Heather A Lowers
Heather Lowers is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
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The distribution and composition of REE-bearing minerals in placers of the Atlantic and Gulf coastal plains, USA
Rare earth element (REE) resources are currently of great interest because of their importance as raw materials for high-technology manufacturing. The REE-phosphates monazite (light REE enriched) and xenotime (heavy REE enriched) resist weathering and can accumulate in placer deposits as part of the heavy mineral assemblage. The Atlantic and Gulf coastal plains of the southeastern United States ar
Authors
Carleton R. Bern, Anjana K. Shah, William Benzel, Heather A. Lowers
Ore mineralogy and textural zonation in the world-class epithermal Waihi Vein System, Hauraki Goldfield
The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The central veins (Amaranth, Trio, and Union) contain p
Authors
Jeffrey L. Mauk, Erin G Skinner, Sarah J Fyfe, Andrew H Menzies, Heather A. Lowers, Alan E. Koenig
Petrology and diagenetic history of the upper shale member of the Late Devonian-Early Mississippian Bakken Formation, Williston Basin, North Dakota
The organic-rich upper shale member of the upper Devonian–lower Mississippian Bakken Formation (Williston Basin, North Dakota, USA) has undergone significant diagenetic alteration, irrespective of catagenesis related to hydrocarbon generation. Alteration includes precipitation of numerous cements, replacement of both detrital and authigenic minerals, multiple episodes of fracturing, and compaction
Authors
Neil S. Fishman, Sven O. Egenhoff, Adam Boehlke, Heather A. Lowers
Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California
The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project near the modern San Francisco Bay shore in San Lorenzo, California. As a part of the Bayside Groundwater Project, East Bay Municipal Utility District proposed an aquifer stora
Authors
Michelle Sneed, Patricia v.P. Orlando, James W. Borchers, Rhett R. Everett, Michael Solt, Mary McGann, Heather Lowers, Shannon Mahan
Sedimentology of SPICE (Steptoean positive carbon isotope excursion): A high-resolution trace fossil and microfabric analysis of the middle to late Cambrian Alum Shale Formation, southern Sweden
The Cambrian Alum Shale Formation in the Andrarum-3 core from Scania, southern Sweden, consists of black siliciclastic mudstone with minor carbonate intercalations. Four facies comprise three siliciclastic mudstones and one fine-grained carbonate. The facies reflect deposition along a transect from deep ramp to basin on a Cambrian shelf. The three mudstone facies contain abundant clay clasts and l
Authors
Sven Egenhoff, Neil Fishman, Per Ahlberg, Jorg Maletz, Allison Jackson, Ketki Kolte, Heather A. Lowers, James Mackie, Warren Newby, Matthew Petrowsky
Characterisation of a natural quartz crystal as a reference material for microanalytical determination of Ti, Al, Li, Fe, Mn, Ga and Ge
A natural smoky quartz crystal from Shandong province, China, was characterised by laser ablation ICP-MS, electron probe microanalysis (EPMA) and solution ICP-MS to determine the concentration of twenty-four trace and ultra trace elements. Our main focus was on Ti quantification because of the increased use of this element for titanium-in-quartz (TitaniQ) thermobarometry. Pieces of a uniform growt
Authors
Andreas Audetat, Dieter Garbe-Schonberg, Andreas Kronz, Thomas Pettke, Brian G. Rusk, John J. Donovan, Heather Lowers
Evaluation of selected static methods used to estimate element mobility, acid-generating and acid-neutralizing potentials associated with geologically diverse mining wastes
A comparison study of selected static leaching and acid–base accounting (ABA) methods using a mineralogically diverse set of 12 modern-style, metal mine waste samples was undertaken to understand the relative performance of the various tests. To complement this study, in-depth mineralogical studies were conducted in order to elucidate the relationships between sample mineralogy, weathering feature
Authors
Philip L. Hageman, Robert R. Seal, Sharon F. Diehl, Nadine M. Piatak, Heather Lowers
The Lepanto Cu–Au deposit, Philippines: A fossil hyperacidic volcanic lake complex
Hyperacidic lakes and associated solfatara in active volcanoes are the expression of magmatic gas expansion from source to surface. Here we show for the first time, that the vein system that comprises the ~ 2 Ma high-sulfidation, Lepanto copper–gold deposit in the Mankayan district (Philippines) was associated with a contemporary hyperacidic volcanic lake complex—possibly the first such lake recog
Authors
Byron R. Berger, Richard W. Henley, Heather A. Lowers, Michael Pribil
Assessment of the geoavailability of trace elements from selected zinc minerals
This assessment focused on five zinc-bearing minerals. The minerals were subjected to a number of analyses including quantitative X-ray diffraction, optical microscopy, leaching tests, and bioaccessibility and toxicity studies. Like a previous comprehensive assessment of five copper-bearing minerals, the purpose of this assessment was to obtain structural and chemical information and to characteri
Authors
Rhonda L. Driscoll, Phillip L. Hageman, William Benzel, Sharon F. Diehl, Suzette Morman, LaDonna M. Choate, Heather Lowers
Mapping advanced argillic alteration at Cuprite, Nevada, using imaging spectroscopy
Mineral maps based on Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were used to study late Miocene advanced argillic alteration at Cuprite, Nevada. Distributions of Fe-bearing minerals, clays, micas, sulfates, and carbonates were mapped using the Tetracorder spectral-shape matching system. The Al content of white micas increases toward altered areas and near intrusive rocks. Alunit
Authors
Gregg A. Swayze, Roger N. Clark, Alexander F.H. Goetz, K. Eric Livo, George N. Breit, Fred A. Kruse, Stephen J. Sutley, Lawrence W. Snee, Heather A. Lowers, James L. Post, Roger E. Stoffregen, Roger P. Ashley
Epidote from the Zard Mountains, Kharan, Balochistan, Pakistan
The authors received two unusual crystals of epidote from Rock Currier, Jewel Tunnel Imports, in 2012. The mineral specimens were collected at Zard Mountain (Zard Koh), in the central part of the Ruskoh Mountains (Rusk Koh), west of Kharan, Balochistan, Pakistan (written communication, Rock Currier, 2013). The epidote locality was most likely discovered in 2010. These epidote crystals were unusual
Authors
Michael E. Brownfield, Heather Lowers, William K. Betterton
Linking geology and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria
Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more.
Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional to
Authors
Geoffrey S. Plumlee, James T. Durant, Suzette A. Morman, Antonio Neri, Ruth E. Wolf, Carrie A. Dooyema, Philip L. Hageman, Heather Lowers, Gregory L. Fernette, Gregory P. Meeker, William Benzel, Rhonda L. Driscoll, Cyrus J. Berry, James G. Crock, Harland L. Goldstein, Monique Adams, Casey L. Bartrem, Simba Tirima, Behbod Behrooz, Ian von Lindern, Mary Jean Brown
Science and Products
Filter Total Items: 25
No Result Found
Filter Total Items: 99
The distribution and composition of REE-bearing minerals in placers of the Atlantic and Gulf coastal plains, USA
Rare earth element (REE) resources are currently of great interest because of their importance as raw materials for high-technology manufacturing. The REE-phosphates monazite (light REE enriched) and xenotime (heavy REE enriched) resist weathering and can accumulate in placer deposits as part of the heavy mineral assemblage. The Atlantic and Gulf coastal plains of the southeastern United States ar
Authors
Carleton R. Bern, Anjana K. Shah, William Benzel, Heather A. Lowers
Ore mineralogy and textural zonation in the world-class epithermal Waihi Vein System, Hauraki Goldfield
The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The central veins (Amaranth, Trio, and Union) contain p
Authors
Jeffrey L. Mauk, Erin G Skinner, Sarah J Fyfe, Andrew H Menzies, Heather A. Lowers, Alan E. Koenig
Petrology and diagenetic history of the upper shale member of the Late Devonian-Early Mississippian Bakken Formation, Williston Basin, North Dakota
The organic-rich upper shale member of the upper Devonian–lower Mississippian Bakken Formation (Williston Basin, North Dakota, USA) has undergone significant diagenetic alteration, irrespective of catagenesis related to hydrocarbon generation. Alteration includes precipitation of numerous cements, replacement of both detrital and authigenic minerals, multiple episodes of fracturing, and compaction
Authors
Neil S. Fishman, Sven O. Egenhoff, Adam Boehlke, Heather A. Lowers
Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California
The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project near the modern San Francisco Bay shore in San Lorenzo, California. As a part of the Bayside Groundwater Project, East Bay Municipal Utility District proposed an aquifer stora
Authors
Michelle Sneed, Patricia v.P. Orlando, James W. Borchers, Rhett R. Everett, Michael Solt, Mary McGann, Heather Lowers, Shannon Mahan
Sedimentology of SPICE (Steptoean positive carbon isotope excursion): A high-resolution trace fossil and microfabric analysis of the middle to late Cambrian Alum Shale Formation, southern Sweden
The Cambrian Alum Shale Formation in the Andrarum-3 core from Scania, southern Sweden, consists of black siliciclastic mudstone with minor carbonate intercalations. Four facies comprise three siliciclastic mudstones and one fine-grained carbonate. The facies reflect deposition along a transect from deep ramp to basin on a Cambrian shelf. The three mudstone facies contain abundant clay clasts and l
Authors
Sven Egenhoff, Neil Fishman, Per Ahlberg, Jorg Maletz, Allison Jackson, Ketki Kolte, Heather A. Lowers, James Mackie, Warren Newby, Matthew Petrowsky
Characterisation of a natural quartz crystal as a reference material for microanalytical determination of Ti, Al, Li, Fe, Mn, Ga and Ge
A natural smoky quartz crystal from Shandong province, China, was characterised by laser ablation ICP-MS, electron probe microanalysis (EPMA) and solution ICP-MS to determine the concentration of twenty-four trace and ultra trace elements. Our main focus was on Ti quantification because of the increased use of this element for titanium-in-quartz (TitaniQ) thermobarometry. Pieces of a uniform growt
Authors
Andreas Audetat, Dieter Garbe-Schonberg, Andreas Kronz, Thomas Pettke, Brian G. Rusk, John J. Donovan, Heather Lowers
Evaluation of selected static methods used to estimate element mobility, acid-generating and acid-neutralizing potentials associated with geologically diverse mining wastes
A comparison study of selected static leaching and acid–base accounting (ABA) methods using a mineralogically diverse set of 12 modern-style, metal mine waste samples was undertaken to understand the relative performance of the various tests. To complement this study, in-depth mineralogical studies were conducted in order to elucidate the relationships between sample mineralogy, weathering feature
Authors
Philip L. Hageman, Robert R. Seal, Sharon F. Diehl, Nadine M. Piatak, Heather Lowers
The Lepanto Cu–Au deposit, Philippines: A fossil hyperacidic volcanic lake complex
Hyperacidic lakes and associated solfatara in active volcanoes are the expression of magmatic gas expansion from source to surface. Here we show for the first time, that the vein system that comprises the ~ 2 Ma high-sulfidation, Lepanto copper–gold deposit in the Mankayan district (Philippines) was associated with a contemporary hyperacidic volcanic lake complex—possibly the first such lake recog
Authors
Byron R. Berger, Richard W. Henley, Heather A. Lowers, Michael Pribil
Assessment of the geoavailability of trace elements from selected zinc minerals
This assessment focused on five zinc-bearing minerals. The minerals were subjected to a number of analyses including quantitative X-ray diffraction, optical microscopy, leaching tests, and bioaccessibility and toxicity studies. Like a previous comprehensive assessment of five copper-bearing minerals, the purpose of this assessment was to obtain structural and chemical information and to characteri
Authors
Rhonda L. Driscoll, Phillip L. Hageman, William Benzel, Sharon F. Diehl, Suzette Morman, LaDonna M. Choate, Heather Lowers
Mapping advanced argillic alteration at Cuprite, Nevada, using imaging spectroscopy
Mineral maps based on Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were used to study late Miocene advanced argillic alteration at Cuprite, Nevada. Distributions of Fe-bearing minerals, clays, micas, sulfates, and carbonates were mapped using the Tetracorder spectral-shape matching system. The Al content of white micas increases toward altered areas and near intrusive rocks. Alunit
Authors
Gregg A. Swayze, Roger N. Clark, Alexander F.H. Goetz, K. Eric Livo, George N. Breit, Fred A. Kruse, Stephen J. Sutley, Lawrence W. Snee, Heather A. Lowers, James L. Post, Roger E. Stoffregen, Roger P. Ashley
Epidote from the Zard Mountains, Kharan, Balochistan, Pakistan
The authors received two unusual crystals of epidote from Rock Currier, Jewel Tunnel Imports, in 2012. The mineral specimens were collected at Zard Mountain (Zard Koh), in the central part of the Ruskoh Mountains (Rusk Koh), west of Kharan, Balochistan, Pakistan (written communication, Rock Currier, 2013). The epidote locality was most likely discovered in 2010. These epidote crystals were unusual
Authors
Michael E. Brownfield, Heather Lowers, William K. Betterton
Linking geology and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria
Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more.
Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional to
Authors
Geoffrey S. Plumlee, James T. Durant, Suzette A. Morman, Antonio Neri, Ruth E. Wolf, Carrie A. Dooyema, Philip L. Hageman, Heather Lowers, Gregory L. Fernette, Gregory P. Meeker, William Benzel, Rhonda L. Driscoll, Cyrus J. Berry, James G. Crock, Harland L. Goldstein, Monique Adams, Casey L. Bartrem, Simba Tirima, Behbod Behrooz, Ian von Lindern, Mary Jean Brown