Publications
Filter Total Items: 1423
The origin and paleoclimatic significance of carbonate sand dunes deposited on the California Channel Islands during the last glacial period The origin and paleoclimatic significance of carbonate sand dunes deposited on the California Channel Islands during the last glacial period
No abstract available.
Authors
Daniel R. Muhs, Gary Skipp, R. Randall Schumann, Donald L. Johnson, John P. McGeehin, Jossh Beann, Joshua Freeman, Timothy A. Pearce, Zachary Muhs Rowland
Evaluating hydrological response to forecasted land-use change—scenario testing with the automated geospatial watershed assessment (AGWA) tool Evaluating hydrological response to forecasted land-use change—scenario testing with the automated geospatial watershed assessment (AGWA) tool
Envisioning and evaluating future scenarios has emerged as a critical component of both science and social decision-making. The ability to assess, report, map, and forecast the life support functions of ecosystems is absolutely critical to our capacity to make informed decisions to maintain the sustainable nature of our ecosystem services now and into the future. During the past two...
Authors
William G. Kepner, Darius J. Semmens, Mariano Hernandez, David C. Goodrich
Late Pleistocene paleohydrology near the boundary of the Sonoran and Chihuahuan Deserts, southeastern Arizona, USA Late Pleistocene paleohydrology near the boundary of the Sonoran and Chihuahuan Deserts, southeastern Arizona, USA
Ground-water discharge (GWD) deposits form in arid environments as water tables rise and approach or breach the ground surface during periods of enhanced effective precipitation. Where preserved, these deposits contain information on the timing and elevation of past ground-water fluctuations. Here we report on the investigation of a series of GWD deposits that are exposed in...
Authors
Jeffery S. Pigati, Jordon E. Bright, Timothy M. Shanahan, Shannon Mahan
Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin Using a coupled groundwater/surface-water model to predict climate-change impacts to lakes in the Trout Lake Watershed, northern Wisconsin
A major focus of the U.S. Geological Survey’s Trout Lake Water, Energy, and Biogeochemical Budgets (WEBB) project is the development of a watershed model to allow predictions of hydrologic response to future conditions including land-use and climate change. The coupled groundwater/surface-water model GSFLOW was chosen for this purpose because it could easily incorporate an existing...
Authors
Randall J. Hunt, John F. Walker, Steven L. Markstrom, Lauren E. Hay, John Doherty
Database of the geologic map of North America— Adapted from the map by J.C. Reed, Jr. and others (2005) Database of the geologic map of North America— Adapted from the map by J.C. Reed, Jr. and others (2005)
Introduction The Geological Society of America's (GSA) Geologic Map of North America (Reed and others, 2005a; 1:5,000,000) shows the geology of a significantly large area of the Earth, centered on North and Central America and including the submarine geology of parts of the Atlantic and Pacific Oceans. This map is now converted to a Geographic Information System (GIS) database that...
Authors
Christopher P. Garrity, David R. Soller
Effects of experimental protocol on global vegetation model accuracy: a comparison of simulated and observed vegetation patterns for Asia Effects of experimental protocol on global vegetation model accuracy: a comparison of simulated and observed vegetation patterns for Asia
Prognostic vegetation models have been widely used to study the interactions between environmental change and biological systems. This study examines the sensitivity of vegetation model simulations to: (i) the selection of input climatologies representing different time periods and their associated atmospheric CO2 concentrations, (ii) the choice of observed vegetation data for evaluating...
Authors
Guoping Tang, Sarah L. Shafer, Patrick J. Barlein, Justin O. Holman
Late Quaternary sedimentary features of Bear Lake, Utah and Idaho Late Quaternary sedimentary features of Bear Lake, Utah and Idaho
Bear Lake sediments were predominantly aragonite for most of the Holocene, reflecting a hydrologically closed lake fed by groundwater and small streams. During the late Pleistocene, the Bear River flowed into Bear Lake and the lake waters spilled back into the Bear River drainage. At that time, sediment deposition was dominated by siliciclastic sediment and calcite. Lake-level...
Authors
J. P. Smoot
The ecological and hydrological significance of ephemeral and intermittent streams in the arid and semi-arid American Southwest The ecological and hydrological significance of ephemeral and intermittent streams in the arid and semi-arid American Southwest
No abstract available.
Authors
Lainie R. Levick, David C. Goodrich, Mariano Hernandez, Julia Fonseca, Darius J. Semmens, Juliet C. Stromberg, Melanie Tluczek, R. A. Leidy, Melissa Scianni, D. Phillip Guertin, William G. Kepner
Mapping vulnerability to disasters in Latin America and the Caribbean, 1900–2007 Mapping vulnerability to disasters in Latin America and the Caribbean, 1900–2007
The vulnerability of a population and its infrastructure to disastrous events is a factor of both the probability of a hazardous event occurring and the community's ability to cope with the resulting impacts. Therefore, the ability to accurately identify vulnerable populations and places in order to prepare for future hazards is of critical importance for disaster mitigation programs...
Authors
Miriam C. Maynard-Ford, Emily C. Phillips, Peter G. Chirico
The search for Braddock’s Caldera— Guidebook for Colorado Scientific Society Fall 2008 field trip, Never Summer Mountains, Colorado The search for Braddock’s Caldera— Guidebook for Colorado Scientific Society Fall 2008 field trip, Never Summer Mountains, Colorado
The report contains the illustrated guidebook that was used for the fall field trip of the Colorado Scientific Society on September 6-7, 2008. It summarizes new information about the Tertiary geologic history of the northern Front Range and the Never Summer Mountains, particularly the late Oligocene volcanic and intrusive rocks designated the Braddock Peak complex. Minor modifications...
Authors
J. C. Cole, Ed Larson, Lang Farmer, Karl S. Kellogg
Mineralogic Causes of Variations in Magnetic Susceptibility of Late Pleistocene and Holocene Sediment from Great Salt Lake, Utah Mineralogic Causes of Variations in Magnetic Susceptibility of Late Pleistocene and Holocene Sediment from Great Salt Lake, Utah
We describe here results of magnetic susceptibility (MS) measurements and magnetic mineralogy of sediments sampled in three cores from the south basin of Great Salt Lake. The cores were obtained in 1996 with a Kullenburg-type piston corer at sites in close proximity: core 96-4 at 41 deg 01.00' N, 112 deg 28.00' W and cores 96-5 and 96-6 at 41 deg 00.09' N, 112 deg 23.05' W. Cores 96-5 (2...
Authors
Richard L. Reynolds, Joseph G. Rosenbaum, Robert S. Thompson
Stratigraphic models for deep-water sedimentary systems Stratigraphic models for deep-water sedimentary systems
Stratigraphic models predict sedimentary architecture. Prediction requires understanding systems across a sufficient range of scales. To be predictive a model must address the interaction of multiple process-response relationships. For deep-water systems these processes include (1) subaqueous flow initiation and transformation, (2) linkages between channel, levee and lobe processes, and...
Authors
Michael H. Gardner, James M. Borer, Brian W. Romans, Noelia Baptista, Erik K. Kling, Diah Hanggoro, Jesse J. Melick, Roger M. Wagerle, Marieke Dechesne, Mary M. Carr, Robert Amerman, Safian Atan