Publications
Filter Total Items: 1493
Identifying buried segments of active faults in the northern Rio Grande Rift using aeromagnetic, LiDAR,and gravity data, south-central Colorado, USA Identifying buried segments of active faults in the northern Rio Grande Rift using aeromagnetic, LiDAR,and gravity data, south-central Colorado, USA
Combined interpretation of aeromagnetic and LiDAR data builds on the strength of the aeromagnetic method to locate normal faults with significant offset under cover and the strength of LiDAR interpretation to identify the age and sense of motion of faults. Each data set helps resolve ambiguities in interpreting the other. In addition, gravity data can be used to infer the sense of motion...
Authors
V. J. S. Grauch, Chester A. Ruleman
Mapping, monitoring, and modeling Western Gateway Community landscape dynamics Mapping, monitoring, and modeling Western Gateway Community landscape dynamics
Federal public lands in the western United States are becoming increasingly surrounded by Gateway Communities. These communities are undergoing landscape change due to population growth, economic growth, and the resulting land-use development. Socioeconomic, demographic, and land-use changes in Gateway Communities are often perceived as threats to Federal land resources, natural...
Authors
D. J. Hester
Quaternary geologic map of the Shelby 1° x 2° quadrangle, Montana Quaternary geologic map of the Shelby 1° x 2° quadrangle, Montana
The Shelby quadrangle encompasses approximately 16,084 km2 (6,210 mi2). The northern boundary is the Montana/Saskatchewan (U.S./Canada) boundary. The quadrangle is in the Northern Plains physiographic province and it includes the Sweet Grass Hills. The primary river is the Marias River. The ancestral Missouri River was diverted south of the Bearpaw Mountains by a Laurentide ice sheet...
Authors
David S. Fullerton, Roger B. Colton, Charles A. Bush
A framework for quantitative assessment of impacts related to energy and mineral resource development A framework for quantitative assessment of impacts related to energy and mineral resource development
Natural resource planning at all scales demands methods for assessing the impacts of resource development and use, and in particular it requires standardized methods that yield robust and unbiased results. Building from existing probabilistic methods for assessing the volumes of energy and mineral resources, we provide an algorithm for consistent, reproducible, quantitative assessment of...
Authors
Seth S. Haines, James Diffendorfer, Laurie S. Balistrieri, Byron R. Berger, Troy A. Cook, Donald L. Gautier, Tanya J. Gallegos, Margot Gerritsen, Elisabeth Graffy, Sarah Hawkins, Kathleen Johnson, Jordan Macknick, Peter McMahon, Tim Modde, Brenda Pierce, John H. Schuenemeyer, Darius J. Semmens, Benjamin Simon, Jason Taylor, Katherine Walton-Day
An automated digital imaging system for environmental monitoring applications An automated digital imaging system for environmental monitoring applications
Recent improvements in the affordability and availability of high-resolution digital cameras, data loggers, embedded computers, and radio/cellular modems have advanced the development of sophisticated automated systems for remote imaging. Researchers have successfully placed and operated automated digital cameras in remote locations and in extremes of temperature and humidity, ranging...
Authors
Rian Bogle, Miguel Velasco, John Vogel
234U/238U and δ87Sr in peat as tracers of paleosalinity in the Sacramento-San Joaquin Delta of California, USA 234U/238U and δ87Sr in peat as tracers of paleosalinity in the Sacramento-San Joaquin Delta of California, USA
The purpose of this study was to determine the history of paleosalinity over the past 6000+ years in the Sacramento-San Joaquin Delta (the Delta), which is the innermost part of the San Francisco Estuary. We used a combination of Sr and U concentrations, d87Sr values, and 234U/238U activity ratios (AR) in peat as proxies for tracking paleosalinity. Peat cores were collected in marshes on...
Authors
Judith Z. Drexler, James B. Paces, Charles N. Alpers, Lisamarie Windham-Myers, Leonid A. Neymark, Thomas D. Bullen, Howard E. Taylor
Loess and its geomorphic, stratigraphic and paleoclimatic significance in the Quaternary Loess and its geomorphic, stratigraphic and paleoclimatic significance in the Quaternary
Loess is aeolian silt visible in the field as a sedimentary body. It covers a significant portion of the land surface of the Earth. Loess thickness, particle size, and carbonate content decrease downwind from sources, useful trends for paleowinds. Many loess sections consist of relatively thick deposits of mostly unaltered sediment with intercalated paleosols. Paleosols represent periods...
Authors
Daniel R. Muhs
Laramide basin CSI: Comprehensive stratigraphic investigations of Paleogene sediments in the Colorado Headwaters Basin, north-central Colorado Laramide basin CSI: Comprehensive stratigraphic investigations of Paleogene sediments in the Colorado Headwaters Basin, north-central Colorado
The Paleogene sedimentary deposits of the Colorado Headwaters Basin provide a detailed proxy record of regional deformation and basin subsidence during the Laramide orogeny in north-central Colorado and southern Wyoming. This field trip presents extensive evidence from sedimentology, stratigraphy, structure, palynology, and isotope geochronology that shows a complex history that is...
Authors
Marieke Dechesne, James C. Cole, James H. Trexler, Patricia Cashman, Christopher D Peterson
Accumulation of organic carbon-rich strata along the western margin and in the center of the North American western interior seaway during the Cenomanian-Turonian Transgression: Chapter 3 Accumulation of organic carbon-rich strata along the western margin and in the center of the North American western interior seaway during the Cenomanian-Turonian Transgression: Chapter 3
No abstract available.
Authors
W.E. Dean, E.G. Kauffman, M.A. Arthur
Deformational and erosional history for the Abiquiu and contiguous area, north-central New Mexico: Implications for formation of the Abiquiu embayment and a discussion of new geochronological and geochemical analysis Deformational and erosional history for the Abiquiu and contiguous area, north-central New Mexico: Implications for formation of the Abiquiu embayment and a discussion of new geochronological and geochemical analysis
Geologic mapping, age determinations, and geochemistry of rocks exposed in the Abiquiu area of the Abiquiu embayment of the Rio Grande rift, north-central New Mexico, provide data to determine fault-slip and incision rates. Vertical-slip rates for faults in the area range from 16 m/m.y. to 42 m/m.y., and generally appear to decrease from the eastern edge of the Colorado Plateau to the...
Authors
Florian Maldonado, Daniel P. Miggins, James R. Budahm
Ion-probe U–Pb dating of authigenic and detrital opal from Neogene-Quaternary alluvium Ion-probe U–Pb dating of authigenic and detrital opal from Neogene-Quaternary alluvium
Knowing depositional ages of alluvial fans is essential for many tectonic, paleoclimatic, and geomorphic studies in arid environments. The use of U–Pb dating on secondary silica to establish the age of Neogene-Quaternary clastic sediments was tested on samples of authigenic and detrital opal and chalcedony from depths of ∼25 to 53 m in boreholes at Midway Valley, Nevada. Dating of...
Authors
Leonid A. Neymark, James B. Paces
Towards a publicly available, map-based regional software tool to estimate unregulated daily streamflow at ungauged rivers Towards a publicly available, map-based regional software tool to estimate unregulated daily streamflow at ungauged rivers
Streamflow information is critical for addressing any number of hydrologic problems. Often, streamflow information is needed at locations that are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate...
Authors
Stacey A. Archfield, Peter A. Steeves, John D. Guthrie, Kernell G. Ries