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Cliff-Top Dunes In The Lower Chippewa River Valley Of West-Central Wisconsin, Jason Millett Jan 2019

Cliff-Top Dunes In The Lower Chippewa River Valley Of West-Central Wisconsin, Jason Millett

All Graduate Theses, Dissertations, and Other Capstone Projects

The purpose of this Master’s thesis is to investigate recently identified cliff-top sand dunes located within the Lower Chippewa River Valley (LCRV), Wisconsin, USA. Research within the LCRV notes the existence of a variety of aeolian deposits, but a comprehensive explanation of their complete spatial distribution, genesis, age, and paleoenvironmental significance does not exist. In particular, stabilized cliff-top dunes with a parabolic form remain poorly understood. This problem is exacerbated by a lack of clarity in the literature regarding the genesis of dunes in a cliff-top position. Therefore, this thesis begins by reviewing the literature concerning sand dunes in cliff-top …

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Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas Jan 2019

Paleomagnetic Investigation Of Igneous Rocks Deformed By The Keweenaw Fault In The Northwestern Keweenaw Peninsula., Daniel Trekas

Dissertations, Master's Theses and Master's Reports

One of the most prominent structural features associated with the ~1.1 Ga Midcontinent Rift (MCR) system is the >350 km long Keweenaw Fault that bisects the Keweenaw Peninsula, separating the MCR-related Portage Lake Volcanics (PLV) and the younger Jacobsville Sandstone (JS). The fault trend is NE-NNE over most of its length, but changes to an easterly direction along the shore of Bête Grise Bay near the end of the peninsula. Conventionally, the Keweenaw Fault has been considered to be a continuous reverse (dip-slip) fault formed by inversion of an original rift-bounding normal fault during the Grenville Orogeny. However, recent mapping …

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Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen Jan 2019

Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen

Pomona Senior Theses

Keeping out invasive species may, upon first review, seem like a trivial environmental cry from ecologists and deep environmentalists; a belated wish to return to an undeveloped world where nature was pristine. However invasive species create problems that impact all of us and can have far more severe consequences than changing a stunning landscape. These problems are heightened in islands like Hawaii, where the fragile ecosystems have developed over centuries of evolution and adaptation. The introduction of a disease-carrying mosquito can put the people of Hawaii at risk to many vector-born illnesses and create an epidemic, taking human life. The …

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How To Search For Life In Martian Chemical Sediments And Their Fluid And Solid Inclusions Using Petrographic And Spectroscopic Methods, Kathleen C. Benison Jan 2019

How To Search For Life In Martian Chemical Sediments And Their Fluid And Solid Inclusions Using Petrographic And Spectroscopic Methods, Kathleen C. Benison

Faculty & Staff Scholarship

Abundant resources and efforts have been employed in the search for life on Mars. Satellites, landers, and rovers have tested atmospheric gases, general sediment and rock compositions, and images of Mars surface in an effort to detect biosignatures left by any possible modern or ancient life. Chloride and sulfate minerals suggestive of past acid saline lakes have been found on Mars. In terrestrial acid brine environments, these minerals trap microorganisms and organic compounds and preserve them within fluid inclusions and as solid inclusions for long geologic time periods. Some cells remain viable, especially in the isolated, microscopic aqueous environments of …

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Sedimentological And Mineralogical Characteristics Of Red Soil In South Pirin Mountains(Southwest Bulgaria), Rossitza Kenderova, Ahinora Baltakova, Marlena Yaneva Jan 2019

Sedimentological And Mineralogical Characteristics Of Red Soil In South Pirin Mountains(Southwest Bulgaria), Rossitza Kenderova, Ahinora Baltakova, Marlena Yaneva

Turkish Journal of Earth Sciences

The northernmost derivation of the Mediterranean climatic influence and the wide distribution of carbonate rocks are factors that could explain red soils distribution in the lands of Southern Bulgaria. However, due to the mainly mountainous landscape, red soils can be found only on certain spots in Bulgaria. One of the most typical examples of red soil can be found in the lands of Nova Lovcha Village in Bulgaria, but this area was not studied in detail due to its border position. In this study, the catena principle was used to estimate the parental material and slope drainage relationships as factors …

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Late Quaternary Landscape Evolution Of The Southern Marmara Region:Paleogeographic Implications For Settlements, Nw Turkey, Ni̇zametti̇n Kazanci, Zeynep Ergun, Kaan İren, Suzanne A. Leroy, Sonay Boyraz Aslan, Mehmet Sali̇m Öncel, Koray Koç, Alper Gürbüz Jan 2019

Late Quaternary Landscape Evolution Of The Southern Marmara Region:Paleogeographic Implications For Settlements, Nw Turkey, Ni̇zametti̇n Kazanci, Zeynep Ergun, Kaan İren, Suzanne A. Leroy, Sonay Boyraz Aslan, Mehmet Sali̇m Öncel, Koray Koç, Alper Gürbüz

Turkish Journal of Earth Sciences

This study presents the late Quaternary evolution of the southern Marmara region in northwestern Turkey and discusses the suitability of the area for settlements. It is based on interpretation of sediment analyses together with radiometric dates obtained from drilling cores. As three-fourths of the southern Marmara region (ca. 30,000 km2) is covered by the Susurluk Drainage Basin (SDB), the study focuses on this basin. The SDB has a concave surface morphology dipping northward, with highlands in the south (ca. 1300-1700 m a.s.l.) and lowlands in the north (ca. 0-250 a.s.l.). Lake Manyas, Lake Ulubat, and south-north flowing rivers, together with …

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The Early Eocene Ekmekçi Granodiorite Porphyry In The Karacabey Region(Sakarya Zone, Nw Turkey), Gürsel Sunal, Mehmet Korhan Erturaç, Gülteki̇n Topuz, Aral Okay, Thomas Zack Jan 2019

The Early Eocene Ekmekçi Granodiorite Porphyry In The Karacabey Region(Sakarya Zone, Nw Turkey), Gürsel Sunal, Mehmet Korhan Erturaç, Gülteki̇n Topuz, Aral Okay, Thomas Zack

Turkish Journal of Earth Sciences

The Ekmekçi granodiorite porphyry is a unit in the E-W trending, postcollisional Eocene magmatic rocks of northern Anatolia. It occurs as a relatively small stock, but represents a link between plutonic and volcanic rocks. This Early Eocene granodiorite porphyry intruded into the Upper Triassic rocks of the Karakaya complex in the Sakarya Zone. In this study we present geochemical and zircon U-Pb LA-ICP-MS age data to contribute to understanding the Early Tertiary postcollisional tectonic setting of NW Anatolia. The granodiorite porphyry includes plagioclase, quartz, hornblende, K-feldspar, biotite, and minor zircon, apatite, sphene, and opaque minerals. The stock displays medium-K calc-alkaline …

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Holocene Fire History Reconstruction Of A Mid-Evaluation Mixed-Conifer Forest In The Eastern Cascades, Washington, Zoe Rushton Jan 2019

Holocene Fire History Reconstruction Of A Mid-Evaluation Mixed-Conifer Forest In The Eastern Cascades, Washington, Zoe Rushton

All Master's Theses

Fire histories of mid-elevation mixed-conifer forests (MEMC) are uncommon, particularly in the eastern Cascades of Washington. As a result, fire regimes and the effects of 20th century fire suppression in these forests are not well understood. In the summer of 2014 a 7.80 meter-long sediment core was extracted from Long Lake, located approximately 45 km west of Yakima, WA, which exists in a grand fir-dominated mixed-conifer forest. Fire activity for the Long Lake watershed was reconstructed using macroscopic charcoal analysis and pollen analysis was used to reconstruct vegetation change through time. Charcoal results show low fire activity in the early …

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Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad Jan 2019

Holocene Periods Of Aggradation And Incision, Hanson Creek, Washington, Levi Earl Windingstad

All Master's Theses

The causes and timing of cycles of aggradation and incision in the Hanson Creek drainage in central Washington provide insight into changes in channel morphology and paleoenvironment within the region over the last 8000 years. Stratigraphically and spatially coincident archaeological evidence reveals information related to human occupation during the latter half of the epoch. Using LiDAR imagery and field surveys, recent processes such as degree of modern channel incision, accumulation of valley floor sediment, channel morphology and gradient were evaluated. The spatial distribution of these channel characteristics was assessed in relation to proximal landforms such as colluvial deposits, basalt outcrops, …

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Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt Jan 2019

Primary Report Of First Documentation Of Mammal Footprints From The Late Oligocene Inthe Sivas Basin, Turkey, Beki̇r Levent Mesci̇, Ahmet Cem Erkman, Şaki̇r Önder Özkurt

Turkish Journal of Earth Sciences

The footprints in this study, which were considered to have been made by ungulates, were discovered on mudstone that was approximately 5 cm thick, near an abundant mud-cracked plane located on the stratigraphic subsurface of the late Oligocene Karayün Formation, which crops out over wide areas in southern Sivas (Turkey) and has terrestrial, fluvial sediment characteristics. These ungulate footprints documented from the late Oligocene of the Karayün Formation in southern Sivas represent the first reported vertebrates in Anatolia. The footprints of three different species of ungulates were identified. The shapes, depth, and widths of the footprints provided some basic ichnotaxonomic …

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Glacial Deposits, Vol. 44, 2019, Department Of Geography, Geology, And The Environment Jan 2019

Glacial Deposits, Vol. 44, 2019, Department Of Geography, Geology, And The Environment

Glacial Deposits

Newsletter of the Department of Geography, Geology, and the Environment

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Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker Jan 2019

Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Floodplain ponds and wetlands are productive and biodiverse ecosystems, yet they face multiple threats including altered hydrology, land use change, and non-native species. Protecting and restoring important floodplain ecosystems requires understanding how organisms use these habitats and respond to altered environmental conditions. We developed Bayesian models to evaluate occupancy of six amphibian species across 103 off-channel aquatic habitats in the Chehalis River floodplain, Washington State, USA. The basin has been altered by changes in land use, reduced river–wetland connections, and the establishment of non-native American bullfrogs (Rana catesbeiana = Lithobates catesbeianus) and centrarchid fishes, all of which we hypothesized could …

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Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth Jan 2019

Mechanics And Historical Evolution Of Sea Level Blowouts In New York Harbor, Praneeth Gurumurthy, Philip Orton, Stefan A. Talke, Nickitas Georgas, James F. Booth

Civil and Environmental Engineering Faculty Publications and Presentations

Wind-induced sea level blowouts, measured as negative storm surge or extreme low water (ELW), produce public safety hazards and impose economic costs (e.g., to shipping). In this paper, we use a regional hydrodynamic numerical model to test the effect of historical environmental change and the time scale, direction, and magnitude of wind forcing on negative and positive surge events in the New York Harbor (NYH). Environmental sensitivity experiments show that dredging of shipping channels is an important factor affecting blowouts while changing ice cover and removal of other roughness elements are unimportant in NYH. Continuously measured water level records since …

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Utilization Of Various Methods And A Landsat Ndvi/Google Earth Engine Product For Classifying Irrigated Land Cover, Andrew Nemecek Jan 2019

Utilization Of Various Methods And A Landsat Ndvi/Google Earth Engine Product For Classifying Irrigated Land Cover, Andrew Nemecek

Graduate Student Theses, Dissertations, & Professional Papers

Methods for classifying irrigated land cover are often complex and not quickly reproducible. Further, moderate resolution time-series datasets have been consistently utilized to produce irrigated land cover products over the past decade, and the body of irrigation classification literature contains no examples of subclassification of irrigated land cover by irrigation method. Creation of geospatial irrigated land cover products with higher resolution datasets could improve reliability, and subclassification of irrigation by method could provide better information for hydrologists and climatologists attempting to model the role of irrigation in the surface-ground water cycle and the water-energy balance. This study summarizes a simple, …

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Coastal Wetlands: A Synthesis, Charles S. Hopkinson, Eric Wolanski, Mark M. Brinson, Daonald R. Cahoon, Gerardo M.E. Perillo Jan 2019

Coastal Wetlands: A Synthesis, Charles S. Hopkinson, Eric Wolanski, Mark M. Brinson, Daonald R. Cahoon, Gerardo M.E. Perillo

United States Geological Survey: Staff Publications

What are coastal wetland ecosystems, what are their limits of distribution, and where do they exist in the overall coastal landscape? There are several general definitions for wetlands, but the Ramsar definition is likely the most broadly encompassing (http://www.ramsar. org/), whereas others are more focused definitions tailored to country-specific protection and management policies (Mitsch and Gosselink, 2006). We offer a very general approach rather than a precise definition: coastal wetlands are ecosystems that are found within an elevation gradient that ranges between subtidal depths where light penetrates to support photosynthesis of benthic plants to the landward edge where the sea …

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Using Paleolimnology To Establish Baseline Conditions For Metal Contaminants In Advance Of Proposed Mining To Inform A Northern Community-Led Aquatic Monitoring Program, Tłı̨Chǫ Lands, Northwest Territories, Canada., James Telford Jan 2019

Using Paleolimnology To Establish Baseline Conditions For Metal Contaminants In Advance Of Proposed Mining To Inform A Northern Community-Led Aquatic Monitoring Program, Tłı̨Chǫ Lands, Northwest Territories, Canada., James Telford

Theses and Dissertations (Comprehensive)

The Marian Watershed Stewardship Program (MWSP), a community-driven aquatic ecosystem monitoring program, was developed by the Tłı̨chǫ Government to address concerns regarding the cumulative impacts of multiple potential stressors. In particular, the MWSP aims to develop methods that will be effective for detecting potential pollution from the proposed cobalt-gold-copper-bismuth NICO mine within Tłı̨chǫ Lands. In collaboration with the MWSP, paleolimnological methods and geochemical normalization are used to establish pre-mine baselines of lake sediment metals concentrations in the Marian River watershed prior to mine development. This baseline framework can be used to assess for pollution from surficial sediment once the mine …

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Biogeochemical And Hydrological Impacts Of A Low-Severity Wildfire In The Wetland-Dominated Zone Of Discontinuous Permafrost, Caren J. Ackley Jan 2019

Biogeochemical And Hydrological Impacts Of A Low-Severity Wildfire In The Wetland-Dominated Zone Of Discontinuous Permafrost, Caren J. Ackley

Theses and Dissertations (Comprehensive)

Northern regions are experiencing rapid climate warming. As these regions warm, the occurrences of naturally ignited wildfires are increasing in frequency, severity and area burned, calling for a more thorough understanding of post-fire eco-hydrological impacts. Changes in runoff chemistry, and soil moisture and thermal regimes, have been attributed to the significant loss of organic matter (OM) and exposure of deeper soils, leading to enhanced permafrost degradation, ground surface subsidence and the conversion of peat landscapes from long-term C sinks to sources. However, low-severity wildfires often result in minor OM loss. Due to the significant and immediate threats posed to the …

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Development And Application Of Hydrological And Limnological Monitoring In Lake-Rich Landscapes Of Canada’S Subarctic National Parks, Hilary Emma White Jan 2019

Development And Application Of Hydrological And Limnological Monitoring In Lake-Rich Landscapes Of Canada’S Subarctic National Parks, Hilary Emma White

Theses and Dissertations (Comprehensive)

Arctic and subarctic environments are being adversely influenced by human-caused climate change across our entire planet. Canada’s northern freshwater ecosystems are influenced by a variety of environmental stressors and are particularly sensitive to climate change, since small shifts in climate have the potential to substantially alter their hydrological, limnological, and biogeochemical conditions. Some other indirect effects on northern freshwater landscapes are the expansion of vegetation as well as changes in wildlife and waterfowl populations and distribution. It is, therefore, critical to understand the observed and predicted influences of climate change and other environmental stressors on these northern freshwater environments dominant …

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Snowmelt Detection On Alpine Glaciers Using Synthetic Aperture Radar Time Series, Corey Scher Jan 2019

Snowmelt Detection On Alpine Glaciers Using Synthetic Aperture Radar Time Series, Corey Scher

Dissertations and Theses

Hindu Kush Himalayan (HKH) glaciers serve as some of the most sensitive indicators of changes in global climate. These glaciers shape the hydrologic dynamics of river systems supplying freshwater to over 2 billion people throughout Asia and regulate the geochemistry of sensitive aquatic alpine ecosystems. As snowmelt onsets sooner, lasts longer, and snowfields retreat due to increases in global temperature, the hydrologic dynamics of catchments draining HKH threaten to change the availability of surface freshwater resources for nearly one fifth of the global population, disturb sensitive aquatic habitat, and precipitate hazards associated with glacier wasting. Informed planning and decision-making around …

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Conservation Agriculture In The Heartland: Farmer Perceptions Of Soil Health And The Adoption Of Cover Crops, Lillian Clarissa Cobo Jan 2019

Conservation Agriculture In The Heartland: Farmer Perceptions Of Soil Health And The Adoption Of Cover Crops, Lillian Clarissa Cobo

Graduate Research Theses & Dissertations

The benefits of cover crops are widely recognized by those interested in conservation agriculture and soil health. These benefits include soil erosion control, nutrient loss reduction, and overall improvement of soil health. However, while these benefits are well-documented, the adoption rate of cover crops in the American Heartland remains astoundingly low. While some studies have attempted to determine the reasons for this low adoption rate, the information relating to how farmer perceptions of soil health impact cover crop adoption is almost nonexistent. Furthermore, there is a clear absence of mixed method studies in the literature relating to this subject. This …

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Water Quality And Small Unmanned Aerial System Photogrammetry Of Boeng Cheung Ek Wastewater Treatment Wetland, Phnom Penh, Cambodia, Samuel Vesal Mallow Jan 2019

Water Quality And Small Unmanned Aerial System Photogrammetry Of Boeng Cheung Ek Wastewater Treatment Wetland, Phnom Penh, Cambodia, Samuel Vesal Mallow

Graduate Research Theses & Dissertations

Boeng Cheung Ek wetland is a large, peri-urban, free water surface, natural wastewater treatment wetland that services approximately 90% of combined storm water and untreated sewage from the city of Phnom Penh, Cambodia, population over 1.5 million. Due to monsoon rainfall and connectivity to the Mekong River, the wetted area cycles between 13 km2 and 20 km2 annually. The objective of this study is to characterize the spatiotemporal variability of contaminants in wetland surface water and groundwater. Dissolved ions including ammonium, nitrate-N (as NO3), phosphate, and chloride, along with E. coli, trace metals, δH, δ18O, and physicochemical parameters were determined …

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Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia Jan 2019

Ductile Deformation In The Central Panamint Mountains - A Multi-Disciplinary Approach To A Multi-Dimensional Problem., Tai Antonia Subia

Open Access Theses & Dissertations

This study provides new insights into the geometry and timing of ductile, syn-metamorphic structures in the central Panamint Mountains of eastern California. The study focused on Surprise Canyon, where exposures of Meso- to Neoproterozoic miogeocline rocks, reworked crystalline basement, and syn-metamorphic granitoids record fabric overprints indicative of at least two distinct dynamo-thermal metamorphic events. Prograde metamorphism at greenschist and amphibolite metamorphic facies conditions occurred during Early Jurassic plutonism based on deformation of a dioritic pluton with a U-Pb date reported here of 175.6 ± 3.2 Ma. Mid Jurassic deformation (D1) generated the main continuous cleavage in the rocks (S1) as …

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Interactions Of Bacterial Communities With Hydrous Sulfate Minerals In Water-Restricted Gypsic Environments: A Case Study Based In The White Sands National Monument, Brandon Nicholas Lajoie Jan 2019

Interactions Of Bacterial Communities With Hydrous Sulfate Minerals In Water-Restricted Gypsic Environments: A Case Study Based In The White Sands National Monument, Brandon Nicholas Lajoie

Open Access Theses & Dissertations

Microbial communities have been commonly found to survive and thrive in arid to hyper-arid gypsic environments that are considered hostile to most other forms of life. The mechanisms through which microbes have conquered these harsh environments remain poorly understood. Here I hypothesize that the microbial communities in water-restricted gypsic settings could benefit in terms of energy and water sources via their interactions with the abundant hydrous sulfate minerals [i.e., gypsum (CaSO4·2H2O)] that build up these niches. Gypsum is of high bio-relevance because its sulfate component may be used as electron acceptor by sulfate-reducing bacteria and the crystallization water may be …

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Mineral Exploration Investigation In The Northern Sierra Madre Occidental, Mexico, Labdan Nijr Alqahtani Jan 2019

Mineral Exploration Investigation In The Northern Sierra Madre Occidental, Mexico, Labdan Nijr Alqahtani

Open Access Theses & Dissertations

The Sierra Madre region is rich in mineralized deposits, but it is hard to access because of the rugged terrain. Remote sensing and GIS can help in mineral exploration and regional structural analysis. The purpose of this project is to study linear, curvilinear, arcuate, and circular features in the Sierra Madre Occidental of Mexico in order to improve exploration possibility. It is of great interest to know the relationship between lineament intersections, caldera features because of the location of potential mineral occurrences. In this study, 4,445 lineaments were mapped manually using directional filters applied to satellite images. A total of …

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Middle To Late Holocene (7200-2900 Cal. Bp) Archaeological Site Formation Processes At Crumps Sink And The Origins Of Anthropogenic Environments In Central Kentucky, Usa, Justin Nels Carlson Jan 2019

Middle To Late Holocene (7200-2900 Cal. Bp) Archaeological Site Formation Processes At Crumps Sink And The Origins Of Anthropogenic Environments In Central Kentucky, Usa, Justin Nels Carlson

Theses and Dissertations--Anthropology

Though some researchers have argued that the Big Barrens grasslands of Kentucky were the product of anthropogenic land clearing practices by Native Americans, heretofore, this hypothesis had not been tested archaeologically. More work was needed to refine chronologies of fire activity in the region, determine the extent to which humans played a role in the process, and integrate these findings with the paleoenvironmental and archaeological record. With these goals in mind, I conducted archaeological and geoarchaeological investigations at Crumps Sink in the Sinkhole Plain of Kentucky. The archaeological record and site formation history of Crumps Sink were compared with environmental …

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Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang Jan 2019

Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang

Chulalongkorn University Theses and Dissertations (Chula ETD)

ถ่านหินและหินตะกอนจำนวน 31 ตัวอย่างจากแหล่งถ่านหินแม่ตีบและแหล่งถ่านหินแม่ทานที่ตั้งอยู่ในจังหวัดลำปางทางตอนเหนือของประเทศไทยถูกนำมาศึกษาลักษณะเฉพาะทางธรณีเคมีอินทรีย์ (Organic geochemistry) ผลจากการวิเคราะห์ปริมาณสารอินทรีย์ทั้งหมด (Total organic carbon) พบว่าตัวอย่างถ่านหินจากแหล่งแม่ตีบมีค่าระหว่าง 30.12 - 73.71 wt. % และสูงกว่าตัวอย่างถ่านหินของแหล่งแม่ทานซึ่งมีค่าระหว่าง 23.48 - 52.50 wt. % หินดินดานจากทั้งสองแหล่งมีค่าใกล้เคียงกันระหว่าง 4.82 - 19.49 wt. % ในแหล่งแม่ตีบ และ 14.00 - 24.87 wt. % ในแหล่งแม่ทาน ค่าที่น้อยที่สุดของปริมาณสารอินทรีย์ทั้งหมดปรากฏในตัวอย่างหินโคลนซึ่งมีค่าระหว่าง 0.88 – 4.92 wt. % ในแหล่งแม่ตีบ และค่าระหว่าง 0.59 – 5.98 wt. % การวิเคราะห์ปริมาณสารอินทรีย์ที่สกัดได้ (Extractable organic matter) ในตัวอย่างหินของแหล่งแม่ตีบมีค่าระหว่าง 1,277 - 9,764 ppm ในขณะที่ตัวอย่างหินของแหล่งแม่ทานมีค่ามากกว่าโดยอยู่ระหว่าง 1,256-16,421 ppm จากข้อมูลข้างต้นทั้งสองแหล่งมีศักยภาพการเป็นชั้นหินต้นกำเนิดของแหล่งปิโตรเลียมอยู่ในเกณฑ์ดีถึงดีเยี่ยมยกเว้นหินโคลนบางตัวอย่าง ข้อมูลลักษณะเฉพาะทางธรณีเคมีอินทรีย์ศึกษาจากแก๊สโครมาโตแกรม (Gas chromatogram) ได้มาจากการวิเคราะห์โดยใช้เครื่องมือแก๊สโครมาโตกราฟี-แมสสเปกโตมิเตอร์ (Gas chromatography-mass spectrometer) ซึ่งให้ข้อมูลของตัวชี้วัดทางชีวภาพ (Biomarker and non-biomarker) ที่มีประโยชน์ในการตีความทั้งระดับความพร้อมสมบูรณ์ (Maturity) ชนิดของอินทรีย์วัตถุ (Organic matter input) และสภาพแวดล้อมการสะสมตัวในอดีต (Depositional environment) ในการศึกษานี้ถ่านหินมีระดับความพร้อมสมบูรณ์เทียบเคียงกับระดับถ่านหิน (coal rank) อยู่ในระดับลิกไนต์ถึงบิทูมินัสสารระเหยสูงระดับซี (Lignite – high volatile bituminous C) อ้างอิงจากตัวชี้วัดความพร้อมสมบูรณ์ทางชีวภาพ (Biomarker maturity) ซึ่งบ่งชี้ว่าตัวอย่างหินมีระดับความพร้อมสมบูรณ์อยู่ในระดับตอนต้น (immature-early mature stage) แก๊สโครมาโตแกรมของแอลเคนสายตรง (n-alkanes) …

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Research On Land Use Changes And Ecological Risk Assessment In Yongjiang River Basin In Zhejiang Province, China, Peng Tian, Jianlin Li, Hongbo Gong, Ruiliang Pu, Luodan Cao, Shuyao Shao, Zuoqi Shi, Xuili Feng, Lijia Wang, Riuqing Liu Jan 2019

Research On Land Use Changes And Ecological Risk Assessment In Yongjiang River Basin In Zhejiang Province, China, Peng Tian, Jianlin Li, Hongbo Gong, Ruiliang Pu, Luodan Cao, Shuyao Shao, Zuoqi Shi, Xuili Feng, Lijia Wang, Riuqing Liu

School of Geosciences Faculty and Staff Publications

Studying land use changes and ecological risk assessment in Yongjiang River Basin in Zhejiang Province, China, provides theoretical references for optimal configuration of land resources and maintaining stability of ecosystems. Given impacts of land use changes on landscape patterns in the Yongjiang River Basin, ecological risk assessment indexes were constructed and used to analyze temporal and spatial variation characteristics of ecological risk within different periods. Results show that (1) the construction land area was increased quickly, while the cultivated area decreased sharply. A prominent characteristic of land use changes was manifested by transforming cultivated area and forestland into construction land. …

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Use Of Pre-Industrial Baselines To Assess Sources And Pathways Of Metals In Surface Sediment Of Floodplain Lakes In The Peace-Athabasca Delta (Alberta, Canada), Tanner Owca Jan 2019

Use Of Pre-Industrial Baselines To Assess Sources And Pathways Of Metals In Surface Sediment Of Floodplain Lakes In The Peace-Athabasca Delta (Alberta, Canada), Tanner Owca

Theses and Dissertations (Comprehensive)

The effects of natural resources exploitation in northern Canada on downstream aquatic ecosystems is a concern. Assessing these effects requires comprehensive monitoring practices to better inform stakeholders and environmental stewardship decisions. Here, a monitoring approach is developed and applied to assess metals concentrations in lake surface sediments of the Peace-Athabasca Delta (PAD), northern Alberta, Canada. Since the ecological integrity of the PAD is strongly tied to river floodwaters that are critical for replenishing the delta, and the PAD is located downstream of the Alberta oil sands, concerns have been raised over the potential transport of metal contaminants to the PAD …

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Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch Jan 2019

Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch

Theses and Dissertations (Comprehensive)

In the Arctic, winter persists for much of the year, resulting in a hydrological system that is primarily regulated by snow and snowmelt runoff, and has important implications on vegetation, animals, and on the thermal regime of the active layer and permafrost. Snow water equivalent (SWE) measurements such as remote sensing techniques provide coarse resolution data, while snow surveys and snow-pits are labour intensive, have limited spatial coverage and do not provide a continuous reading. Over the last few decades, cosmic ray sensors (CRS) have been proposed as a way to provide much improved snow data, but few studies have …

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High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr Jan 2019

High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr

Theses and Dissertations (Comprehensive)

Arctic tundra environments are characterized by spatially heterogeneous end-of-winter snow cover because of high winds that erode, transport and deposit snow over the winter. This spatially variable end-of-winter snow cover subsequently influences the spatial and temporal variability of snowmelt and results in a patchy snowcover over the melt period. Documenting changes in both snow cover area (SCA) and snow water equivalent (SWE) during the spring melt is essential for understanding hydrological systems, but the lack of high-resolution SCA and SWE datasets that accurately capture micro-scale changes are not commonly available, and do not exist for the Canadian Arctic. This study …

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