Publications
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Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California
During the late Pleistocene, emergent groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the ge
Authors
Jeffrey S. Pigati, David M. Miller, Jordon E. Bright, Shannon Mahan, Jeffrey C. Nekola, James B. Paces
Responses of wind erosion to climate-induced vegetation changes on the Colorado Plateau
Projected increases in aridity throughout the southwestern United States due to anthropogenic climate change will likely cause reductions in perennial vegetation cover, which leaves soil surfaces exposed to erosion. Accelerated rates of dust emission from wind erosion have large implications for ecosystems and human well-being, yet there is poor understanding of the sources and magnitude of dust e
Authors
Seth M. Munson, Jayne Belnap, Gregory S. Okin
Cosmogenic nuclide and uranium-series dating of old, high shorelines in the western Great Basin, USA
Closed-basin pluvial lakes are sensitive recorders of effective moisture, and they provide a terrestrial signal of climate change that can be compared to marine and ice records of glacial-interglacial cycles. Although the most recent deep-lake cycle in the western Great Basin (at ca. 16 ka) has been studied intensively, comparatively little is known about the longer-term Quaternary lacustrine hist
Authors
G. Kurth, F. M. Phillips, Marith C. Reheis, J.L. Redwine, James B. Paces
Chronology, sedimentology, and microfauna of groundwater discharge deposits in the central Mojave Desert, Valley Wells, California
During the late Pleistocene, emergent groundwater supported persistent and long-lived desert wetlands in many broad valleys and basins in the American Southwest. When active, these systems provided important food and water sources for local fauna, supported hydrophilic and phreatophytic vegetation, and acted as catchments for eolian and alluvial sediments. Desert wetlands are represented in the ge
Authors
Jeffrey S. Pigati, David Miller, J.E. Bright, Shannon A. Mahan, J.C. Nekola, James B. Paces
The angus mammoth: A decades-old scientific controversy resolved
The Angus Mammoth site in south-central Nebraska has been controversial since its discovery in 1931 when a fluted artifact was reported to be associated with the mammoth. For nearly 80 years it has not been known if Angus was a paleontological site predating the human occupation of North America as has been asserted by some geologists and paleontologists, or an archaeological site dating to the la
Authors
Steven R. Holen, D.W. May, Shannon A. Mahan
Barrier island response to late Holocene climate events, North Carolina, USA
The Outer Banks barrier islands of North Carolina, USA, contain a geologic record of inlet activity that extends from ca. 2200 cal yr BP to the present, and can be used as a proxy for storm activity. Optically stimulated luminescence (OSL) dating (26 samples) of inlet-fill and flood tide delta deposits, recognized in cores and geophysical data, provides the basis for understanding the chronology o
Authors
D. J. Mallinson, C. W. Smith, S. Mahan, S.J. Culver, K. McDowell
The use of scenario analysis to assess water ecosystem services in response to future land use change in the Willamette River Basin, Oregon
Human pressures on the natural resources of the United States have resulted in many unintended changes in our ecosystems, e.g., loss of biodiversity, habitat degradation, increases in the number of endangered species, and increases in contamination and water pollution. Environmental managers are concerned about broad-scale changes in land use and landscape pattern and their cumulative impact on hy
Authors
M. Hernandez, W. G. Kepner, D. G. Goodrich, Darius J. Semmens
Hydrothermal alteration of the Late Eocene Caetano ash-flow caldera, north-central Nevada: A field and ASTER remote sensing study
Geologic mapping and analysis of ASTER remote sensing data were used to define the effects of a large hydrothermal system in the 12–18 by 22 km Caetano caldera. The caldera formed at ~33.8Ma during eruption of >1100km3 of the rhyolitic Caetano Tuff that left a 1 km deep basin which was partly filled by a lake. Magma resurgence resulted in shallow(<1 km) emplacement of the Redrock Canyon granite po
Authors
David John, Barnaby W. Rockwell, Christopher D. Henry, Joseph Colgan
Social Values for Ecosystem Services (SolVES): using GIS to include social values information in ecosystem services assessments
Ecosystem services can be defined in various ways; simply put, they are the benefits provided by nature, which contribute to human well-being. These benefits can range from tangible products such as food and fresh water to cultural services such as recreation and esthetics. As the use of these benefits continues to increase, additional pressures are placed on the natural ecosystems providing them.
Authors
B.C. Sherrouse, D.J. Semmens
Assessment of goods and valuation of ecosystem services (AGAVES) San Pedro River Basin, United States and Mexico
A consortium of federal, academic, and nongovernment organization (NGO) partners have established a collaborative research enterprise in the San Pedro River Basin to develop methods, standards, and tools to assess and value ecosystem goods and services. The central premise of ecosystem services research is that human condition is intrinsically linked to the environment. Human health and well-being
Authors
Darius J. Semmens, William Kepner, David Goodrich
Characterization of geologic deposits in the vicinity of US Ecology, Amargosa Basin, southern Nevada
Multiple approaches have been applied to better understand the characteristics of geologic units exposed at the surface and buried at depth in the vicinity of US Ecology (USE), a low-level commercial waste site in the northern Amargosa Desert, Nevada. Techniques include surficial geologic mapping and interpretation of the subsurface using borehole data. Dated deposits at depth were used to estimat
Authors
Emily M. Taylor
U.S. Geological Survey Science for the Wyoming Landscape Conservation Initiative-2009 Annual Report
This is the second report produced by the U.S. Geological Survey (USGS) for the Wyoming Landscape Conservation Initiative (WLCI) to detail annual work activities. The first report described work activities for 2007 and 2008; this report covers work activities conducted in 2009. Important differences between the two reports are that (1) this report does not lump all the Effectiveness Monitoring act
Authors
Zachary H. Bowen, Cameron L. Aldridge, Patrick J. Anderson, Timothy J. Assal, Laura R. H. Biewick, Steven W. Blecker, R. Sky Bristol, Natasha B. Carr, Anna D. Chalfoun, Geneva W. Chong, James E. Diffendorfer, Bradley C. Fedy, Steven L. Garman, Stephen S. Germaine, Richard I. Grauch, JoAnn M. Holloway, Collin G. Homer, Matthew Kauffman, Douglas Keinath, Natalie Latysh, Daniel J. Manier, Robert R. McDougal, Cynthia P. Melcher, Kirk A. Miller, Jessica Montag, Constance J. Nutt, Christopher J. Potter, Hall Sawyer, Spencer Schell, Sarah L. Shafer, David B. Smith, Lisa L. Stillings, Michele L. Tuttle, Anna B. Wilson