Conference Papers
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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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The use of synthetic jarosite as an analog for natural jarosite The use of synthetic jarosite as an analog for natural jarosite
The presence of jarosite in soil or mining waste is an indicator of acidic sulfate-rich conditions. Physical and chemical properties of synthetic jarosites are commonly used as analogs in laboratory studies to determine solubility and acid-generation of naturally occurring jarosites. In our work we have mineralogically and chemically characterized both natural and synthetic jarosites...
Authors
George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Rhonda L. Driscoll, Reinhard W. Leinz
The utility of gravity and magnetic methods for understanding subsurface hydrogeology in large alluvial watersheds: Examples from urbanized basins of the Western United States The utility of gravity and magnetic methods for understanding subsurface hydrogeology in large alluvial watersheds: Examples from urbanized basins of the Western United States
Population continues to grow rapidly within the large alluvial watersheds associated with structural basins of the Basin and Range Province and the Rio Grande rift of the western United States. Increasing demands on ground‐water resources in these basins, combined with water‐rights disputes, have amplified the need for improved understanding of subsurface hydrogeology. Gravity and...
Authors
V. J. S. Grauch, Victoria Langenheim
Towards sustainable management of Louisiana's coastal wetland forests: Problems, constraints, and a new beginning Towards sustainable management of Louisiana's coastal wetland forests: Problems, constraints, and a new beginning
Over 345,000 ha of forested swamps occur throughout the Mississippi River Deltaic Plain. Natural and anthropogenic changes in hydrology and geomorphology at local and landscape levels have reduced the productivity in many of these coastal wetland forests areas and have caused the complete loss of forest cover in some places. A summary and interpretation of the available science...
Authors
J. L. Chambers, W.H. Conner, R.F. Keim, S.P. Faulkner, J.W. Day, E.S. Gardiner, M.S. Hughes, S.L. King, K.W. McLeod, C.A. Miller, J.A. Nyman, G.P. Shaffer
Trends in the nutrient enrichment of U.S. rivers during the late 20th century and their relation to changes in probable stream trophic conditions Trends in the nutrient enrichment of U.S. rivers during the late 20th century and their relation to changes in probable stream trophic conditions
We estimated trends in concentrations of total phosphorus (TP) and total nitrogen (TN) and the related change in the probabilities of trophic conditions from 1975 to 1994 at 250 nationally representative riverine monitoring locations in the U.S. with drainage areas larger than about 1,000 km2. Statistically significant (p 0.05) declines were detected in TP and TN concentrations at 44%...
Authors
R. B. Alexander, R. A. Smith
Uranium-series constraints on subrepository water flow at yucca mountain, nevada Uranium-series constraints on subrepository water flow at yucca mountain, nevada
Mineral abundances and whole-rock chemical and uranium-series isotopic compositions were measured in unfractured and rubble core samples from borehole USW SD-9 in the same layers of variably zeolitized tuffs that underlie the proposed nuclear waste repository at Yucca Mountain, Nevada. Uranium concentrations and isotopic compositions also were measured in pore water from core samples...
Authors
L.A. Neymark, S.J. Chipera, J.B. Paces, D. T. Vaniman
Use of the moon to support on-orbit sensor calibration for climate change measurements Use of the moon to support on-orbit sensor calibration for climate change measurements
Production of reliable climate datasets from multiple observational measurements acquired by remote sensing satellite systems available now and in the future places stringent requirements on the stability of sensors and consistency among the instruments and platforms. Detecting trends in environmental parameters measured at solar reflectance wavelengths (0.3 to 2.5 microns) requires on...
Authors
T.C. Stone, H. H. Kieffer
Use of thermodynamic sorption models to derive radionuclide Kd values for performance assessment: Selected results and recommendations of the NEA sorption project Use of thermodynamic sorption models to derive radionuclide Kd values for performance assessment: Selected results and recommendations of the NEA sorption project
For the safe final disposal and/or long-term storage of radioactive wastes, deep or near-surface underground repositories are being considered world-wide. A central safety feature is the prevention, or sufficient retardation, of radionuclide (RN) migration to the biosphere. To this end, radionuclide sorption is one of the most important processes. Decreasing the uncertainty in...
Authors
M. Ochs, J.A. Davis, M. Olin, T.E. Payne, C.J. Tweed, M.M. Askarieh, S. Altmann
USGS directions in MODFLOW development USGS directions in MODFLOW development
[No abstract available]
Authors
P. M. Barlow, A.W. Harbaugh
USGS Magellan stereomapping of Venus USGS Magellan stereomapping of Venus
This paper describes our methods for generating high resolution Digital Terrain Models (DTMs) of Venus using Magellan synthetic aperture radar (SAR) stereoimages, and the sensor model we developed for Magellan stereomapping on our digital photogrammetric workstation running SOCET SET (® BAE SYSTEMS). In addition to demonstrating the validity of our sensor model and procedures we use for...
Authors
Elpitha Howington-Kraus, Randolph L. Kirk, Donna M. Galuszka, Bonnie L. Redding
Using models to manage systems subject to sustainability indicators Using models to manage systems subject to sustainability indicators
Mathematical and numerical models can provide insight into sustainability indicators using relevant simulated quantities, which are referred to here as predictions. To be useful, many concerns need to be considered. Four are discussed here: (a) mathematical and numerical accuracy of the model; (b) the accuracy of the data used in model development, (c) the information observations...
Authors
M. C. Hill
Using self-organizing maps to determine observation threshold limit predictions in highly variant data Using self-organizing maps to determine observation threshold limit predictions in highly variant data
A significant data quality challenge for highly variant systems surrounds the limited ability to quantify operationally reasonable limits on the data elements being collected and provide reasonable threshold predictions. In many instances, the number of influences that drive a resulting value or operational range is too large to enable physical sampling for each influencer, or is too...
Authors
C.A. Paganoni, K.C. Chang, M. B. Robblee
Varieties of submarine failure morphologies of seismically-induced landslides in Alaskan fjords Varieties of submarine failure morphologies of seismically-induced landslides in Alaskan fjords
The Great Alaska Earthquake of 1964 caused major damage and 43 deaths in the coastal communities of Seward and Valdez. Most of these losses were caused by tsunamis that occurred immediately after the earthquake and were most likely induced by local submarine landslides. Recent NOAA multibcam bathymetric surveys near Seward and Valdez provide detailed information about the morphology of...
Authors
H. Lee, H. Ryan, R. E. Kayen, Peter J. Haeussler, P. Dartnell, M. A. Hampton