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Abandoned Mine Drainage In The Swatara Creek Basin, Southern Anthracite Coalfield, Pennsylvania, Usa: 2. Performance Of Treatment Systems, Charles A. Cravotta III 2010 US Geological Survey, PA Water Science Center, 215 Limekiln Rd, New Cumberland, PA, USA

Abandoned Mine Drainage In The Swatara Creek Basin, Southern Anthracite Coalfield, Pennsylvania, Usa: 2. Performance Of Treatment Systems, Charles A. Cravotta Iii

USGS Staff -- Published Research

A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological Survey collected water-quality data at upstream and downstream locations relative to each system eight or more times annually for a minimum of 3 years at each site during 1996– 2007. Performance was normalized among treatment types by dividing the acid load removed by ...


Recent Advances In Global Lake Coring Hold Promise For Global Change Research In Paleolimnology, Walter E. Dean 2010 U.S. Geological Survey, Denver, CO

Recent Advances In Global Lake Coring Hold Promise For Global Change Research In Paleolimnology, Walter E. Dean

USGS Staff -- Published Research

Thank you, Antje, for your generous comments and I thank IPA for presenting me with this award along with three giants of paleolimnology! I am humbled and delighted to accept this award as a representative of all those in the Paleolimnology community whose creative insights continue to make Paleolimnology inspiring.


Mineralogical And Chemical Characteristics Of Some Natural Jarosites, George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Reinhard W. Leinz, Rhonda L. Driscoll 2010 U.S. Geological Survey, Box 25046, M.S. 973, Denver, CO 80225-0046, USA

Mineralogical And Chemical Characteristics Of Some Natural Jarosites, George A. Desborough, Kathleen S. Smith, Heather A. Lowers, Gregg A. Swayze, Jane M. Hammarstrom, Sharon F. Diehl, Reinhard W. Leinz, Rhonda L. Driscoll

USGS Staff -- Published Research

This paper presents a detailed study of the mineralogical, microscopic, thermal, and spectral characteristics of jarosite and natrojarosite minerals. Systematic mineralogic and chemical examination of a suite of 32 natural stoichiometric jarosite and natrojarosite samples from diverse supergene and hydrothermal environments indicates that there is only limited solid solution between Na and K at low temperatures, which suggests the presence of a solvus in the jarosite-natrojarosite system at temperatures below about 140 °C. The samples examined in this study consist of either end members or coexisting end-member pairs of jarosite and natrojarosite. Quantitative electron-probe microanalysis data for several natural hydrothermal ...


Hydrogeophysical Methods For Analyzing Aquifer Storage And Recovery Systems, Burke J. Minsley, Jonathan Ajo-Franklin, Amitabha Mukhopadhyay, Frank Dale Morgan 2010 U.S. Geological Survey

Hydrogeophysical Methods For Analyzing Aquifer Storage And Recovery Systems, Burke J. Minsley, Jonathan Ajo-Franklin, Amitabha Mukhopadhyay, Frank Dale Morgan

USGS Staff -- Published Research

Hydrogeophysical methods are presented that support the siting and monitoring of aquifer storage and recovery (ASR) systems. These methods are presented as numerical simulations in the context of a proposed ASR experiment in Kuwait, although the techniques are applicable to numerous ASR projects. Bulk geophysical properties are calculated directly from ASR flow and solute transport simulations using standard petrophysical relationships and are used to simulate the dynamic geophysical response to ASR. This strategy provides a quantitative framework for determining site-specific geophysical methods and data acquisition geometries that can provide the most useful information about the ASR implementation. An axisymmetric, coupled ...


Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig 2010 Colorado State University - Fort Collins

Evidence For Recent Population Bottlenecks In Northern Spotted Owls (Strix Occidentalis Caurina), W. Chris Funk, Eric D. Forsman, Matthew Johnson, Thomas D. Mullins, Susan M. Haig

USGS Staff -- Published Research

The northern spotted owl (Strix occidentalis caurina) is one of the most controversial threatened subspecies ever listed under the US Endangered Species Act. Despite protection of its remaining forest habitat, recent field studies show continued declines of northern spotted owls. One potential threat to northern spotted owls which has not yet been shown is loss of genetic variation from population bottlenecks. Bottlenecks can increase the probability of mating among related individuals, potentially causing inbreeding depression, and can decrease adaptive potential. Here we report evidence for recent bottlenecks in northern spotted owls using a large genetic dataset (352 individuals and 10 ...


The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler 2010 U.S. Geological Survey

The Cleaning Of Burned And Contaminated Archaeological Maize Prior To 87sr/86sr Analysis, L.V. Benson, H. E. Taylor, T. I. Plowman, D. A. Roth, R. C. Antweiler

USGS Staff -- Published Research

Accurate trace-metal and strontium-isotope analyses of archaeological corn cobs require that metal contaminants be removed prior to chemical analysis. Archaeological cobs are often coated with construction debris, dust, or soilwhich contains mineral particles. In addition, most archaeological cobs are partially or completely burned and the burned parts incorporate mineral debris in their hardened residual structures. Unburned cobs are weak ion exchangers and most metals within a cob are not firmly bound to cob organic matter; therefore, immersing cobs in acids and rinsing them in deionized water to remove mineral contaminants may result in the undesirable loss of metals, including strontium ...


Enhanced Late Holocene Enso/Pdo Expression Along The Margins Of The Eastern North Pacific, John A. Barron, Lesleigh Anderson 2010 USGS

Enhanced Late Holocene Enso/Pdo Expression Along The Margins Of The Eastern North Pacific, John A. Barron, Lesleigh Anderson

USGS Staff -- Published Research

Pacific climate is known to have varied during the Holocene, but spatial patterns remain poorly defined. This paper compiles terrestrial and marine proxy data from sites along the northeastern Pacific margins and proposes that they indicate 1) suppressed ENSO conditions during the middle Holocene between ~8000 and 4000 cal BP with a North Pacific that generally resembled a La Niña-like or more negative PDO phase and 2) a climate transition between ~4200 and 3000 cal BP that appears to be the teleconnected expression to a more modern-like ENSO Pacific. Compared to modern day conditions, the compiled data suggest that during ...


Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver 2010 Caterpillar, Inc.

Virtual Reality For Assembly Methods Prototyping: A Review, Abbishek Seth, Judy M. Vance, James H. Oliver

Mechanical Engineering Publications

Assembly planning and evaluation is an important component of the product design process in which details about how parts of a new product will be put together are formalized. A well designed assembly process should take into account various factors such as optimum assembly time and sequence, tooling and fixture requirements, ergonomics, operator safety, and accessibility, among others. Existing computer-based tools to support virtual assembly either concentrate solely on representation of the geometry of parts and fixtures and evaluation of clearances and tolerances or use simulated human mannequins to approximate human interaction in the assembly process. Virtual reality technology has ...


Vulnerability Analysis Of Rfid Protocols For Tag Ownership Transfer, Pedro PERIS-LOPEZ, Julio Hernandez-Castro, Juan Tapiador, Tieyan LI, Yingjiu LI 2010 Singapore Management University

Vulnerability Analysis Of Rfid Protocols For Tag Ownership Transfer, Pedro Peris-Lopez, Julio Hernandez-Castro, Juan Tapiador, Tieyan Li, Yingjiu Li

Research Collection School Of Information Systems

In RFIDSec’08, Song proposed an ownership transfer scheme, which consists of an ownership transfer protocol and a secret update protocol [7]. The ownership transfer protocol is completely based on a mutual authentication protocol proposed in WiSec’08 [8]. In Rizomiliotis et al. (2009) [6], van Deursen and Radomirovic (2008), the first weaknesses to be identified (tag and server impersonation) were addressed and this paper completes the consideration of them all. We find that the mutual authentication protocol, and therefore the ownership transfer protocol, possesses certain weaknesses related to most of the security properties initially required in protocol design: tag ...


Scale‐Invariant Stress Orientations And Seismicity Rates Near The San Andreas Fault, Amy Day-Lewis, Mark D. Zoback, Stephen Hickman 2010 Stanford University

Scale‐Invariant Stress Orientations And Seismicity Rates Near The San Andreas Fault, Amy Day-Lewis, Mark D. Zoback, Stephen Hickman

USGS Staff -- Published Research

We analyzed measurements of the direction of maximum horizontal compressive stress as a function of depth in two scientific research wells near the San Andreas Fault in central and southern California. We found that the stress orientations exhibit scale‐invariant fluctuations over intervals from tens of cm to several km. Similarity between the scaling of the stress orientation fluctuations and the scaling of earthquake frequency with fault size suggests that these fluctuations are controlled by stress perturbations caused by slip on faults of various sizes in the critically‐stressed crust adjacent to the fault. The apparent difference in stress scaling ...


In-Situ Stress And Fracture Characterization For Planning Of An Egs Stimulation In The Desert Peak Geothermal Field, Nevada, Stephen H. Hickman, Nicholas C. Davatzes 2010 U.S. Geological Survey

In-Situ Stress And Fracture Characterization For Planning Of An Egs Stimulation In The Desert Peak Geothermal Field, Nevada, Stephen H. Hickman, Nicholas C. Davatzes

USGS Staff -- Published Research

An integrated study of natural fracture geometry, fluid flow and stress was conducted in Desert Peak well 27-15 in preparation for development of an Enhanced Geothermal System (EGS) through hydraulic stimulation. This stimulation will be carried out at depths of ~3000 to 3500 ft in units comprised of silicified rhyolite tuffs and metamorphosed mudstones at ambient temperatures of ~180 to 195° C. Our previous analyses of borehole image logs from this well showed that the current minimum horizontal principal stress, Shmin, is oriented 114 ± 17º and that numerous fractures in the planned stimulation interval are optimally oriented for normal faulting ...


Microbial Production Of Isotopically Light Iron(Ii) In A Modern Chemically Precipitated Sediment And Implications For Isotopic Variations In Ancient Rocks, G. E. Tangalos, B. L. Beard, C. M. Johnson, Charles N. Alpers, E. S. Shelobolina, H. Xu, H. Konishi, E. E. Roden 2010 University of Wisconsin - Madison

Microbial Production Of Isotopically Light Iron(Ii) In A Modern Chemically Precipitated Sediment And Implications For Isotopic Variations In Ancient Rocks, G. E. Tangalos, B. L. Beard, C. M. Johnson, Charles N. Alpers, E. S. Shelobolina, H. Xu, H. Konishi, E. E. Roden

USGS Staff -- Published Research

The inventories and Fe isotope composition of aqueous Fe(II) and solid-phase Fe compounds were quantified in neutral-pH, chemically precipitated sediments downstream of the Iron Mountain acid mine drainage site in northern California, USA. The sediments contain high concentrations of amorphous Fe(III) oxyhydroxides [Fe(III)am] that allow dissimilatory iron reduction (DIR) to predominate over Fe–S interactions in Fe redox transformation, as indicated by the very low abundance of Cr(II)-extractable reduced inorganic sulfur compared with dilute HCl-extractable Fe. δ56Fe values for bulk HCl- and HF-extractable Fe were ≈ 0. These near-zero bulk δ56Fe ...


The Horizontal Electric Field Induced By A Lightning Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner 2010 Trinity University

The Horizontal Electric Field Induced By A Lightning Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner

Physics and Astronomy Faculty Research

Problem statement: Develop a new formula which describes the horizontal electric field induced by a lightning return stroke in contact with an imperfect conductive surface. Approach: A new method for describing the horizontal electric field induced by a lightning return stroke will be presented. The method presented here had utilized an approach which purposely downplayed the physics of how image theory was employed in the presence of an imperfect conductive surface. It did so by adopting a technique which had focused on the geometry that existed between the lightning channel and surface ground. In doing so, new expressions for surface ...


The Magnetic Field Induced By A Lightning Strikes Indirect Effect Double Exponential Current Waveform, S L. Meredith, S K. Earles, I N. Kostanic, Niescja E. Turner 2010 Trinity University

The Magnetic Field Induced By A Lightning Strikes Indirect Effect Double Exponential Current Waveform, S L. Meredith, S K. Earles, I N. Kostanic, Niescja E. Turner

Physics and Astronomy Faculty Research

Problem statement: Develop a new formula which describes the magnetic field induced by a lightning strike's indirect effect double exponential current waveform. Approach: A novel approach for developing a closed-form solution for the magnetic field from the indirect effect double exponential current waveform will be presented. In the literature, models typically employ the pulse waveform to derive the corresponding electromagnetic fields. However, given the Department of Defense (DoD) has incorporated the double exponential current waveform as part of their "Electromagnetic Environmental Effects Requirements For Systems", we felt it important to develop a solution for the magnetic field which utilized ...


Bayesian Models And Decision Algorithms For Complex Early Phase Clinical Trials, Peter F. Thall 2010 SelectedWorks

Bayesian Models And Decision Algorithms For Complex Early Phase Clinical Trials, Peter F. Thall

Peter F. Thall

No abstract provided.


Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff 2010 Iowa State University

Swine Producer Appraisal Of The Community Assessment Model For Odor Dispersion (Cam), John C. Tyndall, Jay D. Harmon, Steven J. Hoff

Agricultural and Biosystems Engineering Publications

The community assessment model (CAM) for odor dispersion is a tool to assist in the siting of swine production facilities. CAM considers the size and type of a swine production system, local historical weather conditions, and odor control implementation. It predicts the number of hours of exposure to various levels of odor, by month, for each receptor in a given community. A follow-up survey of all CAM users since 2005 was conducted. The survey was designed to provide: 1) formative feedback for programming adjustments to improve Extension efficiency, usability, and reduce costs; and 2) summative feedback used to provide an ...


The Rainfall Over Tropical South America Generated By Multiple Scale Processes, Carlos Mauricio Carrillo 2010 Iowa State University

The Rainfall Over Tropical South America Generated By Multiple Scale Processes, Carlos Mauricio Carrillo

Graduate Theses and Dissertations

The rainfall regime over Central America and tropical South America is the most important hydro-meteorological event in the tropics after the Asian-Australian monsoon system. Therefore, in this study we analyzed how the tropical rainfall over tropical South America is developed using a multiple time and space scale approach.

It was found that the rainfall regime is affected mainly by the ENSO, showing two opposite phases not only in the precipitation, but also in the dynamics terms. Although, there is an advance understanding of the role of the intraseasonal mode of the global tropical precipitation, documentation of the role of the ...


Seasonal Hydrologic Trends In Iowa Watersheds Over The Last Half Of The 20th Century, Kayla Jo Conrad 2010 Iowa State University

Seasonal Hydrologic Trends In Iowa Watersheds Over The Last Half Of The 20th Century, Kayla Jo Conrad

Graduate Theses and Dissertations

Climate change is expected to cause significant changes in the global hydrologic cycle, yet the impact to regional hydrology is not well known for the Midwest U.S. As a first step in understanding the impact of climate change in Iowa watersheds, historical streamflow observations and model-derived time series of soil moisture, frozen ground and snow cover for ten Iowa watersheds were analyzed. The modeled data were generated using precipitation and temperature data spanning 1948 to 2003 as inputs to the conceptually-based hydrologic models of the National Weather Service river forecasting system. The models were calibrated for each watershed using ...


Statisical Method And Simulation On Detecting Cracks In Vibrothermography Inspection, Chunwang Gao 2010 Iowa State University

Statisical Method And Simulation On Detecting Cracks In Vibrothermography Inspection, Chunwang Gao

Graduate Theses and Dissertations

Vibrothermography is a nondestructive evaluation method that can be

used to detect cracks in specimens and it is the main engineering

technique we focused in this thesis. This study can be separated into

three parts. In the first part, we develop a systematic statistical

method to provide a detection algorithm to automatically analyze the

data generated in Sonic IR inspections. Principal components analysis

(PCA) was used for dimension reduction. Robust regression and cluster

analysis are used to find the maximum studentized residual (MSD) for

crack detection. The procedure proved to be both more efficient and

more accurate than human inspection ...


Understanding And Improving Cloud And Radiation Processes Using Year-Long Cloud-Resolving Model Simulations, Sunwook Park 2010 Iowa State University

Understanding And Improving Cloud And Radiation Processes Using Year-Long Cloud-Resolving Model Simulations, Sunwook Park

Graduate Theses and Dissertations

The representation of subgrid cloud variability and its impact on radiation has been a challenge in general circulation model (GCM) simulations. To improve the representation of cloud and radiative variability and their interactions within a GCM grid, it is essential to understand subgrid cloud structures and their statistics based on long-term cloud and radiation data for various climate regions. In this study, year-long cloud-resolving model (CRM) simulations forced with the Atmospheric Radiation Measurement (ARM) large-scale forcing and prescribed evolving surface albedo were conducted for the year 2000 to document the characteristics of cloud horizontal inhomogeneity and vertical overlap and to ...


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