusion-related and orogenic gold deposits: Implications for an orogenic origin of the Pogo gold deposit, Alaska Hydrothermal monazite and xenotime chemistry as genetic discriminators for intrusion-related and orogenic gold deposits: Implications for an orogenic origin of the Pogo gold deposit, Alaska
Attempts to geochemically distinguish between metamorphic-hydrothermal systems that form orogenic gold deposits and both reduced and oxidized magmatic-hydrothermal systems using isotopes or metal associations have proven ambiguous, particularly for orogenic gold and reduced intrusion-related gold systems. The absence of conclusive geochemical discriminators and the overlap in geologic
Authors
Ryan D. Taylor, Garth E. Graham, Heather A. Lowers
Reconnaissance mineral and cathodoluminescence studies of gold occurrences in the Pogo-Black Mountain area, eastern interior Alaska, USA Reconnaissance mineral and cathodoluminescence studies of gold occurrences in the Pogo-Black Mountain area, eastern interior Alaska, USA
The Pogo Au deposit is the largest of a number of gold occurrences in eastern interior Alaska, that occur along a broad trend from west of Pogo to Black Mountain. Some of these occurrences are hosted in amphibolite facies gneisses and others in mid-Cretaceous igneous rocks that intruded the older metamorphic rocks. All occurrences contain arsenopyrite and pyrite. Whole rock geochemical...
Authors
Garth E. Graham, Erin E. Marsh, Heather A. Lowers, Ryan D. Taylor
The Mount Weld rare earth element deposit, Western Australia: A carbonatite-derived laterite The Mount Weld rare earth element deposit, Western Australia: A carbonatite-derived laterite
Carbonatite-hosted rare earth element (REE) deposits are the primary source of the world’s light REEs and have the potential to be a source of heavy REEs. The Mount Weld REE deposit in Western Australia is hosted in a lateritic sequence that reflects supergene enrichment of the underlying carbonatite complex. Similar to other carbonatite-related ore deposits, ore from Mount Weld displays...
Authors
Philip Verplanck, Heather A. Lowers, Adam Boehlke, Jay Michael Thompson, Ganesh Bhat, Cameron Mark Mercer
Hyperspectral cathodoluminescence and quantitative EPMA mapping of angrite northwest Africa 15507 Hyperspectral cathodoluminescence and quantitative EPMA mapping of angrite northwest Africa 15507
Angrite meteorites represent alkali depleted planetary crust of basaltic composition, and have both plutonic and volcanic lithologies. NWA 15507 is a microgabbroic specimen (mean grainsize ~1.4 mm) composed predominantly of zoned Al-Ti-augite, Ca-bearing olivine and anorthite together with accessory kirschsteinite, rhönite, hercynite, low-Ni kamacite, merrillite, magnetite and troilite...
Authors
Heather A. Lowers, Jay Michael Thompson, Paul K. Carpenter, Zoe Wilbur, Anthony Irving
Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA
The Proterozoic tectonic evolution of the south-western USA remains incompletely understood due to limited constraints on the timing and conditions of the tectono-metamorphic phases and depositional age of metasedimentary successions. We integrated multi-scale compositional mapping, petrologic modeling, and in situ geochronology to constrain pressure-temperature-time paths from samples...
Authors
Ian William Hillenbrand, Michael L. Williams, Karl E. Karlstrom, Amy K. Gilmer, Heather A. Lowers, Michael J. Jercinovic, Kaitlyn Suarez, Amanda Souders
Characterizing lung particulates using quantitative microscopy in coal miners with severe pneumoconiosis Characterizing lung particulates using quantitative microscopy in coal miners with severe pneumoconiosis
Context.— Current approaches for characterizing retained lung dust using pathologists' qualitative assessment or scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) have limitations. Objective.— To explore polarized light microscopy coupled with image-processing software, termed quantitative microscopy–particulate matter (QM-PM), as a tool to characterize in situ...
Authors
Jeremy T. Hua, Carlyne D. Cool, Heather A. Lowers, Leonard H. T. Go, Lauren M. Zell-Baran, Emily A. Sarver, Kirsten S. Almberg, Kathy D. Pang, Susan M. Majka, Angela D. Franko, Naseema I. Vorajee, Robert A. Cohen, Cecil S. Rose
Science and Products
Filter Total Items: 31
Geochemical data for the Elk Creek alkaline complex, southeast Nebraska Geochemical data for the Elk Creek alkaline complex, southeast Nebraska
This U.S. Geological Survey (USGS) data release contains analytical data from a suite of rock and mineral samples collected from drill core within the Elk Creek alkaline complex, southeast Nebraska. This complex hosts the Elk Creek carbonatite, a multilithologic carbonatite enriched in niobium, rare earth elements (REEs), scandium, and titanium. Mineralized carbonatites are the world's
Spectroscopy of Expanded Vermiculite Products and Insulation Spectroscopy of Expanded Vermiculite Products and Insulation
This dataset contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South...
Electron Probe Microanalyses of apatite, rutile, and titanite from stream sediment and rock samples in the eastern Tanacross quadrangle, eastern Alaska 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...
Table of Electron Probe Microanalyses of Native Copper and Sulfide Minerals from the White Pine Sediment-hosted Copper Deposit, Michigan 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...
Table of Electron Probe Microanalyses of Cassiterite from the Sullivan Pb-Zn-Ag Deposit, British Columbia 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".
Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA Mineralogical analyses of drill core samples from the Canyon uranium-copper deposit, a solution-collapse breccia pipe, Grand Canyon area, Coconino County, Arizona, USA
This data release compiles the X-ray diffraction and electron microscopy analyses of drill core samples collected by the U.S. Geological Survey that were selected to typify the uranium-copper ore bodies of the Canyon deposit. The deposit is hosted by a solution-collapse breccia pipe, in which mineralization exists from about 650 to 2,100 ft (200 to 640 m) below the surface (Mathisen and...
Filter Total Items: 106
Hydrothermal monazite and xenotime chemistry as genetic discriminators for intrusion-related and orogenic gold deposits: Implications for an orogenic origin of the Pogo gold deposit, Alaska Hydrothermal monazite and xenotime chemistry as genetic discriminators for intrusion-related and orogenic gold deposits: Implications for an orogenic origin of the Pogo gold deposit, Alaska
Attempts to geochemically distinguish between metamorphic-hydrothermal systems that form orogenic gold deposits and both reduced and oxidized magmatic-hydrothermal systems using isotopes or metal associations have proven ambiguous, particularly for orogenic gold and reduced intrusion-related gold systems. The absence of conclusive geochemical discriminators and the overlap in geologic
Authors
Ryan D. Taylor, Garth E. Graham, Heather A. Lowers
Reconnaissance mineral and cathodoluminescence studies of gold occurrences in the Pogo-Black Mountain area, eastern interior Alaska, USA Reconnaissance mineral and cathodoluminescence studies of gold occurrences in the Pogo-Black Mountain area, eastern interior Alaska, USA
The Pogo Au deposit is the largest of a number of gold occurrences in eastern interior Alaska, that occur along a broad trend from west of Pogo to Black Mountain. Some of these occurrences are hosted in amphibolite facies gneisses and others in mid-Cretaceous igneous rocks that intruded the older metamorphic rocks. All occurrences contain arsenopyrite and pyrite. Whole rock geochemical...
Authors
Garth E. Graham, Erin E. Marsh, Heather A. Lowers, Ryan D. Taylor
The Mount Weld rare earth element deposit, Western Australia: A carbonatite-derived laterite The Mount Weld rare earth element deposit, Western Australia: A carbonatite-derived laterite
Carbonatite-hosted rare earth element (REE) deposits are the primary source of the world’s light REEs and have the potential to be a source of heavy REEs. The Mount Weld REE deposit in Western Australia is hosted in a lateritic sequence that reflects supergene enrichment of the underlying carbonatite complex. Similar to other carbonatite-related ore deposits, ore from Mount Weld displays...
Authors
Philip Verplanck, Heather A. Lowers, Adam Boehlke, Jay Michael Thompson, Ganesh Bhat, Cameron Mark Mercer
Hyperspectral cathodoluminescence and quantitative EPMA mapping of angrite northwest Africa 15507 Hyperspectral cathodoluminescence and quantitative EPMA mapping of angrite northwest Africa 15507
Angrite meteorites represent alkali depleted planetary crust of basaltic composition, and have both plutonic and volcanic lithologies. NWA 15507 is a microgabbroic specimen (mean grainsize ~1.4 mm) composed predominantly of zoned Al-Ti-augite, Ca-bearing olivine and anorthite together with accessory kirschsteinite, rhönite, hercynite, low-Ni kamacite, merrillite, magnetite and troilite...
Authors
Heather A. Lowers, Jay Michael Thompson, Paul K. Carpenter, Zoe Wilbur, Anthony Irving
Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA
The Proterozoic tectonic evolution of the south-western USA remains incompletely understood due to limited constraints on the timing and conditions of the tectono-metamorphic phases and depositional age of metasedimentary successions. We integrated multi-scale compositional mapping, petrologic modeling, and in situ geochronology to constrain pressure-temperature-time paths from samples...
Authors
Ian William Hillenbrand, Michael L. Williams, Karl E. Karlstrom, Amy K. Gilmer, Heather A. Lowers, Michael J. Jercinovic, Kaitlyn Suarez, Amanda Souders
Characterizing lung particulates using quantitative microscopy in coal miners with severe pneumoconiosis Characterizing lung particulates using quantitative microscopy in coal miners with severe pneumoconiosis
Context.— Current approaches for characterizing retained lung dust using pathologists' qualitative assessment or scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) have limitations. Objective.— To explore polarized light microscopy coupled with image-processing software, termed quantitative microscopy–particulate matter (QM-PM), as a tool to characterize in situ...
Authors
Jeremy T. Hua, Carlyne D. Cool, Heather A. Lowers, Leonard H. T. Go, Lauren M. Zell-Baran, Emily A. Sarver, Kirsten S. Almberg, Kathy D. Pang, Susan M. Majka, Angela D. Franko, Naseema I. Vorajee, Robert A. Cohen, Cecil S. Rose