Heather A Lowers
Heather Lowers is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 31
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Filter Total Items: 106
Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes
The paragenesis, textures, and chemical compositions of secondary hematite in regional potassic altered rhyolites, four IOA deposits, the sedimentary iron deposit at Pilot Knob and the Boss IOCG deposit in SE Missouri were determined and compared to primary magnetite from the IOA and IOCG deposits. Magnetite is composed of elements characteristics of mafic to intermediate intrusions...
Authors
Corey J. Meighan, Albert H. Hofstra, Erin E. Marsh, Heather A. Lowers, Alan Koenig
Method to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy Method to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy
Humans accumulate large numbers of inorganic particles in their lungs over a lifetime. Whether this causes or contributes to debilitating disease over a normal lifespan depends on the type and concentration of the particles. We developed and tested a protocol for in situ characterization of the types and distribution of inorganic particles in biopsied lung tissue from three human groups...
Authors
Heather A. Lowers, George N. Breit, Matthew Strand, Renee M. Pillers, Gregory P. Meeker, Todor I. Todorov, Geoffrey S. Plumlee, Ruth E. Wolf, Maura Robinson, Jane Parr, Robert J. Miller, Steve Groshong, Francis Green, Cecile Rose
Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Commercially produced vermiculite insulation from Libby, Montana, contains trace levels of asbestiform amphibole, which is known to cause asbestos-related diseases. When vermiculite insulation is found in a building, evaluation for its potential asbestos content traditionally involves collecting a sample from an attic or wall and submitting it for time-consuming analyses at an off-site...
Authors
Gregg A. Swayze, Heather A. Lowers, William Benzel, Roger N. Clark, Rhonda L. Driscoll, Zac S. Perlman, Todd M. Hoefen, M. Darby Dyar
Geochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA Geochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA
The Bokan Mountain igneous complex (BMIC) is a typical example of a peralkaline intrusive system that has evolved to the point of developing late stage HFSE- and REE-rich silicic pegmatites and dikes. The Dotson Zone comprises a series of felsic dikes that extend from the southeast margin of the composite pluton and may represent an important resource of critical HREEs. Petrographically...
Authors
Cliff D. Taylor, Heather A. Lowers, David Adams, R. James Robinson
Organic petrology and micro-spectroscopy of Tasmanites microfossils: Applications to kerogen transformations in the early oil window Organic petrology and micro-spectroscopy of Tasmanites microfossils: Applications to kerogen transformations in the early oil window
The transformation of kerogen to hydrocarbons in the early stages of oil generation is critical for understanding the resource potential of liquid-rich shale plays. Organic petrology commonly is used for visual evaluation of type, quality, and thermal maturity of organic matter, but the relationship of visual petrographic changes to chemical transformations is not well characterized. To...
Authors
Paul C. Hackley, Clifford C. Walters, S.R. Kelemen, Maria Mastalerz, Heather A. Lowers
USGS Spectral Library Version 7 USGS Spectral Library Version 7
We have assembled a library of spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns [μm]). Laboratory samples of specific minerals, plants, chemical compounds, and manmade materials were measured. In many cases, samples were purified, so that unique spectral features of a...
Authors
Raymond F. Kokaly, Roger N. Clark, Gregg A. Swayze, K. Eric Livo, Todd M. Hoefen, Neil C. Pearson, Richard A. Wise, William Benzel, Heather A. Lowers, Rhonda L. Driscoll, Anna J. Klein
Science and Products
Filter Total Items: 31
No Result Found
Filter Total Items: 106
Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes
The paragenesis, textures, and chemical compositions of secondary hematite in regional potassic altered rhyolites, four IOA deposits, the sedimentary iron deposit at Pilot Knob and the Boss IOCG deposit in SE Missouri were determined and compared to primary magnetite from the IOA and IOCG deposits. Magnetite is composed of elements characteristics of mafic to intermediate intrusions...
Authors
Corey J. Meighan, Albert H. Hofstra, Erin E. Marsh, Heather A. Lowers, Alan Koenig
Method to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy Method to characterize inorganic particulates in lung tissue biopsies using field emission scanning electron microscopy
Humans accumulate large numbers of inorganic particles in their lungs over a lifetime. Whether this causes or contributes to debilitating disease over a normal lifespan depends on the type and concentration of the particles. We developed and tested a protocol for in situ characterization of the types and distribution of inorganic particles in biopsied lung tissue from three human groups...
Authors
Heather A. Lowers, George N. Breit, Matthew Strand, Renee M. Pillers, Gregory P. Meeker, Todor I. Todorov, Geoffrey S. Plumlee, Ruth E. Wolf, Maura Robinson, Jane Parr, Robert J. Miller, Steve Groshong, Francis Green, Cecile Rose
Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Commercially produced vermiculite insulation from Libby, Montana, contains trace levels of asbestiform amphibole, which is known to cause asbestos-related diseases. When vermiculite insulation is found in a building, evaluation for its potential asbestos content traditionally involves collecting a sample from an attic or wall and submitting it for time-consuming analyses at an off-site...
Authors
Gregg A. Swayze, Heather A. Lowers, William Benzel, Roger N. Clark, Rhonda L. Driscoll, Zac S. Perlman, Todd M. Hoefen, M. Darby Dyar
Geochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA Geochemistry and mineralogy of the Dotson Zone HREE deposit in the Bokan Mountain peralkaline igneous complex, southeastern Alaska, USA
The Bokan Mountain igneous complex (BMIC) is a typical example of a peralkaline intrusive system that has evolved to the point of developing late stage HFSE- and REE-rich silicic pegmatites and dikes. The Dotson Zone comprises a series of felsic dikes that extend from the southeast margin of the composite pluton and may represent an important resource of critical HREEs. Petrographically...
Authors
Cliff D. Taylor, Heather A. Lowers, David Adams, R. James Robinson
Organic petrology and micro-spectroscopy of Tasmanites microfossils: Applications to kerogen transformations in the early oil window Organic petrology and micro-spectroscopy of Tasmanites microfossils: Applications to kerogen transformations in the early oil window
The transformation of kerogen to hydrocarbons in the early stages of oil generation is critical for understanding the resource potential of liquid-rich shale plays. Organic petrology commonly is used for visual evaluation of type, quality, and thermal maturity of organic matter, but the relationship of visual petrographic changes to chemical transformations is not well characterized. To...
Authors
Paul C. Hackley, Clifford C. Walters, S.R. Kelemen, Maria Mastalerz, Heather A. Lowers
USGS Spectral Library Version 7 USGS Spectral Library Version 7
We have assembled a library of spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns [μm]). Laboratory samples of specific minerals, plants, chemical compounds, and manmade materials were measured. In many cases, samples were purified, so that unique spectral features of a...
Authors
Raymond F. Kokaly, Roger N. Clark, Gregg A. Swayze, K. Eric Livo, Todd M. Hoefen, Neil C. Pearson, Richard A. Wise, William Benzel, Heather A. Lowers, Rhonda L. Driscoll, Anna J. Klein