Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2533
Finding concealed active faults: Extending the southern Whidbey Island fault across the Puget Lowland, Washington Finding concealed active faults: Extending the southern Whidbey Island fault across the Puget Lowland, Washington
The southern Whidbey Island fault zone (SWIF), as previously mapped using borehole data, potential field anomalies, and marine seismic reflection surveys, consists of three subparallel, northwest trending strands extending ∼100 km from near Vancouver Island to the northern Puget Lowland. East of Puget Sound, the SWIF makes landfall between the cities of Seattle and Everett but is...
Authors
Brian L. Sherrod, Richard J. Blakely, Craig S. Weaver, Harvey M. Kelsey, Elizabeth Barnett, Lee Liberty, Karen L. Meagher, Kristin Pape
Preliminary Gravity and Ground Magnetic Data in the Arbuckle Uplift near Sulphur, Oklahoma Preliminary Gravity and Ground Magnetic Data in the Arbuckle Uplift near Sulphur, Oklahoma
Improving knowledge of the geology and geophysics of the Arbuckle Uplift in south-central Oklahoma is a goal of the Framework Geology of Mid-Continent Carbonate Aquifers project sponsored by the United States Geological Survey (USGS) National Cooperative Geologic Mapping Program (NCGMP). In May 2007, we collected ground magnetic and gravity observations in the Hunton Anticline region of...
Authors
Daniel S. Scheirer, Essam Aboud
Magmatic and tectonic evolution of the Caetano caldera, north-central Nevada: A tilted, mid-Tertiary eruptive center and source of the Caetano Tuff Magmatic and tectonic evolution of the Caetano caldera, north-central Nevada: A tilted, mid-Tertiary eruptive center and source of the Caetano Tuff
The Caetano Tuff is a late Eocene, rhyolite ash-flow tuff that crops out within an ∼90-km-long, east-west–trending belt in north-central Nevada, previously interpreted as an elongate graben or “volcano-tectonic trough.” New field, petrographic, geochemical, and geochronologic data show that: (1) the east half of the “trough” is actually the Caetano caldera, formed by eruption of the...
Authors
David A. John, Christopher D. Henry, Joseph P. Colgan
A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada A prominent geophysical feature along the northern Nevada rift and its geologic implications, north-central Nevada
We consider the origin and character of a prominent large-scale geophysical feature in north-central Nevada that is coincident with the western margin of the northern Nevada rift—a mid-Miocene rift that includes mafic dike swarms and associated volcanic rocks expressed by a NNW-striking magnetic anomaly. The geophysical feature also correlates with mid-Miocene epithermal gold deposits...
Authors
David A. Ponce, Jonathan M.G. Glen
Large-magnitude Miocene extension of the Eocene Caetano caldera, Shoshone and Toiyabe Ranges, Nevada Large-magnitude Miocene extension of the Eocene Caetano caldera, Shoshone and Toiyabe Ranges, Nevada
Because major mineral deposits in north-central Nevada predate significant Basin and Range extension, a detailed understanding of the timing and kinematics of extensional faulting is necessary to place these deposits in their original structural context. The complexity of pre-Cenozoic deformation in northern Nevada makes restoring Basin and Range faulting difficult without locating well...
Authors
Joseph P. Colgan, David A. John, Christopher D. Henry, Robert J. Fleck
Analysis of a spatial point pattern: Examining the damage to pavement and pipes in Santa Clara Valley resulting from the Loma Prieta earthquake Analysis of a spatial point pattern: Examining the damage to pavement and pipes in Santa Clara Valley resulting from the Loma Prieta earthquake
This report describes some simple spatial statistical methods to explore the relationships of scattered points to geologic or other features, represented by points, lines, or areas. It also describes statistical methods to search for linear trends and clustered patterns within the scattered point data. Scattered points are often contained within irregularly shaped study areas...
Authors
G. A. Phelps
Geology: Chapter 2 Geology: Chapter 2
No abstract available.
Authors
Richard G. Stanley, G. E. Weber
Cyanide speciation at four gold leach operations undergoing remediation Cyanide speciation at four gold leach operations undergoing remediation
Analyses have been made of 81 effluents from four gold leach operations in various stages of remediation to identify the most-persistent cyanide species. Total cyanide and weak acid-dissociable (WAD) cyanide were measured using improved methods, and metals known to form stable cyanocomplexes were also measured. Typically, total cyanide greatly exceeded WAD indicating that cyanide was...
Authors
Craig A. Johnson, David J. Grimes, Reinhard W. Leinz, Robert O. Rye
Millimeter-scale geologic mapping using field spectroscopy techniques Millimeter-scale geologic mapping using field spectroscopy techniques
No abstract available.
Authors
David C. Buesch, Daniel E. Ragona, Mark C. Helmlinger
Quickly erupted volcanic sections of the Steens Basalt, Columbia River Basalt Group: Secular variation, tectonic rotation, and the Steens Mountain reversal Quickly erupted volcanic sections of the Steens Basalt, Columbia River Basalt Group: Secular variation, tectonic rotation, and the Steens Mountain reversal
The Steens Basalt, now considered part of the Columbia River Basalt Group (CRBG), contains the earliest eruptions of this magmatic episode. Lava flows of the Steens Basalt cover about 50,000 km2 of the Oregon Plateau in sections up to 1000 m thick. The large number of continuously exposed, quickly erupted lava flows (some sections contain over 200 flows) allows for small loops in the...
Authors
Nicholas A. Jarboe, Robert S. Coe, Paul R. Renne, Jonathan M. G. Glen, Edward A. Mankinen
Structures controlling geothermal circulation identified through gravity and magnetic transects, Surprise Valley, California, northwestern Great Basin Structures controlling geothermal circulation identified through gravity and magnetic transects, Surprise Valley, California, northwestern Great Basin
No abstract available.
Authors
Jonathan M.G. Glen, Anne E. Egger, David A. Ponce