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Publications

Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center

Filter Total Items: 2350

Thermotectonic history of the Kluane Ranges and evolution of the eastern Denali Fault Zone in southwestern Yukon, Canada

Exhumation and landscape evolution along strike‐slip fault systems reflect tectonic processes that accommodate and partition deformation in orogenic settings. We present 17 new apatite (U‐Th)/He (He), zircon He, apatite fission‐track (FT), and zircon FT dates from the eastern Denali fault zone (EDFZ) that bounds the Kluane Ranges in Yukon, Canada. The dates elucidate patterns of deformation along

Authors
Robert G. McDermott, Alexis K. Ault, Jonathan S. Caine, Stuart N. Thomson

Mineralogy dictates the initial mechanism of microbial necromass association

Soil organic matter (SOM) improves soil fertility and mitigates disturbance related to climate and land use change. Microbial necromass (the accumulated cellular residues of microorganisms) comprises the majority of soil C, yet the formation and persistence of necromass in relation to mineralogy is poorly understood. We tested whether soil minerals had different microbial necromass association mec
Authors
Courtney Creamer, Andrea L. Foster, Corey Lawrence, Jack McFarland, Marjorie S. Schulz, Mark Waldrop

The presence of antibiotic resistance genes in coastal soil and sediment samples from the eastern seaboard of the USA

Infections from antibiotic resistant microorganisms are considered to be one of the greatest global public health challenges that result in huge annual economic losses. While genes that impart resistance to antibiotics (AbR) existed long before the discovery and use of antibiotics, anthropogenic uses of antibiotics in agriculture, domesticated animals, and humans are known to influence the prevale
Authors
Dale W. Griffin, William Benzel, Shawn C. Fisher, Michael J. Focazio, Luke R. Iwanowicz, Keith A. Loftin, Timothy J. Reilly, Daniel Jones

Sand Creek characterization study for Oncorhynchus clarkii virginalis (Rio Grande Cutthroat Trout), Great Sand Dunes National Park and Preserve, Colorado

The Oncorhynchus clarkii virginalis (Rio Grande cutthroat trout, RGCT) has undergone extensive declines in distribution and population. The RGCT is the southernmost distributed subspecies of cutthroat trout. Native to the Rio Grande Basin in Colorado and New Mexico, the subspecies is also found in the headwaters of the Pecos River and Canadian River basins in New Mexico. Currently, RGCT population
Authors
Ben N. Mcgee, Andrew S. Todd, Kevin K. Terry

Hydrocarbons in upland groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA

Water samples from 50 domestic wells located <1 km (proximal) and >1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic, and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas compared to valleys. CH4-isotope, predrill CH4-concentration,
Authors
Peter B. McMahon, Bruce D. Lindsey, Matthew D. Conlon, Andrew G. Hunt, Kenneth Belitz, Bryant Jurgens, Brian A. Varela

Enhanced landslide mobility by basal liquefaction: the 2014 SR530 (Oso), Washington landslide

Landslide mobility can vastly amplify the consequences of slope failure. As a compelling example, the March 22, 2014 landslide near Oso, Washington (USA) was particularly devastating, traveling across a 1-km+ wide river valley, killing 43 people, destroying dozens of homes, and temporarily closing a well-traveled highway. To resolve causes for the landslide’s behavior and mobility, we conducted d
Authors
Brian D. Collins, Mark E. Reid

Ten-million years of activity within the Eastern California Shear Zone from U-Pb dating of fault-zone opal

Reconstructions of long-term fault activity are essential for understanding both the mechanisms controlling fault behavior and accurate earthquake hazard assessments. Increasing evidence for temporal variations in strain accumulation suggests non-uniform strain rates over a range of historic to geologic timescales. The paucity of long-term records of fault activity has limited our ability to resol
Authors
Perach Nuriel, David M. Miller, Kevin M. Schmidt, Matthew A. Coble, Kate Maher

Topographic change detection at Chalk Cliffs, Colorado, USA, using Airborne LiDAR and UAS-based Structure-from-Motion photogrammetry

The Chalk Cliffs debris-flow site is a small headwater catchment incised into highly fractured and hydrothermally altered quartz monzonite in a semi-arid climate. Over half of the extremely steep basin is exposed bedrock. Debris flows occur multiple times per year in response to rainstorm events, typically during the summer monsoon season. The frequency of debris flows, and the uniformity of the u
Authors
Katherine R Barnhart, Francis K. Rengers, Ghent Jessica N, Gregory E. Tucker, Jeffrey A. Coe, Jason W. Kean, Joel B. Smith, Dennis M. Staley, William Kleiber, Ashton M Wiens

Benthic foraminiferal biotic events related to the Paleocene–Eocene Thermal Maximum along the California Margin

The faunal expression of the Paleocene-Eocene Thermal Maximum (PETM) is well documented in deep-sea sediments. However, few studies have examined continental margin sections, especially active margins. The Moreno and Lodo formations, Central California, were deposited along the eastern margin of a north-south trending forearc basin on the convergent margin of California during the Cretaceous throu
Authors
Kristin McDougall-Reid, Cedric M John

Petrology of volcanic rocks associated with silver-gold (Ag-Au) epithermal deposits in the Tonopah, Divide, and Goldfield Mining Districts, Nevada

Miocene calc-alkaline volcanic rocks, part of the southern segment of the ancestral Cascades magmatic arc, are spatially, temporally, and likely genetically associated with precious metal epithermal deposits in the Tonopah, Divide, and Goldfield Districts of west-central Nevada. In the Tonopah mining district, volcanic rocks include the Mizpah Trachyte, Fraction Tuff, and Oddie Rhyolite; in the Di
Authors
Edward A. du Bray, David John, Joseph Colgan, Peter G. Vikre, Michael A. Cosca, Leah E. Morgan

Variability in shelf sedimentation in response to fluvial sediment supply and coastal erosion over the past 1,000 years in Monterey Bay, CA, United States

Continental shelf environments are uniquely situated to capture some of the most dynamic processes on Earth including climatic variability and anthropogenic modifications to coastal systems. Understanding how these processes have affected sediment delivery and accumulation on the shelf in the past may provide insight into potential changes in the future. To address this, we investigated shelf sedi
Authors
Joseph Carlin, Jason A. Addison, Amy Wagner, Valerie Evelyn Schwartz, Jamie Hayward, Victoria Severin