David T Adams (Former Employee)
Science and Products
Denver Microbeam Laboratory: Mineral Resources Research Support
The USGS Denver Microbeam Laboratory provides chemical analysis and characterization of rocks, minerals, and environmental samples in support of a wide variety of USGS projects related to mineral resources, including research projects funded by the USGS Mineral Resources Program. The research applications for these projects range from mineral resource research and assessments, to geologic mapping...
Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district
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
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
Electron microprobe data for monazite and xenotime used in consideration of gold deposit formation models (ver. 2.0, May 2023)
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 ar
Absence of magnetite microlites, geochemistry of magnetite veins and replacements in IOA deposits, SE Missouri, USA: Relations to intermediate intrusions
The paragenesis, textures, and chemical compositions of magnetite in two mafic to intermediate intrusions and four IOA deposits in SE Missouri were studied to discriminate between igneous and hydrothermal sources. In this study, we found that replacement magnetite with mineral inclusion-rich cores yields erroneously high Ti, Al, Si, Mg, and Mn contents as determined by EMP and LA-ICP-MS due to ru
Authors
Corey J. Meighan, Albert H. Hofstra, David Adams, Erin E. Marsh, Heather A. Lowers, Alan Koenig
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, the prima
Authors
Cliff D. Taylor, Heather A. Lowers, David Adams, R. James Robinson
Pre-eruptive conditions of the Hideaway Park topaz rhyolite: Insights into metal source and evolution of magma parental to the Henderson porphyry molybdenum deposit, Colorado
The Hideaway Park tuff is the only preserved extrusive volcanic unit related to the Red Mountain intrusive complex, which produced the world-class Henderson porphyry Mo deposit. Located within the Colorado Mineral Belt, USA, Henderson is the second largest Climax-type Mo deposit in the world, and is therefore an excellent location to investigate magmatic processes leading to Climax-type Mo mineral
Authors
Celestine N. Mercer, Albert H. Hofstra, Todor I. Todorov, Julie Roberge, Alain Burgisser, David T. Adams, Michael A. Cosca
Assessment of the geoavailability of trace elements from minerals in mine wastes: analytical techniques and assessment of selected copper minerals
In this study, four randomly selected copper-bearing minerals were examined—azurite, malachite, bornite, and chalcopyrite. The objectives were to examine and enumerate the crystalline and chemical properties of each of the minerals, to determine which, if any, of the Cu-bearing minerals might adversely affect systems biota, and to provide a multi-procedure reference. Laboratory work included use o
Authors
Rhonda Driscoll, Phillip L. Hageman, William Benzel, Sharon F. Diehl, David T. Adams, Suzette Morman, LaDonna M. Choate
The dispersion of fibrous amphiboles by glacial processes in the area surrounding Libby, Montana, USA
Mining operations began at a world-class vermiculite deposit at Vermiculite Mountain near Libby, Montana, circa 1920 and ended in 1990. Fibrous and asbestiform amphiboles intergrown with vermiculite ore are suspected to be a causative factor in an abnormally high number of cases of respiratory diseases in former mine and mill workers, and in residents of Libby. The question addressed in this repor
Authors
William H. Langer, Bradley S. Van Gosen, Gregory P. Meeker, David T. Adams, Todd M. Hoefen
Origin of minor and trace element compositional diversity in anorthitic feldspar phenocrysts and melt inclusions from the Juan de Fuca Ridge
Melt inclusions trapped in phenocryst phases are important primarily due to their potential of preserving a significant proportion of the diversity of magma composition prior to modification of the parent magma array during transport through the crust. The goal of this investigation was to evaluate the impact of formational and post-entrapment processes on the composition of melt inclusions hosted
Authors
David T. Adams, Roger L. Nielsen, Adam J. R. Kent, Frank J. Tepley
Chemical and morphological comparison of erionite from Oregon, North Dakota, and Turkey
Erionite, a fibrous zeolite, occurs in pediment gravel deposits near Killdeer Mountain, North Dakota. Material from these pediment deposits has been excavated for use as roadbed throughout Dunn County, North Dakota. Erionite also occurs in the Cappadocian region of Turkey, where a link between malignant mesothelioma and inhalation of this mineral has been established. The U.S. Environmental Protec
Authors
Heather Lowers, David T. Adams, Gregory P. Meeker, Constance J. Nutt
Petrology and hydrothermal alteration of Jurassic intrusive rocks associated with gold deposits in the Bald Mountain mining district, White Pine County, Nevada
No abstract available.
Authors
Edward A. du Bray, J. Thomas Nash, Gregory P. Meeker, David Adams, William A. Wright
Examination of Libby, Montana, Fill Material for Background Levels of Amphibole from the Rainy Creek Complex Using Scanning Electron Microscopy and X-Ray Microanalysis
Natural background levels of Libby-type amphibole in the sediment of the Libby valley in Montana have not, up to this point, been determined. The purpose of this report is to provide the preliminary findings of a study designed by both the U.S. Geological Survey and the U.S. Environmental Protection Agency and performed by the U.S. Geological Survey. The study worked to constrain the natural backg
Authors
David T. Adams, William H. Langer, Todd M. Hoefen, Bradley S. Van Gosen, Gregory P. Meeker
Europium-rich dark monazite - a potential new ore mineral for Alaska, USA?
No abstract available.
Authors
Richard B. Tripp, William Benzel, David T. Adams, Heather A. Lowers, Gregory K. Lee, Elizabeth A. Bailey
Science and Products
Denver Microbeam Laboratory: Mineral Resources Research Support
The USGS Denver Microbeam Laboratory provides chemical analysis and characterization of rocks, minerals, and environmental samples in support of a wide variety of USGS projects related to mineral resources, including research projects funded by the USGS Mineral Resources Program. The research applications for these projects range from mineral resource research and assessments, to geologic mapping...
Trace element chemistry of sulfides and quartz, in situ sulfur isotope values of sulfides, cathodoluminescence of quartz, fluid inclusion microthermometry and raman, and radiogenic isotope and whole rock geochemistry from the Stibnite-Yellow Pine district
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
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
Electron microprobe data for monazite and xenotime used in consideration of gold deposit formation models (ver. 2.0, May 2023)
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 ar
Absence of magnetite microlites, geochemistry of magnetite veins and replacements in IOA deposits, SE Missouri, USA: Relations to intermediate intrusions
The paragenesis, textures, and chemical compositions of magnetite in two mafic to intermediate intrusions and four IOA deposits in SE Missouri were studied to discriminate between igneous and hydrothermal sources. In this study, we found that replacement magnetite with mineral inclusion-rich cores yields erroneously high Ti, Al, Si, Mg, and Mn contents as determined by EMP and LA-ICP-MS due to ru
Authors
Corey J. Meighan, Albert H. Hofstra, David Adams, Erin E. Marsh, Heather A. Lowers, Alan Koenig
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, the prima
Authors
Cliff D. Taylor, Heather A. Lowers, David Adams, R. James Robinson
Pre-eruptive conditions of the Hideaway Park topaz rhyolite: Insights into metal source and evolution of magma parental to the Henderson porphyry molybdenum deposit, Colorado
The Hideaway Park tuff is the only preserved extrusive volcanic unit related to the Red Mountain intrusive complex, which produced the world-class Henderson porphyry Mo deposit. Located within the Colorado Mineral Belt, USA, Henderson is the second largest Climax-type Mo deposit in the world, and is therefore an excellent location to investigate magmatic processes leading to Climax-type Mo mineral
Authors
Celestine N. Mercer, Albert H. Hofstra, Todor I. Todorov, Julie Roberge, Alain Burgisser, David T. Adams, Michael A. Cosca
Assessment of the geoavailability of trace elements from minerals in mine wastes: analytical techniques and assessment of selected copper minerals
In this study, four randomly selected copper-bearing minerals were examined—azurite, malachite, bornite, and chalcopyrite. The objectives were to examine and enumerate the crystalline and chemical properties of each of the minerals, to determine which, if any, of the Cu-bearing minerals might adversely affect systems biota, and to provide a multi-procedure reference. Laboratory work included use o
Authors
Rhonda Driscoll, Phillip L. Hageman, William Benzel, Sharon F. Diehl, David T. Adams, Suzette Morman, LaDonna M. Choate
The dispersion of fibrous amphiboles by glacial processes in the area surrounding Libby, Montana, USA
Mining operations began at a world-class vermiculite deposit at Vermiculite Mountain near Libby, Montana, circa 1920 and ended in 1990. Fibrous and asbestiform amphiboles intergrown with vermiculite ore are suspected to be a causative factor in an abnormally high number of cases of respiratory diseases in former mine and mill workers, and in residents of Libby. The question addressed in this repor
Authors
William H. Langer, Bradley S. Van Gosen, Gregory P. Meeker, David T. Adams, Todd M. Hoefen
Origin of minor and trace element compositional diversity in anorthitic feldspar phenocrysts and melt inclusions from the Juan de Fuca Ridge
Melt inclusions trapped in phenocryst phases are important primarily due to their potential of preserving a significant proportion of the diversity of magma composition prior to modification of the parent magma array during transport through the crust. The goal of this investigation was to evaluate the impact of formational and post-entrapment processes on the composition of melt inclusions hosted
Authors
David T. Adams, Roger L. Nielsen, Adam J. R. Kent, Frank J. Tepley
Chemical and morphological comparison of erionite from Oregon, North Dakota, and Turkey
Erionite, a fibrous zeolite, occurs in pediment gravel deposits near Killdeer Mountain, North Dakota. Material from these pediment deposits has been excavated for use as roadbed throughout Dunn County, North Dakota. Erionite also occurs in the Cappadocian region of Turkey, where a link between malignant mesothelioma and inhalation of this mineral has been established. The U.S. Environmental Protec
Authors
Heather Lowers, David T. Adams, Gregory P. Meeker, Constance J. Nutt
Petrology and hydrothermal alteration of Jurassic intrusive rocks associated with gold deposits in the Bald Mountain mining district, White Pine County, Nevada
No abstract available.
Authors
Edward A. du Bray, J. Thomas Nash, Gregory P. Meeker, David Adams, William A. Wright
Examination of Libby, Montana, Fill Material for Background Levels of Amphibole from the Rainy Creek Complex Using Scanning Electron Microscopy and X-Ray Microanalysis
Natural background levels of Libby-type amphibole in the sediment of the Libby valley in Montana have not, up to this point, been determined. The purpose of this report is to provide the preliminary findings of a study designed by both the U.S. Geological Survey and the U.S. Environmental Protection Agency and performed by the U.S. Geological Survey. The study worked to constrain the natural backg
Authors
David T. Adams, William H. Langer, Todd M. Hoefen, Bradley S. Van Gosen, Gregory P. Meeker
Europium-rich dark monazite - a potential new ore mineral for Alaska, USA?
No abstract available.
Authors
Richard B. Tripp, William Benzel, David T. Adams, Heather A. Lowers, Gregory K. Lee, Elizabeth A. Bailey