Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2543
The age of the Steens reversal and the Columbia River Basalt Group The age of the Steens reversal and the Columbia River Basalt Group
The Columbia River Basalt Group (CRBG) eruptions have a well-defined relative magnetostratigraphy but have not been definitively correlated to the geomagnetic polarity time scale. 40Ar/39Ar ages are presented from lavas erupted in the R0 through N1magnetozones of the CRBG and in the transition between R0 and N0. Four ages from transitionally magnetized lava flows at Steens Mountain...
Authors
Nicholas A. Jarboe, Robert S. Coe, Paul R. Renne, Jonathan M. G. Glen
In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids In vitro studies evaluating leaching of mercury from mine waste calcine using simulated human body fluids
In vitro bioaccessibility (IVBA) studies were carried out on samples of mercury (Hg) mine-waste calcine (roasted Hg ore) by leaching with simulated human body fluids. The objective was to estimate potential human exposure to Hg due to inhalation of airborne calcine particulates and hand-to-mouth ingestion of Hg-bearing calcines. Mine waste calcines collected from Hg mines at Almadén...
Authors
John E. Gray, Geoffrey S. Plumlee, Suzette A. Morman, Pablo L. Higueras, James G. Crock, Heather A. Lowers, Mark L. Witten
Are modern geothermal waters in northwest Nevada forming epithermal gold deposits? Are modern geothermal waters in northwest Nevada forming epithermal gold deposits?
Hydrothermal systems currently are active near some gold deposits in northwestern Nevada. Possible links of these modern systems to gold mineralization were evaluated by chemically and isotopically analyzing water samples from the Brady, Dixie Valley, Humboldt House, San Emidio-Empire, Soda Lake, and Wabuska geothermal areas. In addition, quartz veins from Humboldt House and the adjacent...
Authors
George N. Breit, Andrew G. Hunt, Ruth E. Wolf, Alan E. Koenig, Richard Fifarek, Mark F. Coolbaugh
Geometry and kinematics of the eastern Lake Mead fault system in the Virgin Mountains, Nevada and Arizona Geometry and kinematics of the eastern Lake Mead fault system in the Virgin Mountains, Nevada and Arizona
The Lake Mead fault system is a northeast-striking, 130-km-long zone of left-slip in the southeast Great Basin, active from before 16 Ma to Quaternary time. The northeast end of the Lake Mead fault system in the Virgin Mountains of southeast Nevada and northwest Arizona forms a partitioned strain field comprising kinematically linked northeast-striking left-lateral faults, north-striking...
Authors
Sue Beard, David J. Campagna, R. Ernest Anderson
Kinetics of selenium release in mine waste from the Meade Peak Phosphatic Shale, Phosphoria Formation, Wooley Valley, Idaho, USA Kinetics of selenium release in mine waste from the Meade Peak Phosphatic Shale, Phosphoria Formation, Wooley Valley, Idaho, USA
Phosphorite from the Meade Peak Phosphatic Shale member of the Permian Phosphoria Formation has been mined in southeastern Idaho since 1906. Dumps of waste rock from mining operations contain high concentrations of Se which readily leach into nearby streams and wetlands. While the most common mineralogical residence of Se in the phosphatic shale is elemental Se, Se(0), Se is also an...
Authors
Lisa L. Stillings, Michael C. Amacher
Algal blooms and "Marine snow": Mechanisms that enhance preservation of organic carbon in ancient fine-grained sediments Algal blooms and "Marine snow": Mechanisms that enhance preservation of organic carbon in ancient fine-grained sediments
Combined petrographic and geochemical methods are used to investigate the microfabrics present in thin sections prepared from representative organic carbon-rich mudstones collected from three successions (the Kimmeridge Clay Formation, the Jet Rock Member of the Whitby Mudstone Formation, and the pebble shale and Hue Shale). This study was initiated to determine how organic carbon-rich...
Authors
Joe H.S. Macquaker, Margaret A. Keller, Sarah J. Davies
Discussion on remote sensing for aquatic monitoring Discussion on remote sensing for aquatic monitoring
The special session on Remote Sensing for Aquatic Resource Monitoring concluded with an expert panel discussion. Panel members were Jennifer Bountry (hydraulic engineer, Bureau of Reclamation), Mimi D’Iorio (GIS analyst and database manager, National Oceanic and Atmospheric Administration), Russ Faux (president, Watershed Sciences, Inc.), Steve Lanigan (team leader, Aquatic and Riparian
Authors
Ralph A. Haugerud
First ever release of USGS offshore arctic resource assessment First ever release of USGS offshore arctic resource assessment
No abstract available.
Authors
Donald L. Gautier, Kenneth J. Bird, Ronald Charpentier, Arthur Grantz, David W. Houseknecht, Timothy R. Klett, Thomas E. Moore, Janet K. Pitman, Christopher J. Schenk, John H. Schuenemeyer, Kai Sorensen, Marilyn E. Tennyson
A Collection of Chemical, Mineralogical, and Stable Isotopic Compositional Data for Green River Oil Shale from Depositional Center Cores in Colorado, Utah, and Wyoming A Collection of Chemical, Mineralogical, and Stable Isotopic Compositional Data for Green River Oil Shale from Depositional Center Cores in Colorado, Utah, and Wyoming
For over half a century, the U.S. Geological Survey and collaborators have conducted stratigraphic and geochemical studies on the Eocene Green River Formation, which is known to contain large oil shale resources. Many of the studies were undertaken in the 1970s during the last oil shale boom. One such study analyzed the chemistry, mineralogy, and stable isotopy of the Green River...
Authors
Michele L.W. Tuttle
Assessment of undiscovered oil and gas in the Arctic Assessment of undiscovered oil and gas in the Arctic
Among the greatest uncertainties in future energy supply and a subject of considerable environmental concern is the amount of oil and gas yet to be found in the Arctic. By using a probabilistic geology-based methodology, the United States Geological Survey has assessed the area north of the Arctic Circle and concluded that about 30% of the world’s undiscovered gas and 13% of the world’s
Authors
Donald L. Gautier, Kenneth J. Bird, Ronald Charpentier, Arthur Grantz, David W. Houseknecht, Timothy R. Klett, Thomas E. Moore, Janet K. Pitman, Christopher J. Schenk, John H. Schuenemeyer, Kai Sorenson, Marilyn E. Tennyson, Zenon C. Valin, Craig J. Wandrey
Helicopter Electromagnetic and Magnetic Geophysical Survey Data for Portions of the North Platte River and Lodgepole Creek, Nebraska, June 2008 Helicopter Electromagnetic and Magnetic Geophysical Survey Data for Portions of the North Platte River and Lodgepole Creek, Nebraska, June 2008
This report is a release of digital data from a helicopter electromagnetic and magnetic survey that was conducted during June 2008 in areas of western Nebraska as part of a joint hydrologic study by the North Platte Natural Resource District, South Platte Natural Resource District, and U.S. Geological Survey. The objective of the contracted survey, conducted by Fugro Airborne, Ltd., was...
Authors
Bruce D. Smith, Jared D. Abraham, James C. Cannia, Patricia Hill
A preliminary, full spectrum, magnetic anomaly grid of the United States with improved long wavelengths for studying continental dynamics: A website for distribution of data A preliminary, full spectrum, magnetic anomaly grid of the United States with improved long wavelengths for studying continental dynamics: A website for distribution of data
Under an initiative started by Thomas G. Hildenbrand of the U.S. Geological Survey, we have improved the long-wavelength (50-2,500 km) content of the regional magnetic anomaly compilation for the conterminous United States by utilizing a nearly homogeneous set of National Uranium Resource Evaluation (NURE) magnetic surveys flown from 1975 to 1981. The surveys were flown in quadrangles of...
Authors
D. Ravat, Carol A. Finn, P. Hill, R. Kucks, J. Phillips, R. Blakely, C. Bouligand, T. Sabaka, A. Elshayat, A. Aref, E. Elawadi