Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2485
Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona Bedrock geologic map of Organ Pipe Cactus National Monument and vicinity, southwest Arizona
No abstract available.
Authors
Lisa A. Thompson, Gordon B. Haxel, Donald W. Peterson, Daniel J. May, Richard M. Tosdal, Robert J. Miller, Floyd Gray, Richard A. LeVeque, Paul J. Umhoefer
Subduction zone geometry modulates the megathrust earthquake cycle: Magnitude, recurrence, and variability Subduction zone geometry modulates the megathrust earthquake cycle: Magnitude, recurrence, and variability
Megathrust geometric properties exhibit some of the strongest correlations with maximum earthquake magnitude in global surveys of large subduction zone earthquakes, but the mechanisms through which fault geometry influences subduction earthquake cycle dynamics remain unresolved. Here, we develop 39 models of sequences of earthquakes and aseismic slip (SEAS) on variably-dipping planar and...
Authors
James Burkhardt Biemiller, Alice-Agnes Gabriel, Dave May, Lydia M. Staisch
Aurora: An open-source Python implementation of the EMTF package for magnetotelluric data processing using MTH5 and mt-metadata Aurora: An open-source Python implementation of the EMTF package for magnetotelluric data processing using MTH5 and mt-metadata
The Aurora software package robustly estimates single station and remote reference electromagnetic transfer functions (TFs) from magnetotelluric (MT) time series. Aurora is part of an open-source processing workflow that leverages the self-describing data container MTH5, which in turn leverages the general mt-metadata framework to manage metadata. These pre-existing packages simplify the
Authors
Karl Kappler, Jared R. Peacock, Gary D. Egbert, Andrew Frassetto, Lindsey Heagy, Anna Kelbert, Laura Keyson, Douglas W. Oldenburg, Timothy Ronan, Justin Sweet
Assessing potential effects of oil and gas development activities on groundwater quality near and overlying the Elk Hills and North Coles Levee Oil Fields, San Joaquin Valley, California Assessing potential effects of oil and gas development activities on groundwater quality near and overlying the Elk Hills and North Coles Levee Oil Fields, San Joaquin Valley, California
Groundwater resources are utilized near areas of intensive oil and gas development in California’s San Joaquin Valley. In this study, we examined chemical and isotopic data to assess if thermogenic gas or saline water from oil producing formations have mixed with groundwater near the Elk Hills and North Coles Levee Oil Fields in the southwestern San Joaquin Valley. Major ion...
Authors
John G. Warden, Matthew K. Landon, Michael J. Stephens, Tracy Davis, Janice M. Gillespie, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, David H. Shimabukuro, Riley Gannon, Lyndsay B. Ball
Geochemistry of Archean komatiitic greenstone terranes of the Wyoming Province: Implications for geodynamic setting and mineralization Geochemistry of Archean komatiitic greenstone terranes of the Wyoming Province: Implications for geodynamic setting and mineralization
No abstract available.
Authors
Lisa Joanne Zieman, Jacob Evan Poletti, Michael Jenkins
A multi-methodological approach: Combining textural observations and geochronology to study the J-M Reef Package and its Hanging Wall, Stillwater Complex, Montana A multi-methodological approach: Combining textural observations and geochronology to study the J-M Reef Package and its Hanging Wall, Stillwater Complex, Montana
No abstract available.
Authors
Michael Jenkins, Sam R. Corson, Ennis Geraghty, S.L. Kamo, Heather A. Lowers, James E. Mungall
A Bayesian age from dispersed plagioclase and zircon dates in the Los Chocoyos ash, Central America A Bayesian age from dispersed plagioclase and zircon dates in the Los Chocoyos ash, Central America
The eruption that produced the modern Atitlán caldera in Guatemala has a Volcanic Explosivity Index (VEI) greater than 8, making it the largest of the Quaternary in the Central American Volcanic Arc (CAVA). It generated ∼1220 km3 (730 km3 dense rock equivalent) of dispersed rhyolitic ash and unwelded pyroclastic flow deposits known as the Los Chocoyos ash. Despite its scale, the age of...
Authors
Alec Baudry, Bradley S. Singer, Brian Jicha, Christine E. Jilly-Rehak, Jorge A. Vazquez, C. Brenhin Keller
Controls on stable methane isotope signatures in northern peatlands and potential shifts in signatures under permafrost thaw scenarios Controls on stable methane isotope signatures in northern peatlands and potential shifts in signatures under permafrost thaw scenarios
Northern peatlands are a globally significant source of methane (CH4), and emissions are projected to increase due to warming and permafrost loss. Understanding the microbial mechanisms behind patterns in CH4 production in these systems will be key to predicting annual emissions changes, with stable carbon isotopes (δ13C-CH4) being a powerful tool for characterizing these drivers. Given...
Authors
McKenzie A. Kuhn, Ruth K. Varner, Carmody K. McCalley, Clarice R. Perryman, Mika Aurela, Sophia A. Burke, Jeffrey Chanton, Patrick Crill, Jessica DelGreco, Jia Deng, Liam Heffernan, Christina Herrick, Suzanne B. Hodgkins, Cheristy P. Jones, Sari Juutinen, Evan S. Kane, Louis J. Lamit, Tuula Larmola, Erik Lilleskov, David Olefeldt, Michael W. Palace, Virginia I. Rich, Christopher Schulze, Joanne H. Shorter, Franklin Sullivan, Oliver Sonnentag, Merritt R. Turetsky, Mark Waldrop
New 10Be-26Al isochron burial dating informs the Pliocene and Pleistocene evolution of the lower Colorado River, southwestern United States New 10Be-26Al isochron burial dating informs the Pliocene and Pleistocene evolution of the lower Colorado River, southwestern United States
Four new 10Be-26Al isochron burial ages ranging from 4.4 to 2 Ma on ancestral Colorado River deposits in the lower Colorado River corridor (LCRC) help constrain the river’s evolution during the Pliocene and early Pleistocene. They help fill a gap between previous work that focused on older and younger deposits: Older dated deposits include the 5 Ma Bouse Formation, which records the...
Authors
Yeong Bae Seong, Ryan S. Crow, Kyle House, Keith A. Howard, Cho-Hee Lee, Byong Yong Yu
Thermal and hydrological limitations on modeling carbon dynamics at wetland sites of discontinuous and continuous permafrost extent Thermal and hydrological limitations on modeling carbon dynamics at wetland sites of discontinuous and continuous permafrost extent
Accurate representation of cryohydrological processes is fundamental for biosphere models, particularly at high-latitudes, given their influence on carbon and permafrost dynamics in carbon-rich peatlands and wetlands. This study analyzes site-level simulations in moist and wet drainage conditions in continuous or discontinuous permafrost regions, using a terrestrial ecosystem model DVM...
Authors
Benjamin C. Maglio, Ruth Rutter, Tobey Carman, Colin W. Edgar, Eugénie S. Euskirchen, Hélène Genet, Andrew Mullen, Valeria Briones, Elchin Jafarov, Kristen L. Manies
Dissolved arsenic concentrations in surface waters within the upper portions of the Klamath River Basin, Oregon and California Dissolved arsenic concentrations in surface waters within the upper portions of the Klamath River Basin, Oregon and California
Arsenic toxicity is an environmental health problem. Levels of arsenic in surface waters at some locations in the Klamath River Basin in southern Oregon and northern California can exceed the U.S. Environmental Protection Agency (EPA) standard for drinking water. There are both anthropogenic and natural sources of arsenic. The Klamath River Basin consists primarily of volcanic deposits...
Authors
Marie Noele Croteau, Brent R. Topping, Rick A. Carlson
Using surficial geologic maps, vegetation, and monitoring to address erosion impacts from grazing in Channel Islands National Park, California Using surficial geologic maps, vegetation, and monitoring to address erosion impacts from grazing in Channel Islands National Park, California
Employing a map-unit classification scheme based on geomorphic process and age, the U.S. Geological Survey (USGS) mapped Quaternary surficial deposits of the five islands comprising Channel Islands National Park (CHIS), California, as no such maps previously existed. Mapping was motivated through an agreement with the National Park Service (NPS) to aid natural resource assessments...
Authors
Kevin Schmidt, Scott A. Minor, Kathryn McEachern