Publications
Filter Total Items: 1459
Three-dimensional model of the hydrostratigraphy and structure of the area in and around the U.S. Army-Camp Stanley Storage Activity Area, northern Bexar County, Texas Three-dimensional model of the hydrostratigraphy and structure of the area in and around the U.S. Army-Camp Stanley Storage Activity Area, northern Bexar County, Texas
A three-dimensional model of the Camp Stanley Storage Activity area defines and illustrates the surface and subsurface hydrostratigraphic architecture of the military base and adjacent areas to the south and west using EarthVision software. The Camp Stanley model contains 11 hydrostratigraphic units in descending order: 1 model layer representing the Edwards aquifer; 1 model layer...
Authors
Michael P. Pantea, Charles D. Blome, Allan K. Clark
Identifying sources of aeolian mineral dust: Present and past Identifying sources of aeolian mineral dust: Present and past
Aeolian mineral dust is an important component of the Earth’s environmental systems, playing roles in the planetary radiation balance, as a source of fertilizer for biota in both terrestrial and marine realms and as an archive for understanding atmospheric circulation and paleoclimate in the geologic past. Crucial to understanding all of these roles of dust is the identification of dust...
Authors
Daniel R Muhs, Joseph M Prospero, Matthew C Baddock, Thomas E Gill
230Th/U ages Supporting Hanford Site‐Wide Probabilistic Seismic Hazard Analysis 230Th/U ages Supporting Hanford Site‐Wide Probabilistic Seismic Hazard Analysis
This product represents a USGS Administrative Report that discusses samples and methods used to conduct uranium-series isotope analyses and resulting ages and initial 234U/238U activity ratios of pedogenic cements developed in several different surfaces in the Hanford area middle to late Pleistocene. Samples were collected and dated to provide calibration of soil development in surface...
Authors
James B. Paces
Evidence of repeated wildfires prior to human occupation on San Nicolas Island, California Evidence of repeated wildfires prior to human occupation on San Nicolas Island, California
Understanding how early humans on the California Channel Islands might have changed local fire regimes requires a baseline knowledge of the frequency of natural wildfires on the islands prior to human occupation. A sedimentary sequence that was recently discovered in a small canyon on San Nicolas Island contains evidence of at least 24 burn events that date to between ∼37 and 25 ka...
Authors
Jeffrey S. Pigati, John P. McGeehin, Gary L. Skipp, Daniel R. Muhs
Karst in the United States: A digital map compilation and database Karst in the United States: A digital map compilation and database
This report describes new digital maps delineating areas of the United States, including Puerto Rico and the U.S. Virgin Islands, having karst or the potential for development of karst and pseudokarst. These maps show areas underlain by soluble rocks and also by volcanic rocks, sedimentary deposits, and permafrost that have potential for karst or pseudokarst development. All 50 States...
Authors
David J. Weary, Daniel H. Doctor
Key subsurface data help to refine Trinity aquifer hydrostratigraphic units, south-central Texas Key subsurface data help to refine Trinity aquifer hydrostratigraphic units, south-central Texas
The geologic framework and hydrologic characteristics of aquifers are important components for studying the nation’s subsurface heterogeneity and predicting its hydraulic budgets. Detailed study of an aquifer’s subsurface hydrostratigraphy is needed to understand both its geologic and hydrologic frameworks. Surface hydrostratigraphic mapping can also help characterize the spatial...
Authors
Charles D. Blome, Allan K. Clark
Paleoseismology of the Southern Section of the Black Mountains and Southern Death Valley Fault Zones, Death Valley, United States Paleoseismology of the Southern Section of the Black Mountains and Southern Death Valley Fault Zones, Death Valley, United States
The Death Valley Fault System (DVFS) is part of the southern Walker Lane–eastern California shear zone. The normal Black Mountains Fault Zone (BMFZ) and the right-lateral Southern Death Valley Fault Zone (SDVFZ) are two components of the DVFS. Estimates of late Pleistocene-Holocene slip rates and recurrence intervals for these two fault zones are uncertain owing to poor relative age...
Authors
Marsha S. Sohn, Jeffrey R. Knott, Shannon Mahan
A geochronologic framework for the Ziegler Reservoir fossil site, Snowmass Village, Colorado A geochronologic framework for the Ziegler Reservoir fossil site, Snowmass Village, Colorado
The Ziegler Reservoir fossil site near Snowmass Village, Colorado, provides a unique opportunity to reconstruct high-altitude paleoenvironmental conditions in the Rocky Mountains during the last interglacial period. We used four different techniques to establish a chronological framework for the site. Radiocarbon dating of lake organics, bone collagen, and shell carbonate, and in situ...
Authors
Shannon Mahan, Harrison J. Gray, Jeffrey S. Pigati, Jim Wilson, Nathaniel A. Lifton, James B. Paces, Maarten Blaauw
The notion of climate-driven strath-terrace production assessed via dissimilar stream-process response to late Quaternary climate The notion of climate-driven strath-terrace production assessed via dissimilar stream-process response to late Quaternary climate
Previous research results from the Gabilan Mesa are combined with new optically stimulated luminescence (OSL) age estimates and sedimentological analyses with the aim of identifying factors that inhibit climate-driven strath-terrace production, and factors that make possible strath-terrace production independent of climate forcing. The factors are revealed by comparing the...
Authors
Antonio F. Garcia, Shannon Mahan
U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative: 2012 annual report U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative: 2012 annual report
Southwest Wyoming contains abundant energy resources, wildlife, habitat, open spaces, and outdoor recreational opportunities. Although energy exploration and development have been taking place in the region since the late 1800s, the pace of development for fossil fuels and renewable energy increased significantly in the early 2000s. This and the associated urban and exurban development...
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Carleton R. Bern, Laura Biewick, Gregory K. Boughton, Natasha B. Carr, Anna D. Chalfoun, Geneva W. Chong, Melanie L. Clark, Bradford C. Fedy, Katharine Foster, Steven L. Garman, Steve Germaine, Matthew G. Hethcoat, Collin G. Homer, Matthew J. Kauffman, Douglas Keinath, Natalie Latysh, Daniel J. Manier, Robert R. McDougal, Cynthia P. Melcher, Kirk A. Miller, Jessica Montag, Christopher J. Potter, Spencer Schell, Sarah L. Shafer, David B. Smith, Michael J. Sweat, Anna B. Wilson
Carnivore distributions across chaparral habitats exposed to wildfire and rural housing in southern California Carnivore distributions across chaparral habitats exposed to wildfire and rural housing in southern California
Chaparral and coastal sage scrub habitats in southern California support biologically diverse plant and animal communities. However, native plant and animal species within these shrubland systems are increasingly exposed to human-caused wildfires and an expansion of the human–wildland interface. Few data exist to evaluate the effects of fire and anthropogenic pressures on plant and...
Authors
P.A. Schuette, J.E. Diffendorfer, D.H. Deutschman, S. Tremor, W. Spencer
Replacement cost valuation of Northern Pintail (Anas acuta) subsistence harvest in Arctic and sub-Arctic North America Replacement cost valuation of Northern Pintail (Anas acuta) subsistence harvest in Arctic and sub-Arctic North America
Migratory species provide economically beneficial ecosystem services to people throughout their range, yet often, information is lacking about the magnitude and spatial distribution of these benefits at regional scales. We conducted a case study for Northern Pintails (hereafter pintail) in which we quantified regional and sub-regional economic values of subsistence harvest to indigenous
Authors
Joshua H. Goldstein, Wayne E. Thogmartin, Kenneth J. Bagstad, James A. Dubovsky, Brady J. Mattsson, Darius J. Semmens, Laura López-Hoffman, James E. Diffendorfer