Conference Papers
Science Quality and Integrity
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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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A preliminary evaluation of Trinity river sediment and nutrient loads into Galveston Bay, Texas, during two periods of high flow
Suspend-sediment and water-quality data were measured during two periods of high flow, one during April 20-23, 2009 and a second during September 22-November 3, 2009. On the basis of streamflow and continuous and discrete water-quality measurements, the two periods of high flow had different flood and nutrient loading characteristics. Some differences in the nature of these two periods of high flo
Authors
Michael T. Lee
An automated and universal method for measuring mean grain size from a digital image of sediment
Existing methods for estimating mean grain size of sediment in an image require either complicated sequences of image processing (filtering, edge detection, segmentation, etc.) or statistical procedures involving calibration. We present a new approach which uses Fourier methods to calculate grain size directly from the image without requiring calibration. Based on analysis of over 450 images, we f
Authors
Daniel D. Buscombe, David M. Rubin, Jonathan A. Warrick
Analyzing turbidity, suspended-sediment concentration, and particle-size distribution resulting from a debris flow on Mount Jefferson, Oregon, November 2006
A debris flow and sediment torrent occurred on the flanks of Mt Jefferson in Oregon on November 6, 2006, inundating 150 acres of forest. The massive debris flow was triggered by a rock and snow avalanche from the Milk Creek glaciers and snowfields during the early onset of an intense storm originating near the Hawaiian Islands. The debris flow consisted of a heavy conglomerate of large boulders, c
Authors
Mark A. Uhrich
Evaluating the effect of Tikhonov regularization schemes on predictions in a variable-density groundwater model
Calibration of highly‐parameterized numerical models typically requires explicit Tikhonovtype regularization to stabilize the inversion process. This regularization can take the form of a preferred parameter values scheme or preferred relations between parameters, such as the preferred equality scheme. The resulting parameter distributions calibrate the model to a user‐defined acceptable level of
Authors
Jeremy T. White, Christian D. Langevin, Joseph D. Hughes
Use of time series and harmonic constituents of tidal propagation to enhance estimation of coastal aquifer heterogeneity
A synthetic two‐dimensional model of a horizontally and vertically heterogeneous confined coastal aquifer system, based on the Upper Floridan aquifer in south Florida, USA, subjected to constant recharge and a complex tidal signal was used to generate 15‐minute water‐level data at select locations over a 7‐day simulation period. “Observed” water‐level data were generated by adding noise, represe
Authors
Joseph D. Hughes, Jeremy T. White, Christian D. Langevin
Assessing societal vulnerability of U.S. Pacific Northwest communities to storm-induced coastal change
Progressive increases in storm intensities and extreme wave heights have been documented along the U.S. West Coast. Paired with global sea level rise and the potential for an increase in El Niño occurrences, these trends have substantial implications for the vulnerability of coastal communities to natural coastal hazards. Community vulnerability to hazards is characterized by the exposure, sensit
Authors
Heather M. Baron, Nathan J. Wood, Peter Ruggerio, Jonathan Allan, Patrick Corcoran
Climate change, cranes, and temperate floodplain ecosystems
Floodplain ecosystems provide important habitat to cranes globally. Lateral, longitudinal, vertical, and temporal hydrologic connectivity in rivers is essential to maintaining the functions and values of these systems. Agricultural development, flood control, water diversions, dams, and other anthropogenic activities have greatly affected hydrologic connectivity of river systems worldwide and alte
Authors
Sammy L. King
A geochemical module for "AMDTreat" to compute caustic quantity, effluent quantity, and sludge volume
Treatment with caustic chemicals typically is used to increase pH and decrease concentrations of dissolved aluminum, iron, and/or manganese in largevolume, metal-laden discharges from active coal mines. Generally, aluminum and iron can be removed effectively at near-neutral pH (6 to 8), whereas active manganese removal requires treatment to alkaline pH (~10). The treatment cost depends on the spec
Authors
Charles A. Cravotta, David L. Parkhurst, Brent P Means, Bob McKenzie, Harry Morris, Bill Arthur
Modeling the dynamic geochemistry of prairie pothole wetlands
No abstract available.
Authors
M.C. Goldhaber, C.T. Mills, Craig A. Stricker, J. W. LaBaugh, D. Mushet, N.H. Euliss
Comparison of turbidity to multi-frequency sideways-looking acoustic-Doppler data and suspended-sediment data in the Colorado River in Grand Canyon
Water clarity is important to biologists when studying fish and other fluvial fauna and flora. Turbidity is an indicator of the cloudiness of water, or reduced water clarity, and is commonly measured using nephelometric sensors that record the scattering and absorption of light by particles in the water. Unfortunately, nephelometric sensors only operate over a narrow range of the conditions typica
Authors
Nicholas Voichick, David J. Topping
The upper crust on its side---Steeply tilted slabs in the basin and range
No abstract available.
Authors
Keith A. Howard
Evaluation of the role of magmatic volatiles from Eocene mafic to felsic igneous rocks in the formation of Carlin-type gold deposits of the Carlin trend and Jerritt Canyon District as constrained by preliminary He, Pb, Sr, and Nd isotopic data
No abstract available.
Authors
Albert H. Hofstra, Gary P. Landis, Wayne R. Premo, M.W. Ressel, Christopher D. Henry