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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Levelling and merging of two discrete national-scale geochemical databases: A case study showing the surficial expression of metalliferous black shales
Government-sponsored, national-scale, soil and sediment geochemical databases are used to estimate regional and local background concentrations for environmental issues, identify possible anthropogenic contamination, estimate mineral endowment, explore for new mineral deposits, evaluate nutrient levels for agriculture, and establish concentration relationships with human or animal health. Because
Authors
Steven M. Smith, Ryan T. Neilson, Stuart A. Giles
Modifications to risk-targeted seismic design maps for subduction and near-fault hazards
ASCE 7-10 introduced new seismic design maps that define risk-targeted ground motions such that buildings designed according to these maps will have 1% chance of collapse in 50 years. These maps were developed by iterative risk calculation, wherein a generic building collapse fragility curve is convolved with the U.S. Geological Survey hazard curve until target risk criteria are met. Recent resear
Authors
Abbie B. Liel, Nicolas Luco, Meera Raghunandan, C. Champion
Optimization techniques using MODFLOW-GWM
An important application of optimization codes such as MODFLOW-GWM is to maximize water supply from unconfined aquifers subject to constraints involving surface-water depletion and drawdown. In optimizing pumping for a fish hatchery in a bedrock aquifer system overlain by glacial deposits in eastern Wisconsin, various features of the GWM-2000 code were used to overcome difficulties associated with
Authors
Anna Grava, Daniel T. Feinstein, Paul M. Barlow, Tullia Bonomi, Fabiola Buarne, Charles Dunning, Randall J. Hunt
Oxic to anoxic transition in bottom waters during formation of the Citronen Fjord sediment-hosted Zn-Pb deposit, North Greenland
Bulk geochemical data acquired for host sedimentary rocks to the Late Ordovician Citronen Fjord sediment-hosted Zn-Pb deposit in North Greenland constrain the redox state of bottom waters prior to and during sulphide mineralization. Downhole profiles for one drill core show trends for redox proxies (MnO, Mo, Ce anomalies) that suggest the local basin bottom waters were initially oxic, changing to
Authors
John F. Slack, Diogo Rosa, Hendrik Falck
PESTools – A Python toolkit for processing PEST-related information
PESTools is an open-source Python package for processing and visualizing information associated with
the parameter estimation software PEST and PEST++. While PEST output can be reformatted for post-
processing in spreadsheets or other menu-driven software packages, that approach can be error-prone
and time-consuming. Managing information from highly parameterized models with thousands of
parameter
Authors
Evan Christianson, Andrew T. Leaf
Preliminary analysis of suspended sediment rating curves for the Kalamazoo River and its tributaries from Marshall to Kalamazoo, Michigan
Suspended sediment concentration (SSC) rating curves for the Kalamazoo River and its tributaries from Marshall to Kalamazoo, Michigan, U.S.A., were developed based on measured data. The slopes of the atsite SSC rating curves were of two general types: either increasing or decreasing with increasing discharges. By examining the basin characteristics and flow patterns, streams with negative SSC rati
Authors
David T. Soong, Christopher J. Hoard, Faith A. Fitzpatrick, Ronald B. Zelt
Proceedings of the International Miconia Conference
This proceedings is a compilation of 15 of the 27 papers and posters that were presented at the 2009 International Miconia Conference. The Conference was held in Keanae Hawaii May 4th to 7th 2009, hosted by the Maui Invasive Species Committee. *No official abstract was available for the proceedings...K. Keck
Authors
L.L. Loope, J.-Y. Meyer, B. D. Hardesty, C. W. Smith
Processes limiting depth of arroyo incision: Examples from the Rio Puerco, New Mexico
We examined channel flow and suspended sediment transport processes within the lower Rio Puerco arroyo, located in semi-arid north-central New Mexico, in an attempt to answer the question: Why did arroyo incision stop by about 1936? Channel flow model results show that in the narrow, incised channel of 1936, the boundary shear stress during a large flood was highest over the lower banks and bank t
Authors
Eleanor R. Griffin, Jonathan M. Friedman
Quality assurance testing of acoustic doppler current profiler transform matrices
The U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility (HIF) is nationally responsible for the design, testing, evaluation, repair, calibration, warehousing, and distribution of hydrologic instrumentation in use within the USGS Water Mission Area (WMA). The HIF's Hydraulic Laboratory has begun routine quality assurance (QA) testing and documenting the performance of every USGS WMA a
Authors
Brandy Armstrong, Janice M. Fulford, Kirk G. Thibodeaux
Reaction modeling of drainage quality in the Duluth Complex, northern Minnesota, USA
Reaction modeling can be a valuable tool in predicting the long-term behavior of waste material if representative rate constants can be derived from long-term leaching tests or other approaches. Reaction modeling using the REACT program of the Geochemist’s Workbench was conducted to evaluate long-term drainage quality affected by disseminated Cu-Ni-(Co-)-PGM sulfide mineralization in the basal zon
Authors
Robert Seal, Kim Lapakko, Nadine M. Piatak, Laurel G. Woodruff
REE enrichment in granite-derived regolith deposits of the southeast United States: Prospective source rocks and accumulation processes
The Southeastern United States contains numerous anorogenic, or A-type, granites, which constitute promising source rocks for REE-enriched ion adsorption clay deposits due to their inherently high concentrations of REE. These granites have undergone a long history of chemical weathering, resulting in thick granite-derived regoliths, akin to those of South China, which supply virtually all heavy RE
Authors
Nora K. Foley, Robert A. Ayuso
Representativeness of soil samples collected to assess mining-related contamination of flood plains in southeast Kansas
Historical lead and zinc mining in the Tri-State Mining District (TSMD), located in parts of southeast Kansas, southwest Missouri, and northeast Oklahoma, has resulted in a substantial ongoing input of lead and zinc to the environment (Juracek, 2006; Juracek and Becker, 2009). In response to concern about the mining-related contamination, southeast Cherokee County, Kansas, was listed on the U.S. E
Authors
Kyle E. Juracek