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
Speciation of arsenic, selenium, and chromium in wildfire impacted soils and ashes
In 2007-09, California experienced several large wildfires that damaged large areas of forest and destroyed many homes and buildings. The U.S. Geological Survey collected samples from the Harris, Witch, Grass Valley, Ammo, Santiago, Canyon, Jesusita, and Station fires for testing to identify any possible characteristics of the ashes and soils from burned areas that may be of concern for their impa
Authors
Ruth E. Wolf, Todd M. Hoefen, Philip L. Hageman, Suzette A. Morman, Geoffrey S. Plumlee
Detection and mapping of hydrocarbon deposits on Titan
We report the identification of compounds on Titan's surface by spatially resolved imaging spectroscopy methods through Titan's atmosphere, and set upper limits to other organic compounds. We present evidence for surface deposits of solid benzene (C6H6), solid and/or liquid ethane (C2H6), or methane (CH4), and clouds of hydrogen cyanide (HCN) aerosols using diagnostic spectral features in data fro
Authors
Roger N. Clark, J. M. Curchin, Jason W. Barnes, Ralf Jaumann, Laurence A. Soderblom, Dale P. Cruikshank, Robert H. Brown, Sebastien Rodriguez, Jonathan Lunine, Katrin Stephan, Todd M. Hoefen, Stephane Le Mouelic, Christophe Sotin, Kevin H. Baines, Bonnie J. Buratti, Philip D. Nicholson
The tectono-thermal evolution of the Waterbury dome, western Connecticut, based on U-Pb and 40Ar/39Ar ages
The Waterbury dome, located in the Rowe-Hawley zone in western Connecticut, is a triple window exposing three terranes: parautochthonous or allochthonous peri-Laurentian rocks in its lowest level 1, allochthonous rocks of the Rowe-Hawley zone in its middle level 2, and allochthonous cover rocks, including Silurian-Devonian rocks of the Connecticut Valley Gaspé trough, in its highest level 3. Level
Authors
Craig Dietsch, Michael J. Kunk, John Aleinikoff, John F. Sutter
Stratiform chromite deposit model
Stratiform chromite deposits are of great economic importance, yet their origin and evolution remain highly debated. Layered igneous intrusions such as the Bushveld, Great Dyke, Kemi, and Stillwater Complexes, provide opportunities for studying magmatic differentiation processes and assimilation within the crust, as well as related ore-deposit formation. Chromite-rich seams within layered intrusio
Authors
Ruth F. Schulte, Ryan D. Taylor, Nadine M. Piatak, Robert R. Seal
USGS exploration geochemistry studies at the Pebble porphyry Cu-Au-Mo deposit, Alaska— Pdf of presentation
From 2007 through 2010, scientists in the U.S. Geological Survey (USGS) have been conducting exploration-oriented geochemical and geophysical studies in the region surrounding the giant Pebble porphyry Cu-Au-Mo deposit in southwestern Alaska. The Cretaceous Pebble deposit is concealed under tundra, glacial till, and Tertiary cover rocks, and is undisturbed except for numerous exploration drill hol
Authors
Robert G. Eppinger, Karen D. Kelley, David L. Fey, Stuart A. Giles, Burke J. Minsley, Steven M. Smith
Stream-sediment samples reanalyzed for major, rare earth, and trace elements from seven 1:250,000-scale quadrangles, south-central Alaska, 2007-09
During the 1960s through the 1980s, the U.S. Geological Survey conducted reconnaissance geochemical surveys of drainage basins throughout most of the Iliamna, Lake Clark, Lime Hills, and Talkeetna 1:250,000-scale quadrangles and parts of the McGrath, Seldovia, and Tyonek 1:250,000-scale quadrangles in Alaska. These geochemical surveys provide data necessary to assess the potential for undiscovered
Authors
Bruce M. Gamble, Elizabeth A. Bailey, Nora B. Shew, Keith A. Labay, Jeanine M. Schmidt, Richard M. O'Leary, David E. Detra
Glimpses of East Antarctica: Aeromagnetic and satellite magnetic view from the central Transantarctic Mountains of East Antarctica
Aeromagnetic and satellite magnetic data provide glimpses of the crustal architecture within the Ross Sea sector of the enigmatic, ice-covered East Antarctic shield critical for understanding both global tectonic and climate history. In the central Transantarctic Mountains (CTAM), exposures of Precambrian basement, coupled with new high-resolution magnetic data, other recent aeromagnetic transects
Authors
Carol A. Finn, John W. Goodge
Analytical results for municipal biosolids samples from a monitoring program near Deer Trail, Colorado (U.S.A.), 2009
Since late 1993, Metro Wastewater Reclamation District of Denver, a large wastewater treatment plant in Denver, Colo., has applied Grade I, Class B biosolids to about 52,000 acres of nonirrigated farmland and rangeland near Deer Trail, Colo., U.S.A. In cooperation with the Metro District in 1993, the U.S. Geological Survey began monitoring groundwater at part of this site. In 1999, the Survey bega
Authors
J. G. Crock, D. B. Smith, T. J. B. Yager, C. J. Berry, M. G. Adams
Magnetotelluric survey to characterize the Sunnyside porphyry copper system in the Patagonia Mountains, Arizona
The Sunnyside porphyry copper system is part of the concealed San Rafael Valley porphyry system located in the Patagonia Mountains of Arizona. The U.S. Geological Survey is conducting a series of multidisciplinary studies as part of the Assessment Techniques for Concealed Mineral Resources project. To help characterize the size and resistivity of the mineralized area beneath overburden, a regional
Authors
Brian D. Rodriguez, Jay A. Sampson
Geology, geochemistry, and genesis of the Greens Creek massive sulfide deposit, Admiralty Island, southeastern Alaska
In 1996, a memorandum of understanding was signed by representatives of the U.S. Geological Survey and Kennecott Greens Creek Mining Company to initiate a cooperative applied research project focused on the Greens Creek massive sulfide deposit in southeastern Alaska. The goals of the project were consistent with the mandate of the U.S. Geological Survey Mineral Resources Program to maintain a lead
Authors
Cliff D. Taylor, Craig A. Johnson
Porphyry copper deposit model
This report contains a revised descriptive model of porphyry copper deposits (PCDs), the world's largest source (about 60 percent) and resource (about 65 percent) of copper and a major source of molybdenum, gold and silver. Despite relatively low grades (average 0.44 percent copper in 2008), PCDs have significant economic and societal impacts due to their large size (commonly hundreds of millions
Authors
Robert A. Ayuso, Mark D. Barton, Richard J. Blakely, Robert J. Bodnar, John H. Dilles, Floyd Gray, Fred T. Graybeal, John L. Mars, Darcy McPhee, Robert R. Seal, Ryan D. Taylor, Peter G. Vikre
Geochemical data for Colorado soils: Results from the 2006 state-scale geochemical survey
In 2006, soil samples were collected at 960 sites (1 site per 280 square kilometers) throughout the state of Colorado. These samples were collected from a depth of 0-15 centimeters and, following a near-total multi-acid digestion, were analyzed for a suite of more than 40 major and trace elements. The resulting data set provides a baseline for the natural variation in soil geochemistry for Colorad
Authors
David B. Smith, Karl J. Ellefsen, James E. Kilburn