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: 1826
A process for reducing rocks and concentrating heavy minerals
To obtain minerals suitable for age-dating and other analyses, it is necessary to first reduce the mineral-bearing rock to a fine, sand-like consistency. Reducing whole rock requires crushing, grinding, and sieving. Ideally, the reduced material should range in size from 80- to 270-mesh (an opening between wires in a sieve). The openings in an 80-mesh sieve are equal to 0.007 inches, 0.177 millime
Authors
Thomas R. Strong, Rhonda L. Driscoll
Improving the ecological relevance of toxicity tests on scleractinian corals: Influence of season, life stage, and seawater temperature
Metal pollutants in marine systems are broadly acknowledged as deleterious: however, very little data exist for tropical scleractinian corals. We address this gap by investigating how life-history stage, season and thermal stress influence the toxicity of copper (Cu) and lead (Pb) in the coral Pocillopora damicornis. Our results show that under ambient temperature, adults and larvae appear to tole
Authors
Laetitia Hedouin, Ruth E. Wolf, Jeff Phillips, Ruth D. Gates
Critical elements in sediment-hosted deposits (clastic-dominated Zn-Pb-Ag, Mississippi Valley-type Zn-Pb, sedimentary rock-hosted Stratiform Cu, and carbonate-hosted Polymetallic Deposits): A review: Chapter 12
Some sediment-hosted base metal deposits, specifically the clastic-dominated (CD) Zn-Pb deposits, carbonate-hosted Mississippi Valley-type (MVT) deposits, sedimentary-rock hosted stratiform copper deposits, and carbonate-hosted polymetallic (“Kipushi type”) deposits, are or have been important sources of critical elements including Co, Ga, Ge, and Re. The generally poor data concerning trace elem
Authors
Erin E. Marsh, Murray W. Hitzman, David L. Leach
Paleozoic magmatism and porphyry Cu-mineralization in an evolving tectonic setting in the North Qilian Orogenic Belt, NW China
The NWW-striking North Qilian Orogenic Belt records the Paleozoic accretion–collision processes in NW China, and hosts Paleozoic Cu–Pb–Zn mineralization that was temporally and spatially related to the closure of the Paleo Qilian-Qinling Ocean. The Wangdian Cu deposit is located in the eastern part of the North Qilian Orogenic Belt, NW China. Copper mineralization is spatially associated with an a
Authors
Kun-Feng Qiu, Jun Deng, Ryan D. Taylor, Kai-Rui Song, Yao-Hui Song, Quan-Zhong Li, Richard J. Goldfarb
Isotope hydrology of the Chalk River Laboratories site, Ontario, Canada
This paper presents results of hydrochemical and isotopic analyses of groundwater (fracture water) and porewater, and physical property and water content measurements of bedrock core at the Chalk River Laboratories (CRL) site in Ontario. Density and water contents were determined and water-loss porosity values were calculated for core samples. Average and standard deviations of density and water-l
Authors
Zell E. Peterman, Leonid A. Neymark, K.J. King-Sharp, Mel Gascoyne
Thorium as a nuclear fuel
No abstract available.
Authors
Bradley S. Van Gosen, Harikrishnan Tulsidas
Critical elements in alkaline igneous rock-related epithermal gold deposits
No abstract available.
Authors
Karen D. Kelley, Paul G. Spry
Placer-type rare earth element deposits
No abstract available.
Authors
Debashish Sengupta, Bradley S. Van Gosen
Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables
Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the dynamic flux
Authors
Chris S. Eckley, Michael T. Tate, Che-Jen Lin, Mae S. Gustin, Stephen Dent, Collin A. Eagles-Smith, Michelle A. Lutz, Kimberly Wickland, Bronwen Wang, John E. Gray, Grant Edwards, David P. Krabbenhoft, David B. Smith
Groundwater ages from the freshwater zone of the Edwards aquifer, Uvalde County, Texas—Insights into groundwater flow and recharge
Tritium–helium-3 groundwater ages of the Edwards aquifer in south-central Texas were determined as part of a long-term study of groundwater flow and recharge in the Edwards and Trinity aquifers. These ages help to define groundwater residence times and to provide constraints for calibration of groundwater flow models. A suite of 17 samples from public and private supply wells within Uvalde County
Authors
Andrew G. Hunt, Gary P. Landis, Jason R. Faith
Developing integrated methods to address complex resource and environmental issues
IntroductionThis circular provides an overview of selected activities that were conducted within the U.S. Geological Survey (USGS) Integrated Methods Development Project, an interdisciplinary project designed to develop new tools and conduct innovative research requiring integration of geologic, geophysical, geochemical, and remote-sensing expertise. The project was supported by the USGS Mineral R
The link between volcanism and plutonism in epizonal magma systems; high-precision U–Pb zircon geochronology from the Organ Mountains caldera and batholith, New Mexico
The Organ Mountains caldera and batholith expose the volcanic and epizonal plutonic record of an Eocene caldera complex. The caldera and batholith are well exposed, and extensive previous mapping and geochemical analyses have suggested a clear link between the volcanic and plutonic sections, making this an ideal location to study magmatic processes associated with caldera volcanism. Here we presen
Authors
Matthew Rioux, Lang Farmer, Samuel Bowring, Kathleen M. Wooton, Jeffrey M. Amato, Drew S. Coleman, Philip L. Verplanck