Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

10462 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 245, results 6101 - 6125

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Geology of Delaware Water Gap National Recreation Area, New Jersey-Pennsylvania
Jack B. Epstein
2006, GSA Field Guides (8) 47-63
Many of the parks within the National Park System owe their uniqueness to their geologic framework. Their scenery is the result of diverse natural processes acting upon a variety of rocks that were deposited in varied environments in the geologic past. The Delaware Water Gap National Recreation Area (DEWA) contains...
Fulfilling a paradoxical mandate: can the Environmental Water Account ensure the reliability of freshwater exports from the Sacramento-San Joaquin Delta and simultaneously protect delta smelt (Hypomesus transpacificus) from excessive entrainment?
Zach Hymanson, Larry R. Brown
2006, Interagency Ecological Program Newsletter (19) 28-49
The San Francisco Estuary (SFE) is often defined by its extremes. It is considered one of the most urbanized estuaries in the world (Conomos 1979, Nichols et al. 1986), and one of the most invaded estuaries in the United States, with hundreds of aquatic nonindigenous species established throughout the system...
Guided to gather: toy plane upgraded with telemetry
Vanessa Wiese, Dana Wiese
2006, GPS World (17) 32-38
GPS/INS and infrared optical sensors propel USGS's transformation of a remote-controlled one-quarter scale recreational aircraft into a low-cost unmanned aerial vehicle designed for environmental particulate collection....
Quiescent deformation of the Aniakchak Caldera, Alaska mapped by InSAR
Oh-Ig Kwoun, Zhong Lu, Christina A. Neal, Charles W. Wicks Jr.
2006, Geology (34) 5-8
The 10-km-wide caldera of the historically active Aniakchak volcano, Alaska, subsides ∼13 mm/yr, based on data from 19 European Remote Sensing Satellite (ERS-1 and ERS-2) interferometric synthetic aperture radar (InSAR) images from 1992 through 2002. The pattern of subsidence does not reflect the distribution of pyroclastic deposits from the last...
In situ study of mass transfer in aqueous solutions under high pressures via Raman spectroscopy: A new method for the determination of diffusion coefficients of methane in water near hydrate formation conditions
W.J. Lu, I.-M. Chou, R.C. Burruss, M.Z. Yang
2006, Applied Spectroscopy (60) 122-129
A new method was developed for in situ study of the diffusive transfer of methane in aqueous solution under high pressures near hydrate formation conditions within an optical capillary cell. Time-dependent Raman spectra of the solution at several different spots along the one-dimensional diffusion path were collected and thus the...
Lesser scaup winter foraging and nutrient reserve acquisition in east-central Florida
G. Herring, J.A. Collazo
2006, Journal of Wildlife Management (70) 1682-1689
Lesser scaup (Aythya affinis) populations have been declining since the late 1970s. One of the explanations to account for this decline, the spring-condition hypothesis (SCH), is based on the premise that scaup are limited by their ability to acquire or maintain nutrient reserves during migration to the breeding grounds, leading...
Repeatability observations from a time-lapse seismic survey
S.L. Walters, R. D. Miller, A.E. Raef
2006, SEG Technical Program Expanded Abstracts (25) 3185-3189
Time-lapse seismic surveys have proven extremely valuable in recent years, having numerous economical and environmental applications. To fully utilize this monitoring technique, problems associated with recording repeatability must be minimized. Much work has been done to equalize data from one survey to the next via processing techniques (Huang et al.,...
Kinetics of sorption and abiotic oxidation of arsenic(III) by aquifer materials
A. Amirbahman, D.B. Kent, G.P. Curtis, J.A. Davis
2006, Geochimica et Cosmochimica Acta (70) 533-547
The fate of arsenic in groundwater depends largely on its interaction with mineral surfaces. We investigated the kinetics of As(III) oxidation by aquifer materials collected from the USGS research site at Cape Cod, MA, USA, by conducting laboratory experiments. Five different solid samples with similar specific surface areas (0.6–0.9 m2 g−1) and...
Atmospheric dust in modern soil on aeolian sandstone, Colorado Plateau (USA): Variation with landscape position and contribution to potential plant nutrients
Richard L. Reynolds, J. Neff, Marith C. Reheis, Paul J. Lamothe
2006, Geoderma (130) 108-123
Rock-derived nutrients in soils originate from both local bedrock and atmospheric dust, including dust from far-distant sources. Distinction between fine particles derived from local bedrock and from dust provides better understanding of the landscape-scale distribution and abundance of soil nutrients. Sandy surficial deposits over dominantly sandstone substrates, covering vast upland...
Denitrification potential in stream sediments impacted by acid mine drainage: Effects of pH, various electron donors, and iron
J.L. Baeseman, R. L. Smith, J. Silverstein
2006, Microbial Ecology (51) 232-241
Acid mine drainage (AMD) contaminates thousands of kilometers of stream in the western United States. At the same time, nitrogen loading to many mountain watersheds is increasing because of atmospheric deposition of nitrate and increased human use. Relatively little is known about nitrogen cycling in acidic, heavy-metal-laden streams; however,...
Predicting tree species presence and basal area in Utah: A comparison of stochastic gradient boosting, generalized additive models, and tree-based methods
Gretchen G. Moisen, E.A. Freeman, J.A. Blackard, T.S. Frescino, N.E. Zimmermann, T.C. Edwards Jr.
2006, Ecological Modelling (199) 176-187
Many efforts are underway to produce broad-scale forest attribute maps by modelling forest class and structure variables collected in forest inventories as functions of satellite-based and biophysical information. Typically, variants of classification and regression trees implemented in Rulequest's?? See5 and Cubist (for binary and continuous responses, respectively) are the tools...
Estimates of in situ gas hydrate concentration from resistivity monitoring of gas hydrate bearing sediments during temperature equilibration
M. Riedel, P.E. Long, T. S. Collett
2006, Marine Geology (227) 215-225
As part of Ocean Drilling Program Leg 204 at southern Hydrate Ridge off Oregon we have monitored changes in sediment electrical resistivity during controlled gas hydrate dissociation experiments. Two cores were used, each filled with gas hydrate bearing sediments (predominantly mud/silty mud). One core was from Site 1249 (1249F-9H3), 42.1...
Demography, genetics, and the value of mixed messages
John M. Pearce, Sandra L. Talbot
2006, Condor (108) 474-479
Iverson et al. (2004) used estimates of the homing rate for molting adult Harlequin Ducks (Histrionicus histrionicus) in Alaska to draw inferences about population structure. Homing rates, defined as one minus the ratio of birds recaptured elsewhere to those recaptured at the original banding site, were high (0.95–1.00) for males...
Numerical modeling of a long-term in situ chemical osmosis experiment in the Pierre Shale, South Dakota
A.M. Garavito, H. Kooi, C. E. Neuzil
2006, Advances in Water Resources (29) 481-492
We have numerically modeled evolving fluid pressures and concentrations from a nine-year in situ osmosis experiment in the Pierre Shale, South Dakota. These data were obtained and recently interpreted by one of us (C.E.N.) as indicating a potentially significant role for chemical osmosis in media like the Pierre Shale. That...
Probabilistic analysis of tsunami hazards
E.L. Geist, T. Parsons
2006, Natural Hazards (37) 277-314
Determining the likelihood of a disaster is a key component of any comprehensive hazard assessment. This is particularly true for tsunamis, even though most tsunami hazard assessments have in the past relied on scenario or deterministic type models. We discuss probabilistic tsunami hazard analysis (PTHA) from the standpoint of integrating...
Late Cretaceous base level lowering in Campanian and Maastrichtian depositional sequences, Kure Beach, North Carolina
W.B. Harris, Self-Trail J.M.
2006, Stratigraphy (3) 195-216
Campanian through Maastrichtian mixed carbonate and siliciclastic sediments in a 422 m continuous core drilled at Kure Beach, NC provide a record of sea-level change. Based on lithology and stratigraphy, depositional sequences are defined, and calcareous nannofossil zones and 87Sr/86Sr ratios and corresponding ages using the LOWESS Table determined. Campanian...
Slip on the San Andreas fault at Parkfield, California, over two earthquake cycles, and the implications for seismic hazard
J. Murray, J. Langbein
2006, Bulletin of the Seismological Society of America (96)
Parkfield, California, which experienced M 6.0 earthquakes in 1934, 1966, and 2004, is one of the few locales for which geodetic observations span multiple earthquake cycles. We undertake a comprehensive study of deformation over the most recent earthquake cycle and explore the results in the context of geodetic data collected...
Striping artifact reduction in lunar orbiter mosaic images
P.A. Mlsna, T. Becker
2006, Conference Paper, Proceedings of the IEEE Southwest Symposium on Image Analysis and Interpretation
Photographic images of the moon from the 1960s Lunar Orbiter missions are being processed into maps for visual use. The analog nature of the images has produced numerous artifacts, the chief of which causes a vertical striping pattern in mosaic images formed from a series of filmstrips. Previous methods of...
Submarine gravity slides on the Paleozoic continental slope at the western edge of the Great Basin, east-cental California: A mechanism for development of unconformities in slope environments
C.H. Stevens, P. Stone
2006, Stratigraphy (3) 139-149
The middle Paleozoic continental slope, represented by rocks exposed near Badger Flat in the northwestern Inyo Mountains, at the western edge of the Great Basin in east-central California, failed by submarine gravity sliding twice during Silurian and Devonian time. Each time a major unconformity was developed between the surface exposed...
Emplacement of the Kodiak batholith and slab-window migration
David W. Farris, Peter J. Haeussler, Richard Friedman, Scott R. Paterson, R. W. Saltus, Robert A. Ayuso
2006, Geological Society of America Bulletin (118) 1360-1376
The Kodiak batholith is one of the largest, most elongate intrusive bodies in the forearc Sanak-Baranof plutonic belt located in southern Alaska. This belt is interpreted to have formed during the subduction of an oceanic spreading center and the associated migration of a slab window. Individual plutons of the Kodiak...
Photometric properties of Titan's surface from Cassini VIMS: Relevance to titan's hemispherical albedo dichotomy and surface stability
R.M. Nelson, R. H. Brown, B.W. Hapke, W. D. Smythe, L. Kamp, M.D. Boryta, F. Leader, K. H. Baines, G. Bellucci, J.-P. Bibring, B. J. Buratti, F. Capaccioni, P. Cerroni, R. N. Clark, M. Combes, A. Coradini, D. P. Cruikshank, P. Drossart, V. Formisano, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, P. D. Nicholson, B. Sicardy, Christophe Sotin
2006, Planetary and Space Science (54) 1540-1551
The Visual and Infrared Mapping Spectrometer (VIMS) instrument on the Cassini Saturn Orbiter returned spectral imaging data as the spacecraft undertook six close encounters with Titan beginning 7 July, 2004. Three of these flybys each produced overlapping coverage of two distinct regions of Titan's surface. Twenty-four points were selected on...
Titan: Preliminary results on surface properties and photometry from VIMS observations of the early flybys
B. J. Buratti, Christophe Sotin, R. H. Brown, M.D. Hicks, R. N. Clark, J. A. Mosher, T. B. McCord, R. Jaumann, K. H. Baines, P. D. Nicholson, T. Momary, D.P. Simonelli, B. Sicardy
2006, Planetary and Space Science (54) 1498-1509
Cassini observations of the surface of Titan offer unprecedented views of its surface through atmospheric windows in the 1-5 ??m region. Images obtained in windows for which the haze opacity is low can be used to derive quantitative photometric parameters such as albedo and albedo distribution, and physical properties such...
Negative magnetic anomaly over Mt. Resnik, a subaerially erupted volcanic peak beneath the West Antarctic Ice Sheet
John C. Behrendt, Carol A. Finn, D. L. Morse, D. D. Blankenship
2006, Terra Antarctica (12) 203-212
Mt. Resnik is one of the previously reported 18 subaerially erupted volcanoes (in the West Antarctic rift system), which have high elevation and high bed relief beneath the WAIS in the Central West Antarctica (CWA) aerogeophysical survey. Mt. Resnik lies 300 m below the surface of the West Antarctic Ice...
Mobilization of lead and other trace elements following shock chlorination of wells
R. L. Seiler
2006, Science of the Total Environment (367) 757-768
Many owners of domestic wells shock chlorinate their wells to treat for bacterial contamination or control bad odors from sulfides. Analysis of well water with four wells from Fallon, Nevada, showed that following recommended procedures for shock chlorinating wells can cause large, short-lasting increases in trace-element concentrations in ground water,...
Light-mediated Zn uptake in photosynthetic biofilm
J.M. Morris, A.M. Farag, D. A. Nimick, J.S. Meyer
2006, Hydrobiologia (571) 361-371
Our experiments conducted under controlled laboratory conditions demonstrate diel uptake and release of zinc (Zn) in lab-cultured biofilm exposed to Zn concentrations that are present in some mining-impacted streams (1–2 mg Zn/l). Specifically, at constant pH, temperature, and aqueous Zn concentrations in the exposure water, biofilm accumulated Zn during the light...