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Full-Text Articles in Earth Sciences

High-Resolution Ground-Penetrating Radar Profiles Of Perennial Lake Ice In The Mcmurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, And Subbottom, Hilary A. Dugan, Steven A. Arcone, Maciej K. Obryk, Peter T. Doran Jan 2016

High-Resolution Ground-Penetrating Radar Profiles Of Perennial Lake Ice In The Mcmurdo Dry Valleys, Antarctica: Horizon Attributes, Unconformities, And Subbottom, Hilary A. Dugan, Steven A. Arcone, Maciej K. Obryk, Peter T. Doran

Geology Faculty Publications and Presentations

Ground-penetrating radar (GPR) is not commonly used to study lake ice, and in general, the ground-based use of radar frequencies greater than 500 MHz in cryosphere geophysics is rare, due to a general interest in deeper stratigraphy and the difficulty of extensive profiling over rough snow surfaces. Our goal was to find further information on the origin of the deposition and formation of intra-ice layers, bottom topography, and subbottom deposits using GPR with pulses centered near 850 MHz on two permanently ice-covered lakes in the Mc- Murdo Dry Valleys, Antarctica. The profiles were obtained using a one-person sled operation over …


Subsurface Fluid Flow Through The Mississippian Section Of North-Central Oklahoma, Carolyn Brown May 2015

Subsurface Fluid Flow Through The Mississippian Section Of North-Central Oklahoma, Carolyn Brown

Graduate Theses and Dissertations

This study consisted of using drill stem tests, seismic amplitude data, and well logs to create the parameters needed to construct a groundwater flow model for a portion of Osage County. At the start, a potentiometric map of Osage County, Oklahoma was generated to use as a basis for the initial hydraulic heads and the constant heads in the model. Next, three seismic amplitude images were produced in a seismic interpretation program, OpenDtect, to base the hydraulic conductivity values on. In addition, utilizing Gamma Ray on 12 separate wells east-west across the county, a structural cross-section was created within Petra. …


Inference Of Hydrogeological Conditions And Source History Of Groundwater Contaminants Using 3-D Modeling And Human Health Risk Assessment, Mary Rosanna Carnagie Jan 2015

Inference Of Hydrogeological Conditions And Source History Of Groundwater Contaminants Using 3-D Modeling And Human Health Risk Assessment, Mary Rosanna Carnagie

Wayne State University Theses

This study was completed using data interpolation and human health risk modules in Spatial Analysis and Decision Assistance (SADA) software to model a 3-D time-series of 1,4-dioxane and vinyl chloride plumes and their associated health risks to infer hydrogeological conditions at the Ann Arbor Landfill site. Ordinary kriging estimates of contaminant distribution and human health risk distribution provide insight to groundwater flow direction, hydraulic conductivity distribution, and source history of contaminants at sites with groundwater contamination in a glacial aquifer system. More studies with larger datasets in glacial aquifer systems are necessary to prove these correlations, but this thesis illustrates …


Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton Jan 2015

Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton

Electronic Theses and Dissertations

Long-term groundwater level and stream stage measurements at a USGS coupled groundwater stream-gaging station located on the Sunflower River in Sunflower, MS show an apparent stage-threshold for infiltration to the underlying alluvial aquifer. This site is located near the center of a large regional groundwater cone of depression in the Mississippi River Valley alluvial aquifer. The USGS well (termed well 3 in this study) was thought to be completed in the regional shallow aquifer, though often recording anomalously high water levels relative to other wells in the region. The purpose of this research was to identify the responsible mechanism for …


Integrating Gis And Hydrology For Flood Risk Analysis, Anas B. Rabie Apr 2014

Integrating Gis And Hydrology For Flood Risk Analysis, Anas B. Rabie

Theses and Dissertations

Spatial analysis using GIS was evaluated for its ability to predict the potential hazard of a flood event in the Illinois River region in the State of Illinois. The data employed in the analysis are available to the public from trusted organizations such as Illinois State Geological Survey (ISGS), and the US Geological Survey (USGS). The purposes of this study are to 1) examine the applicability of GIS spatial analysis to determine flood inundation risk, and 2) to determine how to do so with the least amount of data possible, while still producing an accurate flood inundation risk map. This …


Effect Of Rivers On Groundwater Temperature In Heterogeneous Buried-Valley Aquifers: Extent, Attenuation, And Phase Lag Of Seasonal Variation, Nathan Lee Young Jan 2014

Effect Of Rivers On Groundwater Temperature In Heterogeneous Buried-Valley Aquifers: Extent, Attenuation, And Phase Lag Of Seasonal Variation, Nathan Lee Young

Browse all Theses and Dissertations

The temperature of groundwater in aquifers is relatively stable when compared to the water temperature in surface-water bodies. However, in aquifers that are hydraulically connected to rivers that have water flux into the aquifer, the local aquifer temperature can show seasonal variation. This project focused on the thermally-altered, near-river zone of such an aquifer, and used numerical methods to examine the extent of seasonal variation in temperature into the aquifer, and the attenuation and phase shift of the signal with distance from the river. The results show that the extent of alteration by diffusive heat flow is negligible compared to …


Hydrogeologic Variations Across A Barrier Island That Influence Inter-Dune Wetlands False Cape State Park, Virginia, Matthew Collier Richardson Oct 2013

Hydrogeologic Variations Across A Barrier Island That Influence Inter-Dune Wetlands False Cape State Park, Virginia, Matthew Collier Richardson

OES Theses and Dissertations

False Cape State Park in southeastern Virginia Beach, Virginia contains a transgressive barrier island complex. Inter-dune swales located on the eastern coast of the barrier island contain soils that experience hydric conditions. However, these swales lack the prolonged presence of hydric soil indicators that are necessary for a site to be officially recognized as a jurisdictional wetland. The appearance and subsequent disappearance of redoximorphic wetland soil features in the young, sandy soils of the inter-dune swales here may stem from changes in the patterns of groundwater recharge and discharge across the island. These soils are being monitored by the Mid …


Assessment And Conceptualization Of Groundwater Flow In The Edwards Aquifer Through The Knippa Gap In Uvalde County, Texas, Jennifer Raye Adkins Aug 2013

Assessment And Conceptualization Of Groundwater Flow In The Edwards Aquifer Through The Knippa Gap In Uvalde County, Texas, Jennifer Raye Adkins

Graduate Theses and Dissertations

The Edwards aquifer is one of the major regional karst aquifers in the United States, with an average withdrawal of 950 million liters per day (L/d). This investigation focuses on the connection between the Uvalde pool and the San Antonio pool of the Edwards aquifer, known as the Knippa Gap, west of the San Antonio metropolitan area in Uvalde County. This is a major zone of recharge to the Edwards aquifer and is approximately 6.4 km wide. The Knippa Gap is bounded by northeast trending faults of the Balcones Fault Zone (BFZ) on the north (specifically the Cooks and Trio …


The Evaluation Of Water Storage In Death Valley Using Grace Satellite Data, Maile Sweigart May 2013

The Evaluation Of Water Storage In Death Valley Using Grace Satellite Data, Maile Sweigart

UNLV Theses, Dissertations, Professional Papers, and Capstones

As drought conditions spread across the United States, concerns over water supplies, water use, and water management policies are growing and possible contributing environmental factors are continually being scrutinized. This thesis examines Death Valley as an analog for Southern Nevada and utilizes NASA EOS data, combined with ancillary climate data, to assess the effect of decadal climate variability on groundwater storage in the Death Valley area. Historical climate data, combined with satellite imagery observations, were compiled and calculated for analyses. Conclusions derived from statistical analyses infer trends between GRACE (Gravity Recovery and Climate Experiment) satellite data and fluctuating levels of …


Caves And Karst Hydrology Of The Mariana Islands (Abstract), Kevin W. Stafford Jan 2013

Caves And Karst Hydrology Of The Mariana Islands (Abstract), Kevin W. Stafford

Faculty Publications

Abstract Attached


Stratigraphic Constraints On Groundwater Flow: Examples From York College, Cuny Campus In Queens, New York City, Nazrul I. Khandaker, Stanley Schleifer, Ezazul Haque, Coreyn Goddard, Shirley Jackson Jan 2013

Stratigraphic Constraints On Groundwater Flow: Examples From York College, Cuny Campus In Queens, New York City, Nazrul I. Khandaker, Stanley Schleifer, Ezazul Haque, Coreyn Goddard, Shirley Jackson

Publications and Research

Surficial geology of the York College campus is dominated by recent glacial deposits dating back to late Wisconsinan event. Several shallow excavation-type trenches reaching a depth of approximately 6 to 10 feet were dug in the wide greeneries adjacent to the parking lot to determine soil texture and collect in-situ permeability data. Based on these shallow pits, an apparent subsurface stratigraphy has been constructed. In general, the uppermost 8 to 18 inches is mostly clayey-and-silty sand and organic-rich top soil overlying stratified drift. The uppermost horizons are observed to also contain fill materials such as bricks, concretes, broken glasses, and …


A Localized Investigation Of High Resolution Groundwater Flow Properties Of The Saginaw Aquifer Mason, Michigan, Amanda Hayden Jun 2012

A Localized Investigation Of High Resolution Groundwater Flow Properties Of The Saginaw Aquifer Mason, Michigan, Amanda Hayden

Masters Theses

High resolution groundwater models can aid in better management of groundwater resources through more accurate characterization and quantification of aquifer systems. Detailed assessments of flow properties in the context of sedimentary facies can provide high quality data input for more accurate groundwater models.

The Pennsylvanian Grand River and Saginaw bedrock formations comprise the Saginaw Aquifer located in the Lansing, Michigan Tri-County region. The Saginaw Aquifer consists of a predominately shale and sandstone successions. These sandstone facies range up to 40 meters thick, and supply a significant amount water resources to the Lansing Tri-County area. Data used in this study was …


Weaber Plain Hydrogeology: Preliminary Results, Richard J. George Dr, John Andrew Simons, Paul Raper, Robert J. Paul, D L. Bennett, Rosemary H. Smith Jun 2011

Weaber Plain Hydrogeology: Preliminary Results, Richard J. George Dr, John Andrew Simons, Paul Raper, Robert J. Paul, D L. Bennett, Rosemary H. Smith

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain. Construction of the M2 supply channel connecting the ORIA and Weaber Plain, and the final period of irrigation design, environmental management and related approval processes commenced later in 2009. This process followed a protracted period of public and private industry planning and environmental assessment (Kinhill 2000). As a part of the environmental planning and approvals process, the WA Government was required to prepare a groundwater management plan and a hydrodynamic plan. These plans were to address potential issues …


Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North Jan 2011

Proceedings Of The 2011 International Conference On Karst Hydrogeology And Ecosystems, Jason Samuel Polk, Leslie A. North

Environmental Sustainability Books

Jointly sponsored by the Hoffman Environmental Research Institute, the National Cave & Karst Research Institute, and the International Association of Hydrogeologists, the 2011 International Conference on Karst Hydrogeology and Ecosystems was held at Western Kentucky University in Bowling Green, Kentucy on 8-10 June 2011. Topics include karst geomorphology, engineering and modeling, isotope geochemistry, and cultural and educational aspects of karst environments.


Miscible Column Studies Of Unfractured And Saturated Cores Of Topopah Spring Tuff From Yucca Mountain, Nevada Using Hydrophobic Organic Pollutants, Kody V. Kramer Jan 2011

Miscible Column Studies Of Unfractured And Saturated Cores Of Topopah Spring Tuff From Yucca Mountain, Nevada Using Hydrophobic Organic Pollutants, Kody V. Kramer

LSU Master's Theses

Miscible displacement column studies were conducted on unfractured cores of Topopah Spring Tuff to quantify transport characteristics of bromide&44; pentafluorobenzoic acid &40;PFBA&41;&44; trichloroethylene &40;TCE&41;&44; and naphthalene. Three 5 cm diameter by 2 cm long cores were flushed with pulses of simulated groundwater containing these tracers&44; followed by tracer&45;free solution. Effective porosities were gravimetrically measured as 11&37;&44; 10.6&37;&44; and 9.5&37;. The tracers achieved full breakthrough in an order correlating to their hydrophobicities. Bromide and PFBA sorbed least&44; achieving full breakthrough in fewer than 10 pore volumes. As water analogues&44; both exhibited no quantifiable sorption. Delay to full breakthrough was contributed to …


Comment On ‘‘An Unconfined Groundwater Model Of The Death Valley Regional Flow System And A Comparison To Its Confined Predecessor’’ By R.W.H. Carroll, G.M. Pohll And R.L. Hershey [Journal Of Hydrology 373/3–4, Pp. 316–328], Claudia C. Faunt, Alden M. Provost, Mary C. Hill, Wayne R. Belcher Jan 2011

Comment On ‘‘An Unconfined Groundwater Model Of The Death Valley Regional Flow System And A Comparison To Its Confined Predecessor’’ By R.W.H. Carroll, G.M. Pohll And R.L. Hershey [Journal Of Hydrology 373/3–4, Pp. 316–328], Claudia C. Faunt, Alden M. Provost, Mary C. Hill, Wayne R. Belcher

United States Geological Survey: Staff Publications

Carroll et al. (2009) state that the United States Geological Survey (USGS) Death Valley Regional Flow System (DVRFS) model, which is based on MODFLOW, is ‘‘conceptually inaccurate in that it models an unconfined aquifer as a confined system and does not simulate unconfined drawdown in transient pumping simulations.’’ Carroll et al. (2009) claim that ‘‘more realistic estimates of water availability’’ can be produced by a SURFACT-based model of the DVRFS that simulates unconfined groundwater flow and limits withdrawals from wells to avoid excessive drawdown. Differences in results from the original MODFLOW- based model and the SURFACT-based model stem primarily from …


Investigation Of Spatial And Temporal Processes Of Lake–Aquifer Interactions In The Nebraska Sand Hills, John T. Ong Dec 2010

Investigation Of Spatial And Temporal Processes Of Lake–Aquifer Interactions In The Nebraska Sand Hills, John T. Ong

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Interaction between surface water and groundwater is an important component of the water cycle that affects the physicochemical and biological characteristics of lakes, streams, wetlands, and seacoasts. Due to the complex interaction of geologic, topographic, and hydrologic factors, flow between lakes and groundwater remains poorly understood. Evolution of conceptual models over the past 30 years describes processes of advection, dispersion, and free convection that occur in different lake flow regimes. Few detailed field studies document the validity of these conceptual models because of the difficulty of studying the subsurface and the prohibitive cost of instrumenting large areas. In the semi-arid …


Feasibility Of Extending An Artificial Salmon Spawning Stream, Marx Creek Near Hyder, Alaska, Tom Nelson May 2010

Feasibility Of Extending An Artificial Salmon Spawning Stream, Marx Creek Near Hyder, Alaska, Tom Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Marx Creek, near Hyder in southeast Alaska, is a groundwater-fed, artificial salmon-spawning stream that was constructed to enhance the habitat of the atypically large chum salmon. The success of the upper Marx Creek has been limited primarily by the infiltration of silty water from the Salmon River through its flood-control dike, which results in a turbid stream environment that is not conducive to salmon spawning.

The purpose of this project was to determine whether baseflow from the groundwater system is sufficient to support a proposed 1,000-foot extension of Marx Creek. The extension would be constructed approximately 500 feet east of …


Geochemical Spatial Variability Of The Colorado River Associated With Karst Springs, Colorado Bend State Park, Central Texas [Abstract], Katie Mitchell, Sherri Dornak, Kevin W. Stafford Jan 2010

Geochemical Spatial Variability Of The Colorado River Associated With Karst Springs, Colorado Bend State Park, Central Texas [Abstract], Katie Mitchell, Sherri Dornak, Kevin W. Stafford

Faculty Presentations

No abstract provided.


An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig Jan 2010

An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig

Technical Bulletins

The inventory and condition survey of the Western Australian part of the Nullarbor region, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 2005 and 2007, describes and maps the natural resources of the region. This survey report provides a baseline record of the existence and condition of the area's natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The Nullarbor region has …


Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet Jan 2010

Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet

International Journal of Speleology

The Choranche Cave system (Vercors, France) is an excellent locality for measuring the growth rates of large numbers soda straws. This is especially the case for the Coufin Cave, as enlargement of the cave entrance in 1875 led to a change in stalactite color from brown to white, thus providing a reliable chronomarker. The date of this brown-to-white calcite transition has been confirmed by lamina counting. We measured and georeferenced the growth-lengths of 306 soda straws in a 1m2 area of the roof of the Coufin Cave entrance chamber. Because of the very slow and sometimes inexistent water feeding …


Analysis Of Electromagnetic And Seismic Geophysical Methods For Investigating Shallow Sub-Surface Hydrogeology, Eric M. Parks Dec 2009

Analysis Of Electromagnetic And Seismic Geophysical Methods For Investigating Shallow Sub-Surface Hydrogeology, Eric M. Parks

Theses and Dissertations

An integrated electromagnetic (EM) and seismic geophysical study was performed to evaluate non-invasive approaches to estimate depth to shallow groundwater in arid environments with elevated soil salinity where the installation of piezometers would be impractical or prohibited. Both methods were tested in two study areas (semi-arid and arid respectively), one in Palmyra, Utah, USA near the shore of Utah Lake where groundwater is shallow and unconfined in relatively homogeneous lacustrine sediments. The other area is Carson Slough, Nevada, USA near Ash Meadows National Wildlife Refuge in Amargosa Valley. The area is underlain by valley fill, with generally variable shallow depths …


Biogeochemical Behavior Of Dissolved Arsenic And Uranium Concentrations In Public Water Supply Wells, Kevin J. Mcvey May 2009

Biogeochemical Behavior Of Dissolved Arsenic And Uranium Concentrations In Public Water Supply Wells, Kevin J. Mcvey

School of Natural Resources: Dissertations, Theses, and Student Research

Public water supply (PWS) wells currently contain dissolved uranium concentrations above the federally mandated maximum contaminant level (MCL) of 30 ppb (parts per billion) and dissolved arsenic concentrations above the 10 ppb MCL. Both uranium and arsenic are known to cause various forms of cancer in humans. Variations in total uranium concentrations in PWS wells in Nebraska indicate a relationship to the duration and rate of pumping in specific wells. Although total arsenic concentrations show some variability over time in specific wells, the relationship to pumping is not as clear. Previous studies show that iron and sulfur bacteria present in …


The Southeastern Coastal Plain: An Overview, Lee J. Florea, H. L. Vacher Jan 2009

The Southeastern Coastal Plain: An Overview, Lee J. Florea, H. L. Vacher

Earth, Environmental, and Atmospheric Sciences Faculty Publications

No abstract provided.


Porosity And Permeability In Ternary Sediment Mixtures, Jason Dennis Esselburn Jan 2009

Porosity And Permeability In Ternary Sediment Mixtures, Jason Dennis Esselburn

Browse all Theses and Dissertations

Porosity and permeability were measured in mixtures of fine, medium, and coarse sand, where the volume fraction of each of the three components was systematically varied. The porosity varies non-linearly with the volume fractions, and can be modeled with a piecewise-linear approach. The permeability also varies non-linearly with the volume fractions. Permeability can be modeled with the Kozeny-Carman equation using a recursive approach for computing the representative grain size from those of the components in the mixture.


Thermo-Mineral Waters From The Cerna Valley Basin (Romania), Ioan Povara, Georgel Simion, Constantin Marin Nov 2008

Thermo-Mineral Waters From The Cerna Valley Basin (Romania), Ioan Povara, Georgel Simion, Constantin Marin

Studia UBB Geologia

In the south-west of the Southern Carpathians, upstream from the confluence of Cerna with Belareca, an aquifer complex has developed, strongly influenced by hydrogeothermal phenomena, acting within two major geological structures, the Cerna Syncline and the Cerna Graben. The complex consists mainly in Jurassic and Cretaceous carbonate rocks, as well as in the upper part of the Cerna Granite, highly fractured, tectonically sunken into the graben. As a result of the tectonic processes which occurred after the end of the Jurassic-Cretaceous sedimentation cycle, limestones may be encountered at 1100 m altitude in the Mehedinţi Mountains, at 150 ¬¬600 m in …


Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat Jan 2008

Characterization Of Natural Spring Waters Of The San Bernardino Mountains Using Stable Isotopes Of Oxygen And Hydrogen, Alison Renee Sloat

Theses Digitization Project

The purpose of this study was to characterize the natural spring waters of the San Bernardino Mountains using two stable isotopes. The isotopic results of this study will aid with tracing sources, movements, and mixing effects on groundwater receiving mountain-front recharge in the region.


Percolation-Based Techniques For Upscaling The Hydraulic Conductivity Of Semi-Realistic Geological Media, Bilal Idriss Jan 2008

Percolation-Based Techniques For Upscaling The Hydraulic Conductivity Of Semi-Realistic Geological Media, Bilal Idriss

Browse all Theses and Dissertations

I tested three schemes for "upscaling" the hydraulic conductivity (K) on aquifers with bimodal K distributions. This bimodality (e.g., sand and mud deposits) was intended to capture typical geological conditions. Results were tested with a numerical model. Upscaling techniques used were inspired by schemes interpolating between arithmetic and harmonic means, but are based on percolation theory: 1) Critical path analysis (CPA), 2) Percolation path analysis (PPA, or standard scaling), and a novel scaling approach. Models chosen were both spatially correlated and uncorrelated, with important differences in critical percolation probabilities, Pc. Volume fractions Ps and 1-Ps (with Ps = sand volume …


The Role Of The Epikarst In Karst And Cave Hydrogeology: A Review, Paul W. Williams Jan 2008

The Role Of The Epikarst In Karst And Cave Hydrogeology: A Review, Paul W. Williams

International Journal of Speleology

The epikarst (also known as the subcutaneous zone) comprises highly weathered carbonate bedrock immediately beneath the surface or beneath the soil (when present) or exposed at the surface. Porosity and permeability are higher near the surface than at depth, consequently after recharge percolating rainwater is detained near the base of the epikarst, the detention ponding producing an epikarstic aquifer. Such an aquifer is found only where the uppermost part of the vadose zone is very weathered compared to the bedrock at depth. Sometimes this contrast in porosity and permeability does not occur either because the epikarst has been scraped off …


Tracer Tests In Karst Hydrogeology And Speleology, Nico Goldscheider, Joe Meiman, Michiel Pronk, Christopher Smart Jan 2008

Tracer Tests In Karst Hydrogeology And Speleology, Nico Goldscheider, Joe Meiman, Michiel Pronk, Christopher Smart

International Journal of Speleology

This article presents an introduction to the fundamentals of tracing techniques and their application in cave and karst environments, illustrated by case studies from the Mammoth Cave, USA, and a small experimental site in Switzerland. The properties and limitations of the most important artificial tracers are discussed, and the available methods of tracer injection, sampling, online monitoring and laboratory analysis are presented. Fully quantitative tracer experiments result in continuous or discrete concentration-time data series, i.e. breakthrough curves, and concomitant discharge data, which make it possible to obtain detailed information about groundwater flow and contaminant transport. Within the frame of speleological …