Publications
Products (journal articles, reports, fact sheets) authored by current and past scientists are listed below. Please check the USGS Pubs Warehouse for other USGS publications.
Filter Total Items: 1944
40Ar/39Ar geochronology and petrogenesis of the Table Mountain Shoshonite, Golden, Colorado, U.S.A. 40Ar/39Ar geochronology and petrogenesis of the Table Mountain Shoshonite, Golden, Colorado, U.S.A.
The Upper Cretaceous and Lower Paleogene Table Mountain Shoshonite lava flows and their proposed source, the Ralston Buttes intrusions, provide insight into the volcanic history of the Colorado Front Range. This study affirms the long-held hypothesis linking the extrusive Table Mountain lava flows and their intrusive equivalents at Ralston Buttes through major- and trace- element...
Authors
Alexie E. G. Millikin, Leah E. Morgan, Jeffery Noblett
Quartz-pebble-conglomerate gold deposits Quartz-pebble-conglomerate gold deposits
Quartz-pebble-conglomerate gold deposits represent the largest repository of gold on Earth, largely due to the deposits of the Witwatersrand Basin, which account for nearly 40 percent of the total gold produced throughout Earth’s history. This deposit type has had a controversial history in regards to genetic models. However, most researchers conclude that they are paleoplacer deposits...
Authors
Ryan D. Taylor, Eric D. Anderson
Three-dimensional geophysical mapping of shallow water saturated altered rocks at Mount Baker, Washington: Implications for slope stability Three-dimensional geophysical mapping of shallow water saturated altered rocks at Mount Baker, Washington: Implications for slope stability
Water-saturated hydrothermal alteration reduces the strength of volcanic edifices, increasing the potential for catastrophic sector collapses that can lead to far traveled and destructive debris flows. Intense hydrothermal alteration significantly lowers the resistivity and magnetization of volcanic rock and therefore hydrothermally altered rocks can be identified with helicopter...
Authors
Carol A. Finn, Maria Deszcz-Pan, Jessica L. Ball, Benjamin J. Bloss, Burke J. Minsley
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2016 annual report U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2016 annual report
This is the ninth annual report highlighting U.S. Geological Survey (USGS) science and decision-support activities conducted for the Wyoming Landscape Conservation Initiative (WLCI). The activities address specific management needs identified by WLCI partner agencies. In fiscal year (FY) 2016, there were 26 active USGS WLCI science-based projects. Of these 26 projects, one project was...
Authors
Zachary H. Bowen, Ellen Aikens, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Anna D. Chalfoun, Geneva W. Chong, Cheryl A. Eddy-Miller, Steven L. Garman, Steve Germaine, Collin G. Homer, Aaron N. Johnston, Matthew J. Kauffman, Daniel J. Manier, Cynthia P. Melcher, Kirk A. Miller, Annika W. Walters, Jerrod D. Wheeler, Daniel J. Wieferich, Anna B. Wilson, Teal B. Wyckoff, Linda Zeigenfuss
By
Ecosystems Mission Area, Water Resources Mission Area, Science Synthesis, Analysis, and Research Program, Land Management Research Program, Science Analytics and Synthesis (SAS), Species Management Research Program, Earth Resources Observation and Science (EROS) Center, Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center, Northern Rocky Mountain Science Center, Wyoming-Montana Water Science Center
Comment on "Next-Generation Ice Core Technology Reveals True Minimum Natural Levels of lead (Pb) in the atmosphere: Insights from the Black Death" by More et al. Comment on "Next-Generation Ice Core Technology Reveals True Minimum Natural Levels of lead (Pb) in the atmosphere: Insights from the Black Death" by More et al.
Results and interpretation of the subject article are surprising and conflict with expectations about atmospheric deposition of lead (Pb)Before interpretation of subject article is accepted a body of information about natural deposition of lead (Pb) must be consideredThis body of information includes knowledge of volcano emissions, chemistry of natural dusts, and isotopes of lead (Pb)
Authors
Todd K. Hinkley
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
Compilation of new and previously published geochemical and modal data for Mesoproterozoic igneous rocks of the St. Francois Mountains, southeast Missouri Compilation of new and previously published geochemical and modal data for Mesoproterozoic igneous rocks of the St. Francois Mountains, southeast Missouri
The purpose of this report is to present recently acquired as well as previously published geochemical and modal petrographic data for igneous rocks in the St. Francois Mountains, southeast Missouri, as part of an ongoing effort to understand the regional geology and ore deposits of the Mesoproterozoic basement rocks of southeast Missouri, USA. The report includes geochemical data that...
Authors
Edward A. du Bray, Warren C. Day, Corey J. Meighan
Titanium mineral resources in heavy-mineral sands in the Atlantic coastal plain of the southeastern United States Titanium mineral resources in heavy-mineral sands in the Atlantic coastal plain of the southeastern United States
This study examined titanium distribution in the Atlantic Coastal Plain of the southeastern United States; the titanium is found in heavy-mineral sands that include the minerals ilmenite (Fe2+TiO3), rutile (TiO2), or leucoxene (an alteration product of ilmenite). Deposits of heavy-mineral sands in ancient and modern coastal plains are a significant feedstock source for the titanium...
Authors
Bradley S. Van Gosen, Karl J. Ellefsen
Climate stability in Central Anatolia during the Messinian Salinity Crisis Climate stability in Central Anatolia during the Messinian Salinity Crisis
Deposition of large amounts of evaporites and erosion of deep canyons within the Mediterranean Basin as a result of reduced basin connectivity with the Atlantic Ocean and the epicontinental Paratethys Sea characterized the Messinian Salinity Crisis (MSC, 5.97–5.33 Ma). The influence of the MSC on Mediterranean environmental conditions within the basin itself has been intensely studied...
Authors
Maud J.M. Meijers, Ahmet A Peynircioglu, Michael A. Cosca, Gilles Y. Brocard, Donna L. Whitney, Cor G. Langereis, Andreas Mulch
Thermochronometry across the Austroalpine-Pennine boundary, Central Alps, Switzerland: Orogen-perpendicular normal fault slip on a major ‘overthrust’ and its implications for orogenesis Thermochronometry across the Austroalpine-Pennine boundary, Central Alps, Switzerland: Orogen-perpendicular normal fault slip on a major ‘overthrust’ and its implications for orogenesis
Fifty‐one new and 309 published thermochronometric ages (nine systems with closure temperatures ranging from ~450 to 70°C) from the Graubünden region of the Central Alps demonstrate that a pronounced thermal mismatch between the Austroalpine allochthon (Alpine “orogenic lid”) and the Pennine zone persisted until at least 29 Ma and, allowably, until circa 18 Ma. The observed mismatch...
Authors
Jason B. Price, Brian P. Wernicke, Michael A. Cosca, Kenneth A. Farley
In situ LA-ICPMS U–Pb dating of cassiterite without a known-age matrix-matched reference material: Examples from worldwide tin deposits spanning the Proterozoic to the Tertiary In situ LA-ICPMS U–Pb dating of cassiterite without a known-age matrix-matched reference material: Examples from worldwide tin deposits spanning the Proterozoic to the Tertiary
Cassiterite (SnO2), a main ore mineral in tin deposits, is suitable for U–Pb isotopic dating because of its relatively high U/Pb ratios and typically low common Pb. We report a LA-ICPMS analytical procedure for U–Pb dating of this mineral with no need for an independently dated matrix-matched cassiterite standard. LA-ICPMS U-Th-Pb data were acquired while using NIST 612 glass as a...
Authors
Leonid A. Neymark, Christopher S. Holm-Denoma, Richard J. Moscati
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