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Full-Text Articles in Physical Sciences and Mathematics

Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann Dec 2012

Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann

Graduate Theses and Dissertations

Archaeological investigations in the Emirate of Dubai, UAE conducted by the Dubai Department of Archaeology and the University of Arkansas demonstrate that the desert inland of the Oman Peninsula was occupied not only during the Arabian Neolithic (8000-4400 BC), when the region experienced a moist period referred to as the Holocene Climatic Optimum (HCO), but also during the more arid millennia following the decline of the HCO into the Christian Era. During this period, desert settlement clustered near a band of oases, in contrast to the more widespread spatial distribution of remains of nomadic pastoralists from the Neolithic. Excavations at …


Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt Dec 2012

Stratigraphic Variations In The Carboniferous Section Across The Arkansas-Oklahoma State Line Arch, Tyler Dean Engelhardt

Graduate Theses and Dissertations

The State Line Arch is represented by a structural high that trends through the study area in a loose alignment with the Arkansas-Oklahoma state line. Evidence of the arch extending further to the north includes a structural high and stratigraphic variation at an outcrop on Highway 59 near Evansville Mountain in Crawford County, Arkansas. The exact timing of the formation of the arch remains undetermined, but upper Devonian thinning at the top of the arch indicates the structure is pre-Mississippian. The reason for the development of the arch is poorly understood, but evidence linking Mississippian-aged Waulsortian mounds to Precambrian Spavinaw …


Assessing The Impacts Of Surface Water Removal For Use In Natural Gas Extraction On A Watershed Level, Carrie Ann Davis Dec 2012

Assessing The Impacts Of Surface Water Removal For Use In Natural Gas Extraction On A Watershed Level, Carrie Ann Davis

Graduate Theses and Dissertations

In this study, the Soil and Water Assessment Test (SWAT) was used as a tool to predict whether diffuse water removal from the Cadron Creek watershed for use with natural gas development would have an impact on downstream flow within the watershed. Cadron Creek watershed expands across four counties within Arkansas and is located in the Fayetteville Shale Gas region. This region is experiencing significant growth in natural gas development. Successful development of shale gas depends on the identification of what water supplies are available for production without interfering with community and environmental needs. The SWAT model used to evaluate …


A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh Dec 2012

A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh

Graduate Theses and Dissertations

This study compares a novel simulation approach to the conventional Soil and Water Assessment Tool (SWAT) modeler's approach for targeting biofuel crop production on marginal lands. In conventional SWAT modeling approach, non-spatial definition of hydrological response units (HRUs) results in the simulation of biofuel crops on both marginal and non-marginal land. This study provides an alternative approach in which a marginal-land raster was integrated into the land use and land cover (LULC) raster in such a way that the land uses were divided into marginal and non-marginal components. This modified LULC was used for model setup which resulted in marginal …


Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello Dec 2012

Diagenesis And Reservoir Characterization Of The Pennsylvanian Middle Atoka Formation, Sebastian And Logan Counties, West-Central Arkansas, Elvis Chekwube Bello

Graduate Theses and Dissertations

The Middle Atoka Formation evolved from a stable passive margin during the early Pennsylvanian time to a rapidly subsiding basin, with the sedimentary fill thickening greatly southward during the middle Pennsylvanian time. The basin dips in north-south direction. An east-west anticlines and synclines were observed.

The purpose of this study is to establish the stratigraphic units, reservoir geometry and distribution, and infer the depositional environments and reservoir quality. Well correlation and petrographic studies are used to achieve the goals.

Sandstone Point Count method was used. The Point Counts was divided into five categories. They include the framework grains (quartz, feldspar, …


Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak Dec 2012

Exploring The Surface Liquid And Lake Regions Of Titan With Laboratory Experimentation And Cassini Spacecraft Data, Felix Casimir Wasiak

Graduate Theses and Dissertations

The surface liquids and lake regions of Titan are studied utilizing three unique techniques, the results of which are reported in this dissertation. The development of a facility to simulate the surface conditions of Titan, and to conduct experiments on samples within that facility, brings an understanding of Titan's surface not possible through observation and modeling alone. The properties of this facility are presented, including conceptual methodology, design, implementation, performance, and experimental results. The facility, the main component of which is a simulation chamber, allows for Titan temperatures of 90 - 94 K and a 1.5 bar N2 atmosphere. The …


Magnitude And Frequency Of Floods For Rural, Unregulated Streams Of Tennessee By L-Moments Method, Hongxiang Yan Aug 2012

Magnitude And Frequency Of Floods For Rural, Unregulated Streams Of Tennessee By L-Moments Method, Hongxiang Yan

Graduate Theses and Dissertations

This study presents a regional frequency analysis of Tennessee using the well-known Bulletin-17B method standardly used in the United States and the relatively new and developing L-Moments methods. Flood frequency characteristics were defined for 416 gaging stations located primarily in rural and lightly developed areas of Tennessee. All the gaging stations have 10 or more years of record through 2006. Using the L-Moments method, the generalized extreme value distribution was identified as the most robust distribution for each of four hydrologic areas. Multiple regression equations were also calculated for estimating the flood frequency of ungaged, unregulated, rural streams in each …


Outcrop Investigation Of The Reeds Spring (Boone, Mississippian) Of The Hindsville Quarry Using Terrestrial Lidar, Terryl Glenn Daniels Aug 2012

Outcrop Investigation Of The Reeds Spring (Boone, Mississippian) Of The Hindsville Quarry Using Terrestrial Lidar, Terryl Glenn Daniels

Graduate Theses and Dissertations

In northern Oklahoma and southern Kansas the Reeds Springs Formation (Boone, Mississippian) is a hydrocarbon exploration objective (Mazullo et al, 2011). The Hindsville quarry located in the northeastern portion of Washington County in Arkansas is the focus of this study. The objective of this study is to characterize the Reeds Spring at the Hindsville Quarry. The use of terrestrial light detecting and ranging(LiDAR) is used to assist in the characterization of the quarry.

The unit architecture within the Hindsville Quarry outlines varying transitional periods that give insight into the deposition of the Reeds Springs Formation. There are comparable formations within …


A Daily Temperature Record For Central Texas, 1896-2011, Matthew Kain Taylor Aug 2012

A Daily Temperature Record For Central Texas, 1896-2011, Matthew Kain Taylor

Graduate Theses and Dissertations

A continuous record of 882,693 daily maximum, minimum, and mean temperature measurements for seven weather stations in central Texas dating from August 1, 1896, to August 31, 2011, were screened and corrected for missing values and inhomogeneities. The resulting data were averaged to create a 115-year unbroken regional record of daily temperature for central Texas. This record indicates warming in daily, seasonal, and annual temperatures. Winter warm temperature extremes have increased over the period of record while warm temperature extremes during the summer months have remained largely unchanged. Summer heat wave days and the length of heat waves have increased …


A Subsurface Stratigraphic Study Of The Middle Atoka, Sebastian County, Arkansas, Sara Beth Sutton Aug 2012

A Subsurface Stratigraphic Study Of The Middle Atoka, Sebastian County, Arkansas, Sara Beth Sutton

Graduate Theses and Dissertations

Raster log images were analyzed to study the subsurface stratigraphy of the Middle Atoka in the Arkoma Basin of the western portion (Sebastian County) of Arkansas. The most significant sandstone units of the Middle Atoka in this area were determined to be two generally coarsening-upward sequences in the lower portion of the formation. Based on lithologic correlations, these two units were determined to be the informally named Casey and Freiburg members of the Middle Atoka. Thickness information based on picked tops was used to create isopach maps of the units of interest. The log signatures and geometry of the sand …


Reservoir Characterization And Outcrop Analog: The Osagean Reeds Spring Formation (Lower Boone), Western Osage And Eastern Kay County, Oklahoma, Taylor Friesenhahn Aug 2012

Reservoir Characterization And Outcrop Analog: The Osagean Reeds Spring Formation (Lower Boone), Western Osage And Eastern Kay County, Oklahoma, Taylor Friesenhahn

Graduate Theses and Dissertations

The Reeds Spring Formation (Osagean) is a member of the Lower Mississippian carbonate series developed on the Cherokee Platform Province of northeastern Oklahoma. On the western flank of the Ozark Dome, these rocks dip in a west-southwest direction into the subsurface where they are oil and gas reservoirs. A series of road cuts and surface exposures are cropped out in the tri-state area of northwest Arkansas, northeastern Oklahoma, and southwestern Missouri. Outcrop characteristics, including an abundant amount of nodular, anastomosing chert, generally finer-grained carbonate texture, and stratigraphic relationships provide an analog for its subsurface counterpart. Based on core description and …


Sequence Stratigraphy And Depositional Systems Of The Mansfield Sand, Upper Atoka Formation, Arkoma Basin, Arkansas, Scott Cherry Aug 2012

Sequence Stratigraphy And Depositional Systems Of The Mansfield Sand, Upper Atoka Formation, Arkoma Basin, Arkansas, Scott Cherry

Graduate Theses and Dissertations

The Mansfield sand is an informally named member of the Pennsylvanian Atoka Formation in Arkansas. Once a productive gas reservoir, the Mansfield is situated in a double plunging anticline in the southern portion of the Arkoma Basin. The formation is internally composed of sandstone units ranging in thickness from tens of feet to over a hundred feet interbedded with shale units ranging in thickness from several tens of feet to hundreds of feet. Previous studies have focused on the stratigraphy of the lower and middle Atoka. A detailed subsurface study of the stratigraphic framework of the Mansfield sand was conducted …


Water Quality Trends And Nutrient Loads For The Watershed Research And Education Center In Northwest Arkansas, 2009-2012, John Metrailer Aug 2012

Water Quality Trends And Nutrient Loads For The Watershed Research And Education Center In Northwest Arkansas, 2009-2012, John Metrailer

Graduate Theses and Dissertations

Nitrogen, phosphorus, and sediment transport is a concern for Northwest Arkansas due to high exports through riverine discharge. Urban, agricultural, and pastured watersheds have been associated with increased N, P, and sediment concentrations when compared to forested catchments. The objective of this study was to evaluate discharge and nutrient loads associated with a small urban, agricultural (row crop), wetland influenced, and pasture/farmland sub-catchment within four ephemeral drainages and located at the Watershed Research and Education Center in Fayetteville, AR. Samples were collected during base flow conditions and periodic storm flow conditions from 2009-2012. Flow adjusted concentration trends were used to …


Groundwater Quality Assessment From Domestic Water Wells In The Fayetteville Shale Gas Play Area In Central Arkansas, Anna Marie Nottmeier Aug 2012

Groundwater Quality Assessment From Domestic Water Wells In The Fayetteville Shale Gas Play Area In Central Arkansas, Anna Marie Nottmeier

Graduate Theses and Dissertations

This study establishes a spatially distributed domestic water well groundwater quality data set, throughout the Fayetteville Shale Gas Play (FSGP) in central Arkansas. The data set facilitates characterization of the geology and groundwater quality across the study area, benefits residents who may have concerns about the potential impacts on their well water quality, and provides a groundwater quality basis to which complaints can be compared and resolved. The assessment included: research of the study area, site reconnaissance, water sampling and collection, interviews with owners of the property, analytical analysis, Quality Assurance and Quality Control, and groundwater data interpretation.

The study …


Subsurface Planetary Investigation Techniques And Their Role For Assessing Subsurface Planetary Composition, Ahmed Elshafie Aug 2012

Subsurface Planetary Investigation Techniques And Their Role For Assessing Subsurface Planetary Composition, Ahmed Elshafie

Graduate Theses and Dissertations

Subsurface planetary investigation techniques are of high interest and importance for the scientific community. Not only they can enhance our knowledge of the history of planetary formation but also can lead to information about its future. Whether the investigation is being conducted remotely using imagers, radars or physically using penetrometers or drills, a pre-existed knowledge of the mechanical and electrical properties of the subsurface regolith should be acquired for better data interpretation and analysis. Therefore, the main objective of this work is to investigate the mechanical and electrical properties of planetary analogs, understand their role for assessing the subsurface structure …


Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life, Dixie Lee Androes Aug 2012

Orbital Periodicities Reflected In Ancient Surfaces Of Our Solar System And The Implications For A Record Of Early Life, Dixie Lee Androes

Graduate Theses and Dissertations

Uniformitarian processes, governed by invariant physical laws, remain the most reliable source for reconstructing the past. Driving many of the repetitive, predictable processes are the orbital dynamics of the Sun-Planet-Moon systems. Astronomical periodicities range from a few hours (tides) to thousands of years (Milankovitch). These periodicities, combined with geomorphic observations of planetary surfaces, constrain the time-dependent processes and allow for reconstruction of events and conditions favorable for sedimentary accumulations. This research suggests that seasonal sedimentary processes are dominant on Titan and Mars, and have played a significant role in the formation of ancient banded-iron formations (BIF's) on Earth.

Earth, Mars, …


Stability Of Phyllosilicates On Mars, Patricia Gavin Aug 2012

Stability Of Phyllosilicates On Mars, Patricia Gavin

Graduate Theses and Dissertations

This study investigates the stability of phyllosilicates on the surface of Mars through laboratory experiments and analysis of terrestrial analogs. Phyllosilicates are mostly found in the oldest Noachian terrains on Mars and hence hold clues to the planet's earliest aqueous and geologic history. Phyllosilicates relevant to Mars were heated up to ~1100°C for up to 24 hours and impacted with projectile velocities up to ~4.5 km/s. Heated samples were analyzed using x-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) spectroscopy in the near- (NIR, 1.0-2.5 µm) and mid-infrared (MIR, 5.0-15.0 µm) ranges. Impacted samples were also analyzed using Raman spectroscopy …


Synergy Of Alum And Chlorine Dioxide For Curbing Disinfection Byproduct Formation Potential At Central Arkansas Water, Corey W. Granderson May 2012

Synergy Of Alum And Chlorine Dioxide For Curbing Disinfection Byproduct Formation Potential At Central Arkansas Water, Corey W. Granderson

Graduate Theses and Dissertations

Central Arkansas Water (CAW), the water utility for Little Rock, AR, draws their source water from Lake Maumelle and Lake Winona. To curb disinfection byproduct (DBP) formation, CAW has begun retrofitting their two plants to use chlorine dioxide as an alternative primary disinfectant followed by free chlorine secondary disinfection in the distribution system. In this study, fluorescence parallel factor (PARAFAC) analysis was combined with free chlorine simulated distribution system (SDS) tests and DBP formation potential (DBPFP) tests to study the benefit of chlorine dioxide primary disinfection (CDPD) with alum coagulation. Of the DBPs screened, trichloromethane (TCM) was formed in highest …


Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo May 2012

Mathematical Modeling Of Fluid Spills In Hydraulically Fractured Well Sites, Oluwafemi Michael Taiwo

Graduate Theses and Dissertations

Improved drilling technology and favorable energy prices have contributed to the rapid pace at which the exploitation of unconventional natural gas is taking place across the United States. As a natural gas well is being drilled, reserve pits are constructed to hold the drilling fluids and other materials returned from the drilling process. These reserve pits can fail, and when they do, plant and animal life of the surrounding area may be adversely affected. This project develops a screening tool for a suitable location for a reserve pit. This work will be a critical piece of the Infrastructure Placement Analysis …


Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser May 2012

Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser

Graduate Theses and Dissertations

This project combines geoarchaeological soil description and GIS analysis of archaeological site distribution to investigate the history of marsh formation in the northern Ghab Basin, located within the Orontes River Valley of western Syria. Tell Qarqur, the archaeological site around which this project is focused, has a continuous occupational sequence throughout the Holocene. Annual inundation of the site by seasonal marshlands suggests that the marsh was either smaller or non-existent in the past, but its history remains unknown. The objectives of this investigation are to interpret the nature of depositional environments, particularly fluvial action, in the vicinity of Tell Qarqur, …


Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan May 2012

Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan

Graduate Theses and Dissertations

Slope failure continues to pose risks to society because knowledge of environmental factors and their interactions are unclear and possibly misunderstood. This misunderstanding leads to generalizations about slope failure susceptibility mapping, despite knowing that slope failures are likely the result of an extensively complex set of interactions among a number of environmental, edaphic, and geomorphic characteristics. Therefore a series of experiments were conducted to investigate the effects of slope, soil texture, vegetation cover, bedrock permeability, and compaction,. A wooden flume with a slope face 1 m wide by 1.5 m long with a 10 cm toe was constructed to contain …


Identifying Optimal Cellulosic Biomass Feedstock Supply Areas For Potential Biorefineries In Arkansas, Mark Cooper May 2012

Identifying Optimal Cellulosic Biomass Feedstock Supply Areas For Potential Biorefineries In Arkansas, Mark Cooper

Graduate Theses and Dissertations

In February 2010, the U.S. Environmental Protection Agency released the revised Renewable Fuel Standard (RFS2), mandating at least 36 billion gallons of renewable fuels to be produced annually in America, and blended into all on/off road, locomotive, and marine gasoline and diesel by the year 2022. America's existing biorefineries fall significantly short of being able to meet this mandate, resulting in the need for rapid expansion in the near future if this goal is to be met. The state of Arkansas has abundant resources to offer the renewable energy industry, if properly utilized. The goal of this thesis is to …


Data Integration And Reservoir Characterization Of The Pennsylvanian Bartlesville Sandstone, Caroline Vance O'Keefe May 2012

Data Integration And Reservoir Characterization Of The Pennsylvanian Bartlesville Sandstone, Caroline Vance O'Keefe

Graduate Theses and Dissertations

The Glenn Pool Oil Field of Northeastern Oklahoma was established as the first major oil discovery of the fledgling state of Oklahoma. Fully developed by 1912, the field is now nearing depletion even under secondary and tertiary recovery efforts after production for approximately 100 years. Large amounts of residual oil estimated to still be in place have motivated exploration into other recovery methods, including polymer flooding and horizontal drilling. Success of these programs is dependent upon accurate characterization of the reservoir. Because most of the drilling occurred many decades ago, much of the data associated with this field predates electric …


Modeling Water Stability And Transport On Mars And Iapetus: Exploring Their Effects On Geomorphic And Atmospheric Processes, Edgard Giovanni Rivera-Valentin May 2012

Modeling Water Stability And Transport On Mars And Iapetus: Exploring Their Effects On Geomorphic And Atmospheric Processes, Edgard Giovanni Rivera-Valentin

Graduate Theses and Dissertations

The stability and transport of water on solid planetary surfaces strongly affects both atmospheric and surfaces processes. In this work, two bodies are specifically investigated where transport of water is relevant: Iapetus and Mars. Iapetus, an icy Kronian satellite, has a drastic albedo contrast on its surface and one of the darkest surfaces in the solar system. This extreme brightness contrast is suggested to occur via the transport of water ice from the leading hemisphere to the trailing hemisphere and the poles. Here a global heat and mass transfer model is developed for Iapetus in order to study the current …


Impacts Of Hard Stabilization On The Shore Of Yellowstone Lake, Yellowstone National Park, Wyoming, Usa, John Chandler Dennis May 2012

Impacts Of Hard Stabilization On The Shore Of Yellowstone Lake, Yellowstone National Park, Wyoming, Usa, John Chandler Dennis

Graduate Theses and Dissertations

Discussions related to the adverse impacts associated with shore armor (i.e. seawalls and riprap) are a common topic within the coastal community. While many agree that the installation of these structures alters the shores geomorphic response, there is disagreement in the type and degree of response. Furthermore, studies that have delved into this topic have been conducted in numerous settings but have been confounded by a lack of data regarding shore morphologies prior to installation of these structures. At Yellowstone National Park, there is an opportunity to assess the impacts of shore armor quantitatively because the National Park Service requires …


Integrating Human Variables In Cross-Boundary Monitoring Of Aberdare Preserves In Kenya, Peter K. Njuguna May 2012

Integrating Human Variables In Cross-Boundary Monitoring Of Aberdare Preserves In Kenya, Peter K. Njuguna

Graduate Theses and Dissertations

This research critically examines extant data systems and their linkage of scientific research to policy and public education in east African highland forest conservation preserves. The research indicates that the current state of data and monitoring systems in the region imposes substantial limitations on the ability to manage these preserves. Major outcomes of those constraints manifest in unprecedented cross-boundary pressure such as encroachment and conversion of forest to agriculture, increased human-wildlife conflicts, and constrained relations among primary stakeholders. Current monitoring is biodiversity focused within preserves and fails to capture human dimensions in adjoining areas across preserve boundaries. This study proposes …


Stratigraphy And Provenance Of Shallow Sandstones Endountered In Wells In Townships 9 And 10 North, Ranges 6 And 7 West, White County, Arkansas, Lacie Knight May 2012

Stratigraphy And Provenance Of Shallow Sandstones Endountered In Wells In Townships 9 And 10 North, Ranges 6 And 7 West, White County, Arkansas, Lacie Knight

Graduate Theses and Dissertations

Paleozoic formations in western Arkansas have been well-studied; however, they are not well-understood in the eastern part of the state. The study area encompasses Townships 9. N. and 10. N., Ranges 6. W. and 7. W. in north-central White County, Arkansas. This area is at the intersection of four physiographic provinces as defined by the Arkansas Geologic Survey- the Ozark Plateaus, the Arkansas River Valley, the Ouachita Mountains, and the Mississippi Alluvial Plain. Interpretations of the surface unit in the area disagree. The Arkansas Geologic Map shows that the Morrowan Hale Formation crops out in the area; however, various petroleum …


The Use Of Diatoms To Infer Environmental Change Of The Lower White River, Southeastern Arkansas, Ruchi Bhattacharya May 2012

The Use Of Diatoms To Infer Environmental Change Of The Lower White River, Southeastern Arkansas, Ruchi Bhattacharya

Graduate Theses and Dissertations

This dissertation describes the limnology of the lower White River oxbow lakes in southeast Arkansas, inundated by the major 2008 spring flood. The flood water and sediment deposited in oxbow lakes were analyzed for water chemistry, sediment geochemistry and diatom assemblages and used as an analogue for past floods. The 2008 spring flood inundated and homogenized the entire floodplain; also represented by the predominantly planktonic diatom assemblage suggesting riverine input. Indicator species for eutrophication were also recorded consistent with the high nutrient content in the lakes. However, the variance in the surface diatom assemblage was best explained by the lake …


Experimental Simulations Of Dark Slope Streaks On Mars, Kelly Howe May 2012

Experimental Simulations Of Dark Slope Streaks On Mars, Kelly Howe

Graduate Theses and Dissertations

Martian slope streaks were first observed in Viking images but their formation still remains ambiguous. Martian slope streaks are currently occurring geological phenomenon on Mars, which requires any formation theory to be in agreement with Mar's current temperature and pressure conditions. Planar morphology of martian slope streaks suggest a potential fluvial formation, but current conditions on Mars are not conducive to water remaining liquid long enough to erode the surface. Debris flows, fluid stains and dry dust avalanches have all been previously cited as a potential formation mechanism for martian slope streaks. Recent experimental simulations indicate that a fluvial source …