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Full-Text Articles in Physical Sciences and Mathematics

A Morphometric Analysis Of The Highly Variable Clypeasteroid, Periarchus Lyelli, Lauren Elizabeth Williamson Jan 2009

A Morphometric Analysis Of The Highly Variable Clypeasteroid, Periarchus Lyelli, Lauren Elizabeth Williamson

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The Late Eocene echinoid, Periarchus lyelli (Conrad, 1834), known for its wide geographic range, high abundance, and specific stratigraphic range, is an ideal example of a guide fossil. However, due to its highly variable test morphology, many have questioned if, in fact, this sand dollar is actually two or three distinct species that have been misclassified. A preliminary study on this subject has been performed on specimens from Mississippi, North Carolina and South Carolina (Williamson, 2006), showing significant separation in test shapes. Continuing previous research, this study analyzes the test shapes of P. lyelli over its entire North American geographic …


Bench-Scale Conversion Of Carbon Dioxide To A Hydrocarbon Fuel, Melissa L. Kennedy Jan 2009

Bench-Scale Conversion Of Carbon Dioxide To A Hydrocarbon Fuel, Melissa L. Kennedy

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There is a growing concern about the effects of global warming that many believe is anthropogenically caused. As such, scientists are trying to uncover a viable alternative fuel source and establish a way to reduce atmospheric carbon dioxide levels. A potential solution that addresses both of these aspects would be to capture atmospheric carbon dioxide and convert it into a natural gas, in particular methane, which could be used as an energy source. A laboratory-scale experiment using 6 160 mL microcosms (3 with anaerobic wetland soil and 3 relatively soil free) and 2 7.2 L bioreactors was conducted to learn …


Hydrogeochemistry And Water Quality Of Echo Hills, Joel M. Kimball Jan 2008

Hydrogeochemistry And Water Quality Of Echo Hills, Joel M. Kimball

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Ground water of the Echo Hills area in Clark County, Ohio was investigated for common water contaminants such as nitrate and coliform bacteria. Thirty-four water samples were collected from locations including private wells, streams and a spring. Nine of those samples were selected for nitrogen isotope analysis. Three locations were chosen for a tracer test. Additionally, well log data, historical water quality data, and GIS data were obtained from the Clark County Health Department in Springfield, Ohio. Results show that local agriculture likely has the greatest impact on ground water quality in Echo Hills especially the north-eastern portion, with local …


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

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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 …


Preliminary Results From A Holocene Record From Crystal Lake, Southwestern Ohio, Rebecca Teed, Leigh Deuter, Ashley Kesler, Graham Parker, Melissa Sparks Jan 2008

Preliminary Results From A Holocene Record From Crystal Lake, Southwestern Ohio, Rebecca Teed, Leigh Deuter, Ashley Kesler, Graham Parker, Melissa Sparks

Earth and Environmental Sciences Faculty Publications

No abstract provided.


Geologic Mapping Of The Changgo Dome In Southern Tibet Using Aster Imagery, Andrew Paul Folfas Jan 2008

Geologic Mapping Of The Changgo Dome In Southern Tibet Using Aster Imagery, Andrew Paul Folfas

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Within the thick TSS, south of the Indus-Tsangpo Suture, a series of granitic intrusions and gneissic domes crop out along the NHA. These culminations are common features that are seen in orogenic belts; therefore, understanding the nature and development of these features is an integral part of this study and other collisional orogenic studies. Changgo Dome is a granitic dominated feature that is characterized by the presence of two spectrally similar Tertiary granites. This zone is nearly inaccessible for ground mapping, thus it is an ideal setting for the use of satellite imagery as a cartographic medium. In a previous …


Availability And Toxicity Of Nickel To Lotic Periphyton And Macroinvertebrates, Stephanie Marie Bessom Jan 2008

Availability And Toxicity Of Nickel To Lotic Periphyton And Macroinvertebrates, Stephanie Marie Bessom

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There is a lack of information regarding the bioaccumulation and toxicity of nickel (Ni) to lotic ecosystems. The objective of this study was to investigate the source, uptake, and toxicity of Ni by periphyton and macroinvertebrates (Hyalella azteca and Daphnia magna) in simulated stream ecosystems that included sediment and water. Periphyton were exposed to two types of sediment, a low-organic sandy mixture and a high organic silt, treated with varying levels of Ni. After 96 h, Ni levels in overlying water and periphyton were related to those in sediments, although differences existed between sediment types. Tests with 64Ni added to …


Analysis And Interpretation Of 2d Seismic Data Over The Ancona Gas Storage Facility, Illinois, Using Petrel Visualization Software, Nilanjan Roy Jan 2008

Analysis And Interpretation Of 2d Seismic Data Over The Ancona Gas Storage Facility, Illinois, Using Petrel Visualization Software, Nilanjan Roy

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Intriguing features of the North American mid-continent are the widespread and prominent subhorizontal seismic reflectors that are thought to be associated with thick sequences of layered rocks beneath the Phanerozoic cover of the Illinois Basin. The present investigation was an effort to identify and interpret new structural features of the pre-Paleozoic crust at the Ancona Gas Storage field in north-central Illinois. A grid of existing seismic data was reprocessed using the technique of extended correlation.

The reprocessed data was then analyzed using Schlumberger's Petrel visualization software for seismic interpretation and reconstruction of the 2D and 3D crustal geometry. The reprocessing …


Investigating Nickel Flux And Toxicity In Clay Sediments With Batch And Stream Recirculating Flume Experiments, Christina Elizabeth Cloran Jan 2008

Investigating Nickel Flux And Toxicity In Clay Sediments With Batch And Stream Recirculating Flume Experiments, Christina Elizabeth Cloran

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Using batch and stream recirculating flume experiments to compare and contrast one clayey sediment (Warden Ditch) and two analytical grade clay minerals (montmorillonite and kaolinite), the dynamic interactions between two aquatic stressors (suspended solids and nickel) were explored. Aldrich humic acid was incorporated to demonstrate the mitigating effects of dissolved organic carbon (DOC) on Ni toxicity. The flux of Ni between compartments (dissolved and sorbed) was quantified as a partition/distribution coefficient. The USEPA test organism Daphnia magna (neonates, < 24 h) was utilized to evaluate toxicity in dynamic non-renewal, short-term bioassays. Generally, toxicity showed a linear relationship with turbidity level. Conversely, sorption coefficients were experiment specific, making them difficult to predict and assess. Clay functioned as an adsorbent, scavenging Ni. Results support the hypotheses that solids and metals act as stressors in streams, DOC attenuates the toxicity of Ni, and Ni fluxes quickly between system compartments.


Geological Mapping Of Orhon, Tariat, And Egiin Dawaa, Central Mongolia, Through The Interpretation Of Remote Sensing Data, Tara Alexandra Stolz Jan 2008

Geological Mapping Of Orhon, Tariat, And Egiin Dawaa, Central Mongolia, Through The Interpretation Of Remote Sensing Data, Tara Alexandra Stolz

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Multi-spectral satellite data from the Advanced Spaceborn Thermal Emission and Reflection Radiometer (ASTER) and Landsat Thematic Mapper (TM) were used to make interpretations regarding the surface lithology and structure of the Tariat, Egiin Dawaa, and Orhon regions in Central Mongolia. These areas experienced widespread Cenozoic volcanism. This study mapped the locations and extents of the volcanic flows, located cinder cones and faults evident in the areas, and identified a possible exposure of the Mongolian granitic batholith in the Orhon area. ER Mapper, a geospatial imaging software, was used to generate and run algorithms. Image transforms and supervised classifications were used …


Degradation Of Chlorinated Ethenes In Mesocosms Simulating A Constructed Wetland, At Wpafb, Ohio, Dibyendu Mukherjee Jan 2008

Degradation Of Chlorinated Ethenes In Mesocosms Simulating A Constructed Wetland, At Wpafb, Ohio, Dibyendu Mukherjee

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The main purpose of this research was to study the degradation of chlorinated ethenes in upwardflowing mesocosms, simulating a constructed wetland at Wright Patterson Air Force Base (WPAFB) in Dayton, Ohio. This research was intended to compare biogeochemical processes and PCE degradation occurring in the mesocosms and in the field site. This research also tries to look at the effects of vegetation and season on the degradation efficiency of the mesocosms. Twelve PVC column reactors were built within the greenhouse of Wright State University in September 2005 to simulate the hydraulic conditions of a constructed wetland at WPAFB. The columns …


Estimation Of Evapotranspiration Of Cottonwood Trees In The Cibola National Wildlife Refuge, Cibola, Arizona, Amity J. Jetton Jan 2008

Estimation Of Evapotranspiration Of Cottonwood Trees In The Cibola National Wildlife Refuge, Cibola, Arizona, Amity J. Jetton

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This study used sap flow measurements and satellite imagery to estimatewater use by cottonwood (Populus fremontii S. Wats. ssp) trees in an irrigated restoration plot at Cibola National Wildlife Refuge on the Lower Colorado River. Several thousand hectares of irrigated plots of this type are planned to improve riparian habitat on the river, hence it is important to know how much water the trees require. In this study, the ET rates for 20 Freemont cottonwood trees, from an 8 ha plot, were monitored over a 30-day period. ET rates were estimated by measuring sap flow through branches of the trees. …


The Impact Of Nutrient Availability And Algal Community On Carbon Isotope Fractionaion In Crystal Lake, Clark County, Ohio, April R. Wisebaker Jan 2008

The Impact Of Nutrient Availability And Algal Community On Carbon Isotope Fractionaion In Crystal Lake, Clark County, Ohio, April R. Wisebaker

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Crystal Lakes are a group of four interconnected lakes, located in southwestern Clark County, Ohio. Several studies have looked at separate geochemical and isotopic information at this location. However, no one has thoroughly studied the relationship between the algal community, geochemistry, and carbon isotope fractionation within Crystal Lake. The fractionation of carbon isotopes of dissolved inorganic carbonate is greatly affected by the process of photosynthesis; the amount of photosynthesis is affected by the amount of algae in the aquatic community; the amount of algae is affected by the available nutrients in system. Therefore, there should be a correlation between the …


Paleoenvironment And Lateral Extent Of An Exposed Carbonate Build-Up: Horry County, South Carolina, Lisa A. Raterink Jan 2008

Paleoenvironment And Lateral Extent Of An Exposed Carbonate Build-Up: Horry County, South Carolina, Lisa A. Raterink

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A carbonate build-up exposed in the Intracoastal Waterway in Horry County, South Carolina is estimated to be Pleistocene to Pliocene in age. The carbonate build-up discontinuously spans approximately 12 kilometers of the waterway. Prominent formations in the area consist of the Waccamaw and the Canepatch Formation. A distinct sand layer is present laterally between the build-up and the excavated waterway bank, which consists primarily of well preserved fossil molluscs and echinoderms.

Field observations show that the carbonate build-up is bluish-gray in color and composed of shell fragments, predominantly mollusc, in a mud matrix. Thin sections analyzed, using a petrographic microscope, …


Seasonal Variation In The Redox Zones And Biogeochemical Processes Within The Constructed Wetland, Yussuf Mohamud Jan 2007

Seasonal Variation In The Redox Zones And Biogeochemical Processes Within The Constructed Wetland, Yussuf Mohamud

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This research investigation focuses on the vertical distribution of dissolved inorganic species in the pore-water affected by redox processes and seasonal changes within a small constructed wetland located at the Wright-Patterson Air Force Base. This is a follow up study to an earlier investigation (Lach, 2004) at this site in 2003. Water samples were collected from influent, effluent and three layers of the constructed wetland through a network of nested piezometers in the vertical flow wetland from June 2005 to June 2006. Onsite analysis of temperature, pH and conductivity were carried out onsite. Major anions and cations were measured by …


Evidence Of A Pre-Mount Simon, Half-Graben In Greene County, Ohio By Reprocessing A Wright State University Seismic Line, John Sink Jan 2007

Evidence Of A Pre-Mount Simon, Half-Graben In Greene County, Ohio By Reprocessing A Wright State University Seismic Line, John Sink

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The reprocessing of the WSU2002 seismic line indicates the presence of a Precambrian half-graben. Also observed through this reprocessing is the possible presence of Paleozoic structures. Although Paleozoic features have been interpreted, variations in glacial drift thickness evidenced by glacial drift maps also may have contributed to a lower quality of stacked section in comparison to other seismic lines. WSU2002 was originally processed by Lauren Geophysical. The Lauren processing resulted in an image that was of much lower quality than corresponding seismic lines. The Lauren Geophysical processed section revealed many horizontal Paleozoic reflections, with no prominent reflectors beneath the Paleozoic. …


Geophysical Reconnaissance Of Karst Features Associated With Sinkholes On The Antioch University Campus In Yellow Springs, Ohio: Western Area, Brent Matthew Zerkel Jan 2007

Geophysical Reconnaissance Of Karst Features Associated With Sinkholes On The Antioch University Campus In Yellow Springs, Ohio: Western Area, Brent Matthew Zerkel

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Antioch University is located in Yellow Springs, OH. This study was conducted on the Antioch University Campus in the commons area and is concentrated on the area west of the easternmost sinkhole. The primary purpose of this study is to locate and identify buried anomalous karst features, such as joints and collapses that may be hazardous to nearby buildings on the Antioch University Campus. The secondary purposes of this study are to identify remaining features in the geophysical data that may be related to manmade structures, and to identify areas for future studies. It is known that an 8-inch steel …


Porosity And Permeability Of Bimodal Sediment Mixtures Using Natural Sediment, Peter M. Phillips Jan 2007

Porosity And Permeability Of Bimodal Sediment Mixtures Using Natural Sediment, Peter M. Phillips

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Porosity and permeability are parameters that affect the flow of ground water in the subsurface and have significant implications on the modeling of fate and transport of contaminants. However, little has been done to quantitatively examine the effect on porosity and permeability of packing in bimodal mixtures of natural sediment. This study compares measurements of porosity and permeability on model bimodal sediment mixtures with predictions from petrophysical models. The main goal is to evaluate how well these petrophysical models predict porosity and permeability in bimodal mixtures of natural sediment. The effect of the volume fraction of fines on porosity and …


Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke Jan 2007

Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke

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Geology and land use and land cover are the most important factors that influence water quality. The purpose of this study is to investigate how these factors operate in a rural watershed. Specifically, this thesis tests the feasibility of a proposed formula to relate how land use affects surface water quality and to infer hydrogeochemical reactions that control water chemistry through hydrogeochemical speciation and mineral stability relationships. Samples were collected from Indian Lake and its watershed in West-Central Ohio. BASINS, produced by the USEPA, was then used to delineate sub-watersheds and find the land use areas of these watersheds. The …


Biogeochemical Processes And Seasonal Effects In Flow-Through Mesocosm Reactors Simulating Constructed Wetlands, Sarah J. Tritschler Jan 2007

Biogeochemical Processes And Seasonal Effects In Flow-Through Mesocosm Reactors Simulating Constructed Wetlands, Sarah J. Tritschler

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Due to their distinctive environments, constructed wetlands are utilized to remediate groundwater that has been contaminated with chlorinated ethenes (i.e. perchloroethene) and other such contaminants. This research focuses on vertical flow mesocosm reactors housed in a greenhouse at Wright State University, which simulate a constructed wetland on Wright-Patterson Air Force Base. These reactors were studied to investigate the effects of vegetation and seasonal changes on the redox parameters present. Water samples were collected from six different reactors from late September/early October 2006 until August 2007. The reactors were sampled three days in a row and this sampling was done once …


Feasibility Analysis Of The Strontium Ratio Obtained From Pennsylvanian Chondricthian Dentary, Cullen John Erbacher Jan 2006

Feasibility Analysis Of The Strontium Ratio Obtained From Pennsylvanian Chondricthian Dentary, Cullen John Erbacher

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This research was undertaken to determine the amount of time between transgressive and regressive sequences. One of the methods used to determine the amount of missing time in an unconformity is the 87Sr / 86Sr ratio. The 87Sr / 86Sr ratio will be high around brackish and freshwater environments while it will be lower in open marine conditions. Limestones and their constituent parts are susceptible to diagenetic processes that can contaminate or obliterate isotope values contained within the rocks. The purpose of this research was to discover if reliable isotope information could be pulled from Pennsylvanian aged shark teeth. Nine …


Characterization And Interpretation Of The Cephalopod Marker Bed, Oakes Quarry Park, Fairborn, Ohio, Jessica Nicole Mcdonough Jan 2006

Characterization And Interpretation Of The Cephalopod Marker Bed, Oakes Quarry Park, Fairborn, Ohio, Jessica Nicole Mcdonough

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A distinct sequence of orange-brown, fossiliferous grainstones with interbedded blue mudstones exists in the upper portion of the Silurian-aged (Llandoverian) Brassfield Formation exposure at Oakes Quarry Park, Fairborn, Ohio. The unit is locally referred to as the cephalopod marker bed as it can be easily identified and is continuous throughout the quarry. The unit varies considerably in thickness (0.3m-0.9m) and contains a variety of sedimentary structures and fossils indicative of a warm, shallow marine environment subject to wave action. Dominant fossils within the unit include echinoderms, cephalopods, bryozoans, abraded mollusks, gastropods, brachiopods, and trilobites. Less-common fossil organisms within the unit …


Geostatistical Characterization Of Heterogeneity In The Aberjona River Aquifer, Woburn, Massachusetts, James Ralph Damico Jan 2006

Geostatistical Characterization Of Heterogeneity In The Aberjona River Aquifer, Woburn, Massachusetts, James Ralph Damico

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Ground water flow and contaminant transport patterns are largely controlled by the distribution of high- and low-permeability sediments. Therefore, an accurate description of the aquifer architecture is paramount to producing a representative ground water model. Models of contaminant fate and transport in the aquifer near Woburn, Massachusetts, have previously been created by others using a deterministic approach. As a complement to these prior studies, the proportions, geometry, and juxtaposition of the different lithofacies of the aquifer were statistically characterized for developing stochastic models for the aquifer system. The descriptions of lithology from boreholes were separated into eleven categories based primarily …


A Student-Centered Project For Earth System History, Rebecca Teed Jan 2005

A Student-Centered Project For Earth System History, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This project is intended to replace some of the lectures that would ordinarily be necessary in a survey of Earth history over geologic time. The students will be taking the lecturer's place in front of the class, presenting some of the material to their colleagues. Students will work in groups on a single era or period. Each student role-plays an expert (such as an oceanographer) and works with teammates playing other sorts of experts (a biologist, a geologist, an atmospheric scientist). Their presentation will require them to do research. They will be constructing resource lists to keep track of how …


Identification Of Gypsy Moth Defoliation In Ohio Using Landsat Data, Angela Lorraine Hurley Jan 2003

Identification Of Gypsy Moth Defoliation In Ohio Using Landsat Data, Angela Lorraine Hurley

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The gypsy moth is one of the most devastating forest pests in North America. In late spring, gypsy moth larvae hatch from eggs laid the previous summer. During the next forty days, tens of thousands of these caterpillars eat up to one square foot of foliage each. The gypsy moth has established populations in several states, and dangerously fast-growing populations in several others. The state of Ohio is a critical area in the suppression of the gypsy moth because the front of gypsy moth advance passes through the state. Besides diminishing the aesthetic value of Ohio’s forests, gypsy moths also …


A >130,000-Year-Long Pollen Record From Pittsburg Basin, Illinois, Rebecca Teed Sep 2000

A >130,000-Year-Long Pollen Record From Pittsburg Basin, Illinois, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

Pittsburg Basin, in south-central Illinois, contains a sediment record extending from the present back to the end of the late Illinoian glaciation, when central Illinois was covered with Picea/Pinus forest. During the last interglaciation, a temperate deciduous forest more diverse than Holocene Quercus/Carya forest replaced the Illinoian late-glacial boreal forest. Prairie pollen types and the charcoal/pollen ratio, indicating fire frequency, temporarily increased. Then forest, with high Juniperus percentages, became dominant once more, as the charcoal/pollen ratio dropped. After the last interglaciation, the charcoal/pollen ratio increased again and prairie and wetland surrounded Pittsburg Basin through the entire Wisconsinan glacial age. The …


Interaction Of A Group Of Dislocations Within The Framework Of The Continuum Frenkel-Kontorova Model, Naum I. Gershenzon Nov 1994

Interaction Of A Group Of Dislocations Within The Framework Of The Continuum Frenkel-Kontorova Model, Naum I. Gershenzon

Physics Faculty Publications

The Frenkel-Kontorova (FK) model of edge dislocation is analyzed. Solutions of the continuum limit of the FK model [the sine-Gordon (SG) equation] are obtained in a form convenient for investigation of dynamics of a large number of interacting dislocations. We consider, based on these solutions, some nonstationary processes: dislocation generation, diffusion of dislocations, and crack-dislocation interaction. Simple relations connecting the velocity of plastic deformation, density and velocity of dislocations, and the force of interaction between dislocations are obtained. The nucleation of dislocations at a moving crack tip is described.