Publications
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Assessing landscape change and processes of recurrence, replacement, and recovery in the Southeastern Coastal Plains, USA
The processes of landscape change are complex, exhibiting spatial variability as well as linear, cyclical, and reversible characteristics. To better understand the various processes that cause transformation, a data aggregation, validation, and attribution approach was developed and applied to an analysis of the Southeastern Coastal Plains (SECP). The approach integrates information from available
Authors
Mark A. Drummond, Michael P. Stier, Roger F. Auch, Janis L. Taylor, Glenn E. Griffith, D. J. Hester, Jodi L. Riegle, Christopher E. Soulard, Jamie L. McBeth
Preliminary geophysical interpretations of regional subsurface geology near the Questa Mine Tailing Facility and Guadalupe Mountain, Taos County, New Mexico
This report presents geophysical interpretations of regional subsurface geology in the vicinity of the Tailing Facility of the Questa Mine near Guadalupe Mountain, Taos County, New Mexico, in cooperation with the New Mexico Environment Department. The interpretations were developed from aeromagnetic data, regional gravity data, data from four ground magnetic traverses, geologic mapping, a digital
Authors
V. J. S. Grauch, Benjamin J. Drenth, Ren A. Thompson, Paul W. Bauer
Resilience of ponderosa and lodgepole pine forests to mountain pine beetle disturbance and limited regeneration
After causing widespread mortality in lodgepole pine forests in North America, the mountain pine beetle (MPB) has recently also affected ponderosa pine, an alternate host species that may have different levels of resilience to this disturbance. We collected field data in ponderosa pine- and lodgepole pine-dominated forests attacked by MPB in Colorado and then simulated stand growth over 200 years
Authors
Jenny S. Briggs, Todd Hawbaker, Don Vandendriesche
U.S. Geological Survey science for the Wyoming Landscape Conservation Initiative—2014 annual report
This is the seventh report produced by the U.S. Geological Survey (USGS) for the Wyoming Landscape Conservation Initiative (WLCI) to detail annual activities conducted by the USGS for addressing specific management needs identified by WLCI partners. In FY2014, there were 26 projects, including a new one that was completed, two others that were also completed, and several that entered new phases or
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Timothy T. Bartos, Laura R Biewick, Gregory K. Boughton, Anna D. Chalfoun, Geneva W. Chong, Marie K. Dematatis, Cheryl A. Eddy-Miller, Steven L. Garman, Steve Germaine, Collin G. Homer, Christopher Huber, Matthew J. Kauffman, Natalie Latysh, Daniel J. Manier, Cynthia P. Melcher, Alexander Miller, Kirk A. Miller, Edward M. Olexa, Spencer Schell, Annika W. Walters, Anna B. Wilson, Teal B. Wyckoff
Lithostratigraphic, borehole-geophysical, hydrogeologic, and hydrochemical data from the East Bay Plain, Alameda County, California
The U.S. Geological Survey, in cooperation with the East Bay Municipal Utility District, carried out an investigation of aquifer-system deformation associated with groundwater-level changes at the Bayside Groundwater Project near the modern San Francisco Bay shore in San Lorenzo, California. As a part of the Bayside Groundwater Project, East Bay Municipal Utility District proposed an aquifer stora
Authors
Michelle Sneed, Patricia v.P. Orlando, James W. Borchers, Rhett R. Everett, Michael Solt, Mary McGann, Heather Lowers, Shannon Mahan
Regional variability in dust-on-snow processes and impacts in the Upper Colorado River Basin
Dust deposition onto mountain snow cover in the Upper Colorado River Basin frequently occurs in the spring when wind speeds and dust emission peaks on the nearby Colorado Plateau. Dust loading has increased since the intensive settlement in the western USA in the mid 1880s. The effects of dust-on-snow have been well studied at Senator Beck Basin Study Area (SBBSA) in the San Juan Mountains, CO, th
Authors
S. McKenzie Skiles, Thomas H. Painter, Jayne Belnap, Lacey Holland, Richard L. Reynolds, Harland L. Goldstein, J. Lin
Early Holocene Great Salt Lake
Shorelines and surficial deposits (including buried forest-floor mats and organic-rich wetland sediments) show that Great Salt Lake did not rise higher than modern lake levels during the earliest Holocene (11.5–10.2 cal ka BP; 10–9 14C ka BP). During that period, finely laminated, organic-rich muds (sapropel) containing brine-shrimp cysts and pellets and interbedded sodium-sulfate salts were depos
Authors
Charles G. Oviatt, David B. Madsen, David M. Miller, Robert S. Thompson, John P. McGeehin
Evidence of a higher late-Holocene treeline along the Continental Divide in central Colorado
Using a combination of 23 radiocarbon ages and annual ring counts from 18 Rocky Mountain bristlecone pine (Pinus aristata) remnants above the local present-day limits, a period of higher treeline has been determined for two sites near the Continental Divide in central Colorado. The highest remnants were found about 30 m above live bristlecone pines of similar size. The majority of the remnants, co
Authors
Paul E. Carrara, John McGeehin
Comparing ecoregional classifications for natural areas management in the Klamath Region, USA
We compared three existing ecoregional classification schemes (Bailey, Omernik, and World Wildlife Fund) with two derived schemes (Omernik Revised and Climate Zones) to explore their effectiveness in explaining species distributions and to better understand natural resource geography in the Klamath Region, USA. We analyzed presence/absence data derived from digital distribution maps for trees, amp
Authors
Daniel A. Sarr, Andrew Duff, Eric C. Dinger, Sarah L. Shafer, Michael Wing, Nathaniel E. Seavy, John D. Alexander
Paleodischarge of the Mojave River, southwestern U.S.A, investigated with single-pebble measurements of 10Be
The paleohydrology of ephemeral stream systems is an important constraint on paleoclimatic conditions in arid environments, but remains difficult to constrain quantitatively. For example, sedimentary records of the size and extent of pluvial lakes in the Mojave Desert have been used as a proxy for Quaternary climate variability. Although the delivery mechanisms of this additional water are still b
Authors
Andrew J. Cyr, David M. Miller, Shannon A. Mahan
Comment on “The role of interbasin groundwater transfers in geologically complex terranes, demonstrated by the Great Basin in the western United States”: report published in Hydrogeology Journal (2014) 22:807–828, by Stephen T. Nelson and Alan L. Mayo
The subject article (Nelson and Mayo 2014) presents an overview of previous reports of interbasin flow in the Great Basin of the western United States. This Comment is presented by authors of a cited study (comprising chapters in one large report) on the Great Basin carbonate and alluvial aquifer system (GBCAAS; Heilweil and Brooks 2011; Masbruch et al. 2011; Sweetkind et al. 2011a, b), who agree
Authors
Melissa D. Masbruch, Lynette E. Brooks, Victor M. Heilweil, Donald S. Sweetkind
Geologic history of the Black Hills caves, South Dakota
Cave development in the Madison aquifer of the Black Hills has taken place in several stages. Mississippian carbonates first underwent eogenetic (early diagenetic) reactions with interbedded sulfates to form breccias and solution voids. Later subaerial exposure allowed oxygenated meteoric water to replace sulfates with calcite and to form karst and small caves. All were later buried by ~2 km of Pe
Authors
Arthur N. Palmer, Margaret Palmer, James B. Paces