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Not all publications have extents, not all extents are completely accurate
Ground-penetrating radar: A tool for monitoring bridge scour
N.L. Anderson, A.M. Ismael, T. Thitimakorn
2007, Environmental & Engineering Geoscience (13) 1-10
Ground-penetrating radar (GPR) data were acquired across shallow streams and/or drainage ditches at 10 bridge sites in Missouri by maneuvering the antennae across the surface of the water and riverbank from the bridge deck, manually or by boat. The acquired two-dimensional and three-dimensional data sets accurately image the channel bottom,...
The rate and pattern of bed incision and bank adjustment on the Colorado River in Glen Canyon downstream from Glen Canyon Dam, 1956-2000
P.E. Grams, J. C. Schmidt, D.J. Topping
2007, Geological Society of America Bulletin (119) 556-575
Closure of Glen Canyon Dam in 1963 transformed the Colorado River by reducing the magnitude and duration of spring floods, increasing the magnitude of base flows, and trapping fine sediment delivered from the upper watershed. These changes caused the channel downstream in Glen Canyon to incise, armor, and narrow. This...
Impacts of the 2004 Indian ocean tsunami on the southwest coasts of Sri Lanka
Robert A. Morton, John A. Goff, Scott L. Nichol
2007, Conference Paper, Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
The 2004 Indian Ocean tsunami caused major landscape changes along the southwest coasts of Sri Lanka that were controlled by the flow, natural topography and bathymetry, and anthropogenic modifications of the terrain. Landscape changes included substantial beach erosion and scouring of return-flow channels near the beach, and deposition of sand...
Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site
Laurence A. Soderblom, Randolph L. Kirk, Jonathan I. Lunine, Jeffrey A. Anderson, Kevin H. Baines, Jason W. Barnes, Janet M. Barrett, Robert H. Brown, Bonnie J. Buratti, Roger N. Clark, Dale P. Cruikshank, Charles Elachi, Michael A. Janssen, Ralf Jaumann, Erich Karkoschka, Stéphane Le Mouélic, Rosaly Lopes, Ralph D. Lorenz, Thomas B. McCord, Philip D. Nicholson, Jani Radebaugh, Bashar Rizk, Christophe Sotin, Ellen R. Stofan, Tracie L. Sucharski, Martin G. Tomasko, Stephen D. Wall
2007, Planetary and Space Science (55) 2025-2036
Titan's vast equatorial fields of RADAR-dark longitudinal dunes seen in Cassini RADAR synthetic aperture images correlate with one of two dark surface units discriminated as “brown” and “blue” in Visible and Infrared Mapping Spectrometer (VIMS) color composites of short-wavelength infrared spectral cubes (RGB as 2.0, 1.6, 1.3 μm). In such composites...
Recovery of three arctic stream reaches from experimental nutrient enrichment
J.P. Benstead, A.C. Green, Linda A. Deegan, B. J. Peterson, K. Slavik, W.B. Bowden, A.E. Hershey
2007, Freshwater Biology (52) 1077-1089
1. Nutrient enrichment and resulting eutrophication is a widespread anthropogenic influence on freshwater ecosystems, but recovery from nutrient enrichment is poorly understood, especially in stream environments. We examined multi-year patterns in community recovery from experimental low-concentration nutrient enrichment (N + P or P only) in three reaches of two Arctic...
Evaluation of abutment scour prediction equations with field data
S.T. Benedict, N. Deshpande, N.M. Aziz
2007, Transportation Research Record 118-126
The U.S. Geological Survey, in cooperation with FHWA, compared predicted abutment scour depths, computed with selected predictive equations, with field observations collected at 144 bridges in South Carolina and at eight bridges from the National Bridge Scour Database. Predictive equations published in the 4th edition of Evaluating Scour at Bridges...
Large-scale scour of the sea floor and the effect of natural armouring processes, land reclamation Maasvlakte 2, port of Rotterdam
S. Boer, E. Elias, S. Aarninkhof, D. Roelvink, T. Vellinga
2007, Conference Paper, Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
Morphological model computations based on uniform (non-graded) sediment revealed an unrealistically strong scour of the sea floor in the immediate vicinity to the west of Maasvlakte 2. By means of a state-of-the-art graded sediment transport model the effect of natural armouring and sorting of bed material on the scour process...
Land area changes in coastal Louisiana after Hurricanes Katrina and Rita
John A. Barras
2007, Circular 1306-5B
Comparison of classified Landsat Thematic Mapper (TM) satellite imagery acquired before and after the landfalls of Hurricanes Katrina (August 29, 2005) and Rita (September 24, 2005) demonstrated that water area increased by 217 mi2 (562 km2) in coastal Louisiana. Approximately 82 mi2 (212 km2) of new water areas were in...
Aerial rapid assessment of hurricane damages to northern Gulf coastal habitats
Thomas C. Michot, Christopher J. Wells, Paul C. Chadwick
2007, Circular 1306-5A
Hurricane Katrina made landfall in southeast Louisiana on August 29, 2005, and Hurricane Rita made landfall in southwest Louisiana on September 24, 2005. Scientists from the U.S. Geological Survey (USGS) flew aerial surveys to assess damages to natural resources and to lands owned and managed by the U.S. Department of...
Exploring rippled scour depressions offshore Huntington Beach, CA
Eleyne L. Phillips, Curt D. Storlazzi, Peter Dartnell, Brian D. Edwards
2007, Conference Paper, Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
Morphological model computations based on uniform (non-graded) sediment revealed an unrealistically strong scour of the sea floor in the immediate vicinity to the west of Maasvlakte 2. By means of a state-of-the-art graded sediment transport model the effect of natural armouring and sorting of bed material on...
Topography and geomorphology of the Huygens landing site on Titan
Laurence A. Soderblom, Martin G. Tomasko, Brent A. Archinal, Tammy L. Becker, Michael W. Bushroe, Debbie Cook, Lyn R. Doose, Donna M. Galuszka, Trent M. Hare, Elpitha Howington-Kraus, Erich Karkoschka, Randolph L. Kirk, Jonathan I. Lunine, Elisabeth A. McFarlane, Bonnie L. Redding, Bashar Rizk, Mark R. Rosiek, Charles See, Peter H. Smith
2007, Planetary and Space Science (55) 2015-2024
The Descent Imager/Spectral Radiometer (DISR) aboard the Huygens Probe took several hundred visible-light images with its three cameras on approach to the surface of Titan. Several sets of stereo image pairs were collected during the descent. The digital terrain models constructed from those images show rugged topography, in places approaching...
Distribution and abundance of California giant salamander (Dicamptodon ensatus) and signal crayfish (Pacifastacus leniusculus) in the Upper Redwood Creek Watershed, Marin County, California
Darren Fong, Judd A. Howell
2006, Open-File Report 2006-1066
A survey was conducted in 1997-1998 to identify the distribution of non-native signal crayfish (Pacifastacus leniusculus) and larval California giant salamanders (Dicamptodon ensatus) within the upper Redwood Creek watershed (Marin County, California). The crayfish is widely distributed along the mainstem Redwood Creek. It was found in lower Fern Creek but...
Seafloor character and sedimentary processes in eastern Long Island Sound and western Block Island Sound
Lawrence J. Poppe, M. L. Cohen-DiGiacomo, S. M. Smith, H.F. Stewart, N.A. Forfinski
2006, Geo-Marine Letters (26) 59-68
Multibeam bathymetric data and seismic-reflection profiles collected in eastern Long Island Sound and western Block Island Sound reveal previously unrecognized glacial features and modern bedforms. Glacial features include an ice-sculptured bedrock surface, a newly identified recessional moraine, exposed glaciolacustrine sediments, and remnants of stagnant-ice-contact deposits. Modern bedforms include fields of...
Post-Wildfire Sedimentation in Saguaro National Park, Rincon Mountain District, and Effects on Lowland Leopard Frog Habitat
John T.C. Parker
2006, Scientific Investigations Report 2006-5235
The Rincon Mountain District of Saguaro National Park occupies about 272 square kilometers of mountains, canyons, and alluvial fans in southeastern Arizona just east of Tucson. The park contains some of the last remaining habitat in the Tucson Basin of the lowland leopard frog that lives in the bedrock pools...
Geology, Water, and Wind in the Lower Helmand Basin, Southern Afghanistan
John W. Whitney
2006, Scientific Investigations Report 2006-5182
This report presents an overview of the geology, hydrology, and climate of the lower Helmand Basin, a large, closed, arid basin in southern Afghanistan. The basin is drained by the Helmand River, the only perennial desert stream between the Indus and Tigris-Euphrates Rivers. The Helmand River is the lifeblood of...
Water-level decline in the Apalachicola River, Florida, from 1954 to 2004, and effects on floodplain habitats
Helen M. Light, Kirk R. Vincent, Melanie R. Darst, Franklin D. Price
2006, Scientific Investigations Report 2006-5173
From 1954 to 2004, water levels declined in the nontidal reach of the Apalachicola River, Florida, as a result of long-term changes in stage-discharge relations. Channel widening and deepening, which occurred throughout much of the river, apparently caused the declines. The period of most rapid channel enlargement began in 1954...
1976 Big Thompson flood, Colorado — Thirty years later
Robert D. Jarrett, John E. Costa
2006, Fact Sheet 2006-3095
In the early evening of Saturday, July 31, 1976, a large stationary thunderstorm released as much as 7.5 inches of rainfall in about an hour (about 12 inches in a few hours) in the middle reaches of the Big Thompson River Basin and to a lesser extent in parts of...
1976 Big Thompson flood, Colorado
R. D. Jarrett (compiler), S.J. Vandas
2006, General Information Product 35
In the early evening of July 31, 1976, a large stationary thunderstorm released as much as 7.5 inches of rainfall in about an hour (about 12 inches in a few hours) in the upper reaches of the Big Thompson River drainage. This large amount of rainfall in such a short...
Trends of Abutment-Scour Prediction Equations Applied to 144 Field Sites in South Carolina
Stephen T. Benedict, Nikhil Deshpande, Nadim M. Aziz, Paul Conrads
2006, Open-File Report 2003-295
The U.S. Geological Survey conducted a study in cooperation with the Federal Highway Administration in which predicted abutment-scour depths computed with selected predictive equations were compared with field measurements of abutment-scour depth made at 144 bridges in South Carolina. The assessment used five equations published in the Fourth Edition of...
Geomorphic characteristics and classification of Duluth-area streams, Minnesota
Faith A. Fitzpatrick, Marie C. Peppler, Michele M. DePhilip, Kathy Lee
2006, Scientific Investigations Report 2006-5029
In 2003 and 2004, a geomorphic assessment of streams in 20 watersheds in the Duluth, Minn., area was conducted to identify and summarize geomorphic characteristics, processes, disturbance mechanisms, and potential responses to disturbance. Methods used to assess the streams included watershed characterization, descriptions of segment slopes and valley types, historical...
Hydraulic and geomorphic monitoring of experimental bridge scour mitigation at selected bridges in Utah, 2003-05
Terry A. Kenney, Tim S. McKinney
2006, Scientific Investigations Report 2006-5033
Unique bridge scour mitigation designs using concrete A-Jacks were developed by the Utah Department of Transportation and installed at the Colorado River Bridge at State Road 191 and the Green River Bridge at State Road 19. The U.S. Geological Survey monitored stream reaches at these sites by collecting streambed-topography and...
Erosion of steepland valleys by debris flows
J. D. Stock, W. E. Dietrich
2006, Geological Society of America Bulletin (118) 1125-1148
Episodic debris flows scour the rock beds of many steepland valleys. Along recent debris-flow runout paths in the western United States, we have observed evidence for bedrock lowering, primarily by the impact of large particles entrained in debris flows. This evidence may persist to the point at which debris-flow deposition...
Regional-scale assessment of a sequence-bounding paleosol on fluvial fans using ground-penetrating radar, eastern San Joaquin Valley, California
V.G.L. Bennett, G.S. Weissmann, G.S. Baker, D.W. Hyndman
2006, Geological Society of America Bulletin (118) 724-732
Recently developed sequence stratigraphic models for fluvial fans suggest that sequence boundaries in these deposits are marked by laterally extensive paleosols; however, these models were based on paleosol correlations inferred between wells. To test this, we collected ???190 km of ground-penetrating radar (GPR) profiles on three fluvial fans from the...