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Earth Sciences

Theses/Dissertations

2007

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Impacts Of Acid Mine Drainage On Carbon Cycling In Receiving Streams, Ernest W. Fonyuy Jan 2007

Impacts Of Acid Mine Drainage On Carbon Cycling In Receiving Streams, Ernest W. Fonyuy

Doctoral Dissertations

"Field and laboratory investigations of acid mine drainage (AMD) contaminated and uncontaminated waters were conducted in order to determine and model processes and reaction mechanisms that control dissolved inorganic carbon (DIC) transformation and shifts in isotope ratio of DIC (Δ¹³CDIC). The results show that AMD caused variable pH changes, overall decreases in Fe²⁺, alkalinity, and DIC, and increases in (Δ¹³CDIC) in receiving streams. AMD caused more than 50 to > 98% seasonal DIC loss in stream water through CO₂ degassing. High DIC losses corresponded to high Fe²⁺ and lower or no HCO₃⁻ in the water samples, because …


Incipient Continental Rifting: Insights From The Okavango Rift Zone, Northwestern Botswana, Baraka D. Kinabo Jan 2007

Incipient Continental Rifting: Insights From The Okavango Rift Zone, Northwestern Botswana, Baraka D. Kinabo

Doctoral Dissertations

"In this dissertation aeromagnetic, gravity, and Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data from the Okavango Rift Zone in northwest Botswana are used to map the distribution of rift and basement structures. The distribution of these structures provide useful insights into the early stages of continental rifting. The objectives of this study are (1) assessing the role of pre-existing structures on rift basin development, (2) characterizing the geometry of the nascent rift basins, (3) documenting fault growth and propagation patterns, and (4) investigating the border fault development"--Abstract, page iv.


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

Browse all Theses and Dissertations

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 …


Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields Jan 2007

Biogeochemistry And Phytoplankton Dynamics In The Ross Sea, Antarctica, Amy Rebecca Shields

Dissertations, Theses, and Masters Projects

The Ross Sea, Antarctica seasonal phytoplankton bloom is one of the largest in the Southern Ocean. This project focuses on the biological pump, which removes carbon from the surface ocean to the deep ocean through the settling of particulate organic matter, the advection of dissolved organic carbon, and active flux due to vertical migration of zooplankton. The objective of this study was to focus on three interrelated components of the biological pump including sedimentation, photosynthetic rates and grazing. The study was conducted in coordination with the Interannual Variability in the Antarctic-Ross Sea program, which covered the time period between 2001--2005. …


The Impact Of Drainage Ditches On Salt Marsh Flow Patterns, Sedimentation And Morphology: Rowley River, Massachusetts, Lynsey E. Lemay Jan 2007

The Impact Of Drainage Ditches On Salt Marsh Flow Patterns, Sedimentation And Morphology: Rowley River, Massachusetts, Lynsey E. Lemay

Dissertations, Theses, and Masters Projects

Salt marshes along many tidal systems in New England have been ditched since colonial times. These ditches have been thought to help control mosquito populations and increase salt marsh hay production by improving water drainage from the marsh. Although these ditches are prominent geomorphic features, little quantitative work has focused on how these man-made ditches may alter marsh hydrology and geomorphology. This study attempts to quantify the ways in which ditches alter sediment and water transport pathways and how that affects the overall morphology and surface geology. This study also addresses treatment affects on sedimentation from fertilization and fish removal …


Evolution Of An Allochthonous Salt System, Southern Mars-Ursa Basin, Northern Gulf Of Mexico, Angela Bordelon Pell Jan 2007

Evolution Of An Allochthonous Salt System, Southern Mars-Ursa Basin, Northern Gulf Of Mexico, Angela Bordelon Pell

LSU Master's Theses

This study examines the evolution of an allochthonous salt system in the southern Mars-Ursa basin. A seismic stratigraphic framework and biostratigraphic markers provided constraints on basin development and sediment accumulation from late Miocene to middle Pliocene time. External geometries of tectonostratigraphic packages are identified in the study area and are combined with analyses of brittle deformation to track salt evacuation in the study area. External geometries identified in the study include: wedge, layer and trough. Fifty-nine faults were mapped in basin and suprasalt strata and five phases of brittle deformation were identified. Eight evolutionary stages were identified for the time …


Plant Assemblage Structure On Barrier Island ‘Pimple’ Dunes At The Virginia Coast Reserve Long-Term Ecological Research Site, Brett A. Mcmillan Jan 2007

Plant Assemblage Structure On Barrier Island ‘Pimple’ Dunes At The Virginia Coast Reserve Long-Term Ecological Research Site, Brett A. Mcmillan

Biological Sciences Theses & Dissertations

The habitats at the VCR LTER that were the focus of the current study are the Hog Island and Parramore Island 'pimples', small, rounded dunes forming along main dune ridges of the barrier islands. There are distinct plant assemblage zones found on pimples, although most of these dunes are 10–20 m in diameter. Hypotheses of the study were that fresh water availability was a main determinant of differences between assemblages and that pimple size and location would influence diversity and assemblage structure. Research goals were (1) to describe the plant assemblages on pimples, (2) to relate edaphic and geomorphological factors …


Methane Potential Of Upper Fort Union Formation Sandstones, Campbell County, Wyoming, Michael J. Blackstone Jan 2007

Methane Potential Of Upper Fort Union Formation Sandstones, Campbell County, Wyoming, Michael J. Blackstone

Theses and Dissertations

Coalbed methane has been produced from the coalbeds of the Upper Fort Union Formation in the Powder River Basin for many years. The sandstones associated with these coals have also proven to be gas-charged, but industry has done little with the sandstones thus far. The purpose of this study is to determine the paleoenvironrnent responsible for the deposition of the coal and sandstone bodies in an attempt to locate gas-charged sandstone bodies in the Tongue River Member of the Fort Union Formation.

The 30-mile by 90-mile study area was chosen because of the presence of a decrease in thick coalbed …


Developing A Rapid Method For Assessing The Physical Stability Of Streams In Minnesota's Agassiz Beach Ridges, Abigail V. Franklund Jan 2007

Developing A Rapid Method For Assessing The Physical Stability Of Streams In Minnesota's Agassiz Beach Ridges, Abigail V. Franklund

Theses and Dissertations

This thesis assessed the physical characteristics and stability of selected western Minnesota streams that cross the eastern beach ridges of glacial Lake Agassiz. Stream and river channels in this area host unusually diverse aquatic habitat and biodiversity, but incompatible land use along channels and in watersheds impair their quality and function. Previous rapid assessment protocols have been developed for stream attributes and stability, but these methods have been developed elsewhere in the United States and are not necessarily appropriate for western Minnesota’s unique geology and landscape.

A rapid reconnaissance method was developed to assess stream conditions using an integrated numerical …


Investigation Of A Possible Lead-Lag Relationship Between The Innuitian And Laurentide Ice Sheets, Arctic Canada, Paula Zimmerman Jan 2007

Investigation Of A Possible Lead-Lag Relationship Between The Innuitian And Laurentide Ice Sheets, Arctic Canada, Paula Zimmerman

OES Theses and Dissertations

Peaks of iron-rich grains in Arctic Ocean sediment cores matched to the Laurentide and Innuitian Ice Sheets appear to show a lead-lag relationship during the Late Pleistocene when grain abundances are plotted against time and depth below sea floor. Cores from across the Arctic have been analyzed to determine if this is the case. Of the six IRD events identified, the Innuitian leads 68% of the time with 26% of events in all cores occurring simultaneously. The Innuitian seems to lead 33.3% of the time when peaks from the Innuitian and Laurentide occur within close proximity (less than 1 cm), …


Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray Jan 2007

Analysis Of Miocene Stratigraphy And Sedimentology In The Ross Sea, Antarctica: A First Order Test Of Proxy Based Climate Interpretations, Samuel Gray

LSU Master's Theses

During the Cenozoic, the climate progressed from global warmth into an icehouse world. This study investigates the links between the development of the climate and cryosphere using sediment flux and stratal geometries. The current polar conditions are characterized by dry basal conditions, which due to minimal melt water produce significantly less sediment than their temperate counterparts. Therefore, the transition from temperate to polar conditions should have resulted in marked decrease in sediment flux and change in stratal geometries in adjacent marine margins. Regional seismic stratigraphic evidence clearly suggests that ice has been intermittently grounded on the Ross Sea outer continental …


Fluid Flow In The Central North Slope Foreland Basin, Alaska, Anna Marie Bélanger Jan 2007

Fluid Flow In The Central North Slope Foreland Basin, Alaska, Anna Marie Bélanger

LSU Master's Theses

Previous studies of the areal variations in heat flow and spatial variations in formation water salinity and hydraulic head are consistent with the existence of a currently active, topographically-driven regional fluid flow regime in the National Petroleum Reserve Alaska (NPRA) portion of the western North Slope foreland basin. This conclusion is also supported by the results of numerical modeling of fluid flow and heat transport in the area. This work has now been extended to the east. The results of this study demonstrate that the Permian though Cenozoic age sediments of the central North Slope foreland basin have been significantly …


Characteristics And Processes Of Degradation On Normal Fault Scarps In Basalt, Central Oregon And Northern California, Kelsay Davis Jan 2007

Characteristics And Processes Of Degradation On Normal Fault Scarps In Basalt, Central Oregon And Northern California, Kelsay Davis

WWU Graduate School Collection

Normal faults that break the surface create scarps. Scarps in alluvium degrade predictably so that time since formation can be inferred from scarp profile, however, scarps in jointed bedrock, such as basalt, do not degrade according to previous models. Understanding the processes involved in degradation of scarps in jointed basalt may lead to the formation of a degradation model.

I use survey data and statistical analyses from 36 scarps in central Oregon and northern California, to determine the characteristics that play a dominant role in scarp degradation in jointed basalt. These data indicate that scarp facing direction, column height, and …


Quantifying The Glacial Meltwater Component Of Streamflow In The Middle Fork Nooksack River, Whatcom County, Wa, Using A Distributed Hydrology Model, Carrie B. Donnell Jan 2007

Quantifying The Glacial Meltwater Component Of Streamflow In The Middle Fork Nooksack River, Whatcom County, Wa, Using A Distributed Hydrology Model, Carrie B. Donnell

WWU Graduate School Collection

Glacial meltwater is a vital component of rivers and streams in glaciated regions such as the Pacific Northwest, and can be critical for municipal water supplies, power generation, and habitat issues. The Middle Fork of the Nooksack River is fed by meltwater from Deming Glacier on Mount Baker, WA. The City of Bellingham has been diverting water from the Middle Fork since 1962 to supplement the water supply, and to maintain water quality in Lake Whatcom, the water source for the city. Because of regulations, water is only diverted when the Middle Fork exceeds minimum acceptable streamflow. A concern for …


Application Of A Nitrate Fate And Transport Model To The Abbotsford-Sumas Aquifer, Whatcom County, Washington, Margo A. Burton Jan 2007

Application Of A Nitrate Fate And Transport Model To The Abbotsford-Sumas Aquifer, Whatcom County, Washington, Margo A. Burton

WWU Graduate School Collection

The Abbotsford-Sumas aquifer is a shallow, unconfined aquifer located in an agriculturally intensive area in northwestern Washington and southwestern British Columbia. Due to aquifer characteristics and surface land use, the Abbotsford-Sumas aquifer has had a history of nitrate contamination from non-point sources. As such, nutrient managers are interested in predictive tools to evaluate management strategies. I assessed the effectiveness of a GIS based nitrate fate and transport model developed specifically for the Abbotsford-Sumas aquifer by Almasri and Kaluarachchi (2004) as a predictive tool for nutrient management. This model couples four sub-models that collectively estimate nutrient loading, predict soil-nitrogen dynamics (NLEAP), …


Applicability Of The Nlos Model For Predictions Of Soil Water Movement And Nitrogen Transport In An Agricultural Soil, Agassiz, Bc, Heather R. Hirsch Jan 2007

Applicability Of The Nlos Model For Predictions Of Soil Water Movement And Nitrogen Transport In An Agricultural Soil, Agassiz, Bc, Heather R. Hirsch

WWU Graduate School Collection

The Abbotsford-Sumas aquifer is a shallow, unconfined aquifer in northern Whatcom County, WA and southern British Columbia, Canada that is contaminated with nitrates due to agricultural land use. Currently, conservation managers rely on Post-Harvest Soil Nitrate Tests (PHSNTs) to predict nitrate leaching potential to the aquifer. However, these tests have limitations as an assessment tool because of their inaccuracy. Therefore, US and Canadian government agencies are considering the NLEAP on STELLA (NLOS) leaching model as an additional tool for assessing nutrient management strategies. NLOS is an adaptation of the Nitrogen Leaching and Economic Analysis Package (NLEAP) model. I examined the …


Oblique Photogrammetric Analysis Of Dome Growth At Mount St. Helens Volcano, 2004 – 2007, Angela K. Diefenbach Jan 2007

Oblique Photogrammetric Analysis Of Dome Growth At Mount St. Helens Volcano, 2004 – 2007, Angela K. Diefenbach

WWU Graduate School Collection

This project is an oblique photogrammetric survey of the 2004-2007 dome-building eruption of Mount St. Helens volcano with two primary objectives: (1) to evaluate the potential of a new rapid and low-cost technique to create digital elevation models (DEMs) and subsequently calculate dome volumes and extrusion rates at Mount St. Helens; and (2) to attempt to understand mechanics associated with lava dome extrusion and collapse by analyzing volumetric and extrusion rate measurements in the context of dome height measurements, seismicity data, and migration of the locus of dome growth.

The new method uses sets of oblique aerial photographs, acquired from …


Petrographic Signature For The Whidbey Formation, Jonathan Peterson Jan 2007

Petrographic Signature For The Whidbey Formation, Jonathan Peterson

WWU Graduate School Collection

The late Pleistocene Whidbey Formation occupies a region on and around Whidbey Island, Washington, that received both northern-derived glacial sediments and eastern-derived nonglacial sediments. Distinguishing between glacial outwash and nonglacial sediments of the Whidbey Formation and the younger Olympia beds has been problematic where stratigraphic sections are incomplete. For the Whidbey Formation, discontinuous deposits of sand, clay, peat and silt that stem from meandering streams on floodplains have not been fully characterized, petrographically. Recent documentation (Dragovich and others, 2005) of dacitic channel and lahar-runout facies on northern Whidbey Island spurred petrographic analysis of various sands from across the whole region …