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Early Permian Seawater From The Delta18o Record Of Fossil Bivalves: Seasonality And A Latitudinal Gradient, James Andrew Beard

Earth & Environmental Sciences - Theses

The transition from a glaciated world to one that was ice-free makes the early Permian a time interval that in many ways mirrors the present, and hence there is great interest in constraining paleoclimate conditions over that transition. A common method for estimating ancient temperatures uses the oxygen isotope composition of marine carbonate, but this approach becomes significantly more complicated prior to the Cretaceous due to uncertainties about diagenesis and the isotopic composition of seawater, which has been hypothesized to be more depleted than during the Cenozoic. I use stable isotope compositions of sequentially microsampled accretionary calcite from fossil bivalves …

Glacial Shortcut Of Arctic Sea-Ice Transport, Michael Stärz, Xun Gong, Rüdiger Stein, Dennis A. Darby, Frank Kauker, Gerrit Lohmann

OES Faculty Publications

Due to the lack of data, the extent, thickness and drift patterns of sea ice and icebergs in the glacial Arctic remains poorly constrained. Earlier studies are contradictory proposing either a cessation of the marine cryosphere or an ice drift system operating like present-day. Here we examine the marine Arctic cryosphere during the Last Glacial Maximum (LGM) using a high-resolution, regional ocean-sea ice model. Whereas modern sea ice in the western Arctic Basin can circulate in the Beaufort Gyre for decades, our model studies present an extreme shortcut of glacial ice drift. In more detail, our results show a clockwise …

Evaluation Of The Effects Of Absorption Field Product Architecture Type On Effluent Dispersal And Soil Chemical Properties In A Profile-Limited Soil, Nina J.M. Prater

Graduate Theses and Dissertations

On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. The traditional absorption field product used in OWTSs is a pipe-and-gravel architecture type, which has been used for decades and is the basis for most design regulations. However, new products of differing architecture types including chambers, polystyrene-aggregate, pipe-and-tire-chip, and gravel-less-pipe systems have recently become available. A three-year field study was conducted in Bethel Heights, AR to assess the performance of several newer products and to compare different architecture types to the traditional pipe-and-gravel …

Interactions Of Zoo Plankton And Phytoplankton With Cyanobacteria, Rebecca J. Alexander

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

Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …

Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander

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

Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …

Assessing Eolian Dust Inputs To Soils In Dry Creek Experimental Watershed, Sw Idaho, Brian Jameson Stark

Boise State University Theses and Dissertations

A geochemical investigation of upland soils in the Dry Creek Experimental Watershed (DCEW) near Boise, Idaho was conducted to assess the potential contributions of eolian dust. Major and trace element compositions of soils within the watershed, loess deposits in the adjacent Western Snake River Plain (WSRP), and underlying granodiorite bedrock were evaluated. Multiple lines of evidence suggest a significant contribution of dust in the soils. Plots of Co/Ti, V/Ti and Cr/Ti indicate that the loess and bedrock occupy distinctly different compositional spaces and that the soils are of intermediate composition, suggesting that the soils are a mixture of the loess …

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …

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 …

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 …

Characterizing The Internal Architecture Of Upper Bone Spring Limestone Turbidites And Mass-Transport Deposits (Mtds) Utilizing High-Resolution Image Log Technology, Jason J. Asmus

Masters Theses

Characterization of reservoir scale (less than 1 meter thick) turbidites and mass-transport deposits (MTDs) using conventional subsurface data is complex, due to millimeter-centimeter scale architectural heterogeneity exhibited by these deposits.

Limited studies of the Bone Spring carbonate turbidites and MTDs within the Delaware Basin subsurface emphasized the use of conventional wire-line log and seismic data to evaluate reservoir potential of such strata. As a result, limited resolution offered by these data sets do not allow for accurate characterization of reservoir, and sub-reservoir scale, architectural and compositional variations.

The present investigation integrates high-resolution (centimeter scale) electrical borehole image logs with conventional …

Penetration Forces For Subsurface Regolith Probes, Ahmed Elshafie

Graduate Theses and Dissertations

Investigating planetary bodies using penetrometers can provide detailed information about its history and evolution. An estimation of subsurface density and porosity can be made from the shape of the penetration curve. Using penetrometers mounted on planetary platforms could be challenging due to the uncertainty of the subsurface composition and since the maximum allowed force for penetration is the weight of the lander or rover on the surface. Estimation of penetration forces can provide a reliable constraint on the maximum reachable depth without endangering the whole mission. Therefore, knowledge of the required penetration force to specific depths can be helpful in …

Geochemical Constraints On Groundwater Recharge In The Royal Slope Area, Grant County, Washington, Zoe Danielle Weis

All Master's Theses

Groundwater, the primary source for potable water in the Columbia Plateau, has experienced significant declines over the past 25 years. Groundwater geochemistry and multivariable statistics were employed to identify and characterize the hydrofacies present, constrain recharge sources, and assess mixing of groundwater in the Royal Slope area of the Columbia Plateau. Geochemical analyses for major ions, stable isotopes, and radiogenic isotopes (14C and tritium) for age dating were performed on groundwater samples collected in 2010 from 24 wells in the study area. The results confirmed that the groundwater evolution in the study area follows the typical Columbia River Basalt Group …

Autumn Migration Of Mississippi Flyway Mallards As Determined By Satellite Telemetry, David George G. Krementz, Kwasi Asante, Luke W. Naylor

United States Geological Survey: Staff Publications

We used satellite telemetry to study autumn migration timing, routes, stopover duration, and final destinations of mallards Anas platyrhynchos captured the previous spring in Arkansas from 2004 to 2007. Of those mallards that still had functioning transmitters on September 15 (n = 55), the average date when autumn migration began was October 23 (SE = 2.62 d; range = September 17–December 7). For those mallards that stopped for .1 d during migration, the average stopover length was 15.4 d (SE = 1.47 d). Ten mallards migrated nonstop to wintering sites. The eastern Dakotas were a heavily utilized stopover area. The …

The Impact Of Creosote Bush (Larrea Tridentata) And Biological Soil Crust On Ca Distribution In Arid Soils Of The Mojave Desert, Brittany Myers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ca is an important nutrient that plays a role in membrane stability and cell repair in plant life. This study examines the impact of creosote bush (Larrea tridentata) and biological soil crust on calcium cycling and distribution in desert soils in order to explore the use of Ca as a biosignature. Samples of creosote bush, biological soil crust and eolian dust were taken at two field sites in the Mojave Desert. The first site is located in Eldorado Valley, NV, a soil formed on a young (800-1200 years) alluvial fan deposit; the second site is located on a late Holocene-aged …

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, …

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 …

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …

Variability Of Pennsylvanian-Permian Carbonate Associations And Implications For Nw Pangea Palaeogeography, East-Central British Columbia, Canada, K. D. Zubin-Stathopoulos, B. Beauchamp, V. I. Davydov, C. M. Henderson

Geosciences Faculty Publications and Presentations

Different stages of Pennsylvanian-Permian carbonate sedimentation in east-central British Columbia record a complex history of changing environments influenced by evolving palaeogeography and climate. Newly recognized tectonically controlled features affected the distribution and variability of carbonate associations, providing new interpretations for this portion of the west coast of Pangea. Both a heterozoan (cool water) and photozoan (warm-water) association were identified on either side of a palaeogeographic high here informally termed “Tipinahokan Peninsula”. Cool water carbonates were located outboard, or to the west of this high, an area influenced by upwelling waters. Inboard of this high, a warm, protected sea developed, here …

Sigma Gamma Epsilon Undergraduate Research Poster Session, Erika Elswick

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Sigma Gamma Epsilon undergraduate research poster session will highlight recent and on-going student research. Abstracts for poster presentations will be available in the Geological Society of America Abstracts with Programs, 2012 Annual Meeting, Charlotte, North Carolina, 4-7 November 2012.

Geosciences Newsletter - 2012, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 5, No. 1

• Faculty Updates
• Faculty Updates
• Deanna Romanosky
• Publications
• MGRRE
• Alumni Award
• Gifts
• Grants
• Endowments

The Role Of Case-Hardening In The Development And Preservation Of Narrow, Vertical-Walled Canyons In Adršpach-Teplice, Czech Republic, Shawn Austin Wiggins

Theses and Dissertations

The geomorphology at Adršpach-Teplice, Czech Republic is dominated by vertical-walled, fracture-controlled features including slot canyons, gorges and pillars. Surfaces of canyon walls in Adršpach are case-hardened and more resistant to erosion than the bulk of the sandstone, which appears to be fundamental to the formation and preservation of canyons. Core and whole rock samples from Adršpach-Teplice were analyzed in thin section, including SEM analysis with cathodo luminescence. XRF and XRD analyses indicated that silica case-hardened surfaces are chemically and mineralogically similar to the rock interior, while iron case-hardened surfaces have an increase in iron present at the surface as the …

Predictability Of Biomass Burning In Response To Climate Changes, A.-L. Daniau, Megan Walsh

All Faculty Scholarship for the College of the Sciences

Climate is an important control on biomass burning, but the sensitivity of fire to changes in temperature and moisture balance has not been quantified. We analyze sedimentary charcoal records to show that the changes in fire regime over the past 21,000 yrs are predictable from changes in regional climates. Analyses of paleo- fire data show that fire increases monotonically with changes in temperature and peaks at intermediate moisture levels, and that temperature is quantitatively the most important driver of changes in biomass burning over the past 21,000 yrs. Given that a similar relationship between climate drivers and fire emerges from …

Transition In The Fractal Geometry Of Arctic Melt Ponds, C. Hohenegger, B. Alali, K. R. Steffen, D. K. Perovich, K. M. Golden

Dartmouth Scholarship

During the Arctic melt season, the sea ice surface undergoes a remarkable transformation from vast expanses of snow covered ice to complex mosaics of ice and melt ponds. Sea ice albedo, a key parameter in climate modeling, is determined by the complex evolution of melt pond configurations. In fact, ice–albedo feedback has played a major role in the recent declines of the summer Arctic sea ice pack. However, understanding melt pond evolution remains a significant challenge to improving climate projections. By analyzing area–perimeter data from hundreds of thousands of melt ponds, we find here an unexpected separation of scales, where …

Examining The Impact Of Pau Jacaré (Piptadenia Gonoacantha) Growth On Soil Fertility In The Brazilian Atlantic Rainforest, Aleksandra Ponomareva

Environmental Analysis Program Mellon Student Summer Research Reports

The Atlantic Rainforest of Brazil is an area of astounding diversity in both flora and fauna, taking its place among the top five “biodiversity hotspots” in the world. However, in the past 40 or 50 years the area has been increasingly threatened by the presence of humans – approximately 93% of the Rainforest has disappeared as a result of exploitation (Turner 2004). Unsustainable farming practices, as well as logging, cattle ranching and mining activities have caused soil infertility, water depletion, erosion and destruction of ecosystems. This project examines the effects of the Pau Jacaré, Piptadenia gonoacantha, tree on soil health …

Geological Survey Of Cueva Guhamra, Cassandra L. Baumgartner

Independent Study Project (ISP) Collection

As it has been said by many of the great scientists before us, “Geology Rocks.” While this may not be entirely scientific, the debatably of this statement as a whole truth is next to zero. But we mustn’t forget the latest contester in the battle of rocks- that is- Speleology. As the boundaries of science are continually being stretched to greater distances, we see the development of new branches of science to accommodate these boundary-breakthroughs. Speleology refers to the study of caves and is considered to be relatively new and unexplored. Generally, a cave survey (essentially a quantified and tangible …

Geogram 2012, David J. Keeling, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

A Centennial Record Of Paleosalinity Change In The Tidal Reaches Of The Potomac And Rappahannock Rivers, Tributaries To Chesapeake Bay, Neil E. Tibert, Lindsay J. Walker, William P. Patterson, J. Bradford Hubeny, Emma Jones, Olivia R. Cooper

Virginia Journal of Science

Gravity and push cores from the Potomac and Rappahannock Rivers (Virginia Tidewater) were collected from central and proximal estuarine zones with known seasonal salinity stratification. The lowermost microfossil associations in the cores comprise alternating ostracode populations of Cyprideis salebrosa and Cytheromorpha. This microfossil association gives way to an oligohaline association dominated by the freshwater ostracode Darwinula stevensoni. Stable oxygen isotope values (δ¹⁸O) of Rapphannock Cyprideis salebrosa are highly variable ranging between -6.6 to -3.2‰ VPDB. δ¹⁸O values for Potomac Cytheromorpha fuscata range from -8.2 to -3.2‰ VPDB. Positive excursions in δ¹⁸O values …

Documenting Change At Upper Hamburg Bend: Nebraska's First Side-Channel Restoration, Brandon L. Eder, Gerald Mestl

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

In 1996 a side channel was excavated on 629 hectares of former agricultural land at Upper Hamburg Bend on the Missouri River in Otoe County, NE. This was the first side channel constructed on the Missouri River in an attempt to restore lost aquatic habitat. The initial design was for an approximately 4,200 m long side channel to be constructed with a 3 m bottom width. Development ofthe site was to be dependent on flows diverted from the main channel of the river with a final projected top width of 61 m. The side channel was completed in the spring, …

Demographic And Genetic Consequences Of Small Population Size In Remnant Populations Of Arabis Georgiana Harper (Georgia Rockcress), Alicia M. Garcia

Theses and Dissertations

The goal of this thesis is to provide a greater scientific understanding of the demographic and genetic consequences of small population size in remnant populations of Arabis georgiana Harper (Georgia Rockcress). Specifically, 1 ) traits associated with phenological progression, fitness and reproductive success were compared between naturally occurring "native" plants and plants grown ex situ and subsequently restored to one of the largest remaining populations of A. georgiana, and 2) a preliminary analysis of population genetic structure in remnant populations across the species' range was performed. In addition to updating census information on remnant populations of A. georgiana, chapter one …

Intercalibration Studies Of 210Po And 210Pb In Dissolved And Particulate Seawater Samples, Thomas Church, Sylvain Rigaud, Mark Baskaran, Anupam Kumar, Jana Friedrich, Pere Masque, Viena Puigcorbé, Guebuem Kim, Olivier Radakovitch, Gi Hong, Hui Choi, Gillian Stewart

Environmental Science and Geology Faculty Research Publications

Documented is an intercalibration (IC) exercise for both ²¹⁰Po and ²¹⁰Pb in seawater aliquots distributed between up to eight international laboratories that followed individual protocols. Dissolved and particulate samples were provided by GEOTRACES during two IC cruises at baseline stations in the North Atlantic and North Pacific oceans. Included were surface and/or deep dissolved and particulate samples at each site, plus complete profiles analyzed by the laboratory of the lead author. An unspecified solid phase standard was also distributed with ²¹⁰Po and ²¹⁰Pb in secular equilibrium to confirm spike calibrations. The ²¹⁰Po activities reported n …