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Analysis Of Clastic Cave Sediment In A Fluviokarst System, Russell Cave, Northeast Alabama, Jonathan Camelo Jan 2020

Analysis Of Clastic Cave Sediment In A Fluviokarst System, Russell Cave, Northeast Alabama, Jonathan Camelo

Master's Theses or Doctor of Nursing Practice

Russell Cave is part of a fluviokarst system located along the edge of the Cumberland Plateau in northeast Alabama. The cave system acts as a surface-subsurface drainage system transporting, depositing, and accumulating large influxes of terrestrial-derived materials (sediments, organic material, and magnetic minerals) into the subsurface system forming sediment traps. Five core sites along various discontinuous sediment banks were collected and sampled in 2 cm intervals. Data collection involved Red-Green-Blue (RGB) color, loss on ignition (LOI), magnetic susceptibility (MS) grain-size analysis, end member mixing analysis (EMMA), and 14C radiocarbon dating. The goals for this research were to identify the …

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Weighing The Impacts Of Airbnb In Iceland: Multivariate Perspectives, Alexa Gorlick Jan 2020

Weighing The Impacts Of Airbnb In Iceland: Multivariate Perspectives, Alexa Gorlick

Master's Theses or Doctor of Nursing Practice

This research sought to evaluate if the sharing economy leader, Airbnb, creates impacts that residents of Iceland feel they experience. The study also aimed to discover if rural and urban inhabitants have similar perspectives on Airbnb impacts. Airbnb’s entrepreneurial encroachment into the accommodation sector has caused a multitude of localities to manage an assortment of complex affairs. These matters are difficult to solve due to their changing, contradictory, and incomplete premise. The purpose of this research is to determine if Airbnb activity is prominent in Iceland and therefore causing the country to experience similar issues that officials are struggling to …

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An Expanded Stratigraphic Record Of The Devonian-Carboniferous Boundary Hangenberg Biogeochemical Event From Southeast Iowa (U.S.A.), Brittany M. Stolfus, Bradley D. Cramer, Ryan J. Clark, Nicholas J. Hogancamp, James E. Day, Stephanie A. Tassier-Surine, Brian J. Witzke Jan 2020

An Expanded Stratigraphic Record Of The Devonian-Carboniferous Boundary Hangenberg Biogeochemical Event From Southeast Iowa (U.S.A.), Brittany M. Stolfus, Bradley D. Cramer, Ryan J. Clark, Nicholas J. Hogancamp, James E. Day, Stephanie A. Tassier-Surine, Brian J. Witzke

Faculty Publications - Geography, Geology, and the Environment

The Devonian-Carboniferous boundary in the type area of the Mississippian subsystem (tri-state area of Iowa, Illinois, and Missouri) has been historically difficult to identify. Many of the localities contain similar lithologies and stratigraphic successions, but chronostratigraphic correlation of seemingly identical lithologies can vary greatly in this interval and frequently this has led to miscorrelation. In particular, the similar lithofacies that comprise the McCraney Formation and Louisiana Formation have been a source of stratigraphic confusion for over 100 years. To investigate the Devonian-Carboniferous boundary interval in the Mississippian type area we selected two localities in southeastern Iowa, the H-28 core from …

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Identification Of The Causes And Extent Of Elevated Methane Concentrations In The Groundwater Of Eastern Kentucky, Cristopher Alvarez Villa Jan 2020

Identification Of The Causes And Extent Of Elevated Methane Concentrations In The Groundwater Of Eastern Kentucky, Cristopher Alvarez Villa

Theses and Dissertations--Earth and Environmental Sciences

Recent development of unconventional oil and gas (UOG) resources has prompted concerns about its potential impact on public health and the quality of water and air resources. Elevated dissolved methane concentrations (> 1 mg/L) have been associated with proximity to UOG development and stray gas, but also with natural microbial activity. Baseline gas data, local hydrogeology and geochemistry context can aid assessment of methane sources and interactions. Methane concentrations in eastern Kentucky groundwater are above the “immediate action” level in some private/domestic water wells, show wide variations over small distances, and have been hypothesized to have different relationships to mining. …

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Biogeomorphology Of Bedrock Fluvial Systems: Example From Shawnee Run, Kentucky, Usa, Tasnuba Jerin Jan 2020

Biogeomorphology Of Bedrock Fluvial Systems: Example From Shawnee Run, Kentucky, Usa, Tasnuba Jerin

Theses and Dissertations--Geography

The dynamic interactions between fluvial processes and vegetation vary in different environments and are uncertain in bedrock settings. Bedrock streams are much less studied than alluvial in all aspects, and in many respects act in qualitatively different ways. This research seeks to fill this lacuna by studying bedrock streams from a biogeomorphic perspective. The first part of this research aims to identify the impacts of woody vegetation that may be common to fluvial systems and rocky hillslopes in general, or that may be unique to bedrock channels. A review of the existing literature on biogeomorphology — mostly fluvial and rocky …

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Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love Jan 2020

Assessing The Climate Water Balance Model’S Ability To Predict Soil Moisture Variability And Species Distribution Of A Forested Watershed In The Northern Cumberland Plateau, Katherine J. Love

Theses and Dissertations--Forestry and Natural Resources

Spatial patterns of moisture and tree species have been studied using environmental gradients, often represented by terrain attributes in GIS. With climate change, GIS terrain variables, which are static as long as the elevation remains unchanged, will not reflect alterations in temperature, water cycle, and atmospheric conditions. In this thesis, the commonly used terrain variables and climate water balance variables were evaluated and compared for their ability to explain soil moisture and tree species distributions in a forested watershed in the Northern Cumberland Plateau. The results suggest that GIS terrain variables generally perform better than climate water balance variables, however, …

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A Karst Feature Predictability Model Within Barber County, Kansas, Gary M. Kelner Jan 2020

A Karst Feature Predictability Model Within Barber County, Kansas, Gary M. Kelner

Master's Theses or Doctor of Nursing Practice

This research consisted of two topics: 1) geographic predictive models of karst features and 2), a petrographic study examining the lithology of the study area. The study area is a privately owned ranch in the Gypsum Hills of Barber County, Kansas and is known to have karst features. Two predictive models for karst features were utilized. Previously identified features, Light Detection and Ranging (LiDAR), and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery aided in the creation of these predictive models. These predictability models also used the ESRI ArcMap software platform. The data for these models consists of slope, …

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Fluvio-Karstic Evolution Of The Taşeli Plateau (Central Taurus, Turkey), Muhammed Zeynel Öztürk Jan 2020

Fluvio-Karstic Evolution Of The Taşeli Plateau (Central Taurus, Turkey), Muhammed Zeynel Öztürk

Turkish Journal of Earth Sciences

Uplift history is an important factor in the structural patterns and karstification of the Taşeli Plateau. The morphological development of the study area consists of five stages according to its sedimentation, rotation, uplift, and climatic properties. (1) Shallow carbonates accumulated during the Early Miocene. (2) An emersion and drainage network developed as a result of the compressional neotectonic regime in the Late Miocene. (3) Dense joint systems were formed due to the ~40° clockwise rotation of the eastern limb of the Isparta Angle. (4) The climate of the study area changed as a result of rapid uplift from Late Pliocene …

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Controls On Deep-Water Slope Channel Complex Fill, Propagation, Stacking, Andorientation In The Middle Eocene-Oligocene Kırkgeçit Formation, Elazığ, Eastern Turkey, Hasan Çeli̇k, Bryan Cronin Jan 2020

Controls On Deep-Water Slope Channel Complex Fill, Propagation, Stacking, Andorientation In The Middle Eocene-Oligocene Kırkgeçit Formation, Elazığ, Eastern Turkey, Hasan Çeli̇k, Bryan Cronin

Turkish Journal of Earth Sciences

Deep-water channels are well-exposed along the northern margin of the east-west oriented Late Paleocene to Oligocene Elazığ Basin of eastern Turkey. The deep-water slope channel complexes are characterised by their association with prominent normal faults, where they seem to have controlled their geometries at the northern margin. The channels were fed by coarse-grained sediment shed by subaqueous gravity flows such as high and low-density turbidity currents, and both cohesive and noncohesive debris flows, from elevated hinterland across narrow shelves and through canyons and gullies into the channels. The faulting and subsequent folding along the northern basin margin created a significantly …

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Middle Eocene High-K Acidic Volcanism In The Princes' Islands (İstanbul) And Itsgeodynamic Implications, Fati̇h Şen Jan 2020

Middle Eocene High-K Acidic Volcanism In The Princes' Islands (İstanbul) And Itsgeodynamic Implications, Fati̇h Şen

Turkish Journal of Earth Sciences

The rock assemblages of the Princes? Islands, which are located to the south of mainland İstanbul, are regarded as parts of the Lower Paleozoic quartz sandstones, although they were initially considered as volcanic rocks by Swan in 1868. They differ from quartz sandstones by their vesicular texture and are devoid of any stratigraphic layering. Their mineral constituents are plagioclase (30%-35%), feldspar (35%-40%), and quartz (20%-25%), corresponding to rhyolite. The crystallization age of the rhyolites is 45.66 ± 0.84 Ma on the basis of the U-Pb zircon data. They show high-K calc-alkaline affinity. On primitive-normalized spider diagrams, negative anomalies of Ba, …

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Old And Deer: A Study Of Neoarchean Peridotites In Michigan’S Upper Peninsula, Rachel Merz Jan 2020

Old And Deer: A Study Of Neoarchean Peridotites In Michigan’S Upper Peninsula, Rachel Merz

Senior Honors Theses and Projects

The Deer Lake Peridotite and the Presque Isle Periodotite are two ultramafic formations of Neoarchean age within the Ishpeming Greenstone Belt of Michigan’s Upper Peninsula, and are found only fifteen miles apart. The Deer Lake Peridotite was deformed in processes indicative of the broader, regional-scale tectonics of the region, but little study has been done on the mineralogy and extent and style of alteration. This research aims to better classify the mineralogy of the formation, with particular focus on textural variations observed in thin-section, as well as chemical analysis of samples taken from the formation. In addition, this research seeks …

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Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison Jan 2020

Geochemical Flux Analysis Of Glacial River Runoff For Sólheimajökull, Iceland, Jessica Garrison

Mahurin Honors College Capstone Experience/Thesis Projects

Geochemical fluxes in aqueous studies are an essential component of research to understand weathering and changes in a hydrologic system. These data can indicate any discrepancies, outliers, or gradual changes in a water environment to gain information on pollutants, carbon cycles, biological input, etc. Glacial melt is the majority of the surface water present throughout the country. The melting amount is increasing with the temperatures, which can be monitored by the changes in geochemical flux during increased discharge in glacial rivers. A high-resolution data set of Sόlheimajökull Glacier in Iceland was used to determine how changing climatic conditions for the …

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Earth News, V43, Winter 2020, University Of Northern Iowa. Department Of Earth And Environmental Sciences. Jan 2020

Earth News, V43, Winter 2020, University Of Northern Iowa. Department Of Earth And Environmental Sciences.

Earth News

Inside this issue:
--From the Department Head
--Faculty Updates
--Staff Updates
--SGE Chapter News
--Outreach-Global Visit
--Student Recognition
--Sunday at the Quarry
--Student Spotlights
--Student Research
--50th Anniversary
--Alumni Updates
--Homecoming 2019
--Gifts from Alumni & Friends
--Contribution Form

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Sampling The Local Fare: Fishes At The Sam Israel House Pit (45gr76), Soap Lake, Washington, Adam Fruge Jan 2020

Sampling The Local Fare: Fishes At The Sam Israel House Pit (45gr76), Soap Lake, Washington, Adam Fruge

All Master's Theses

The Sam Israel site is a precontact archaeological complex with numerous fish bones at the north end of Soap Lake, Washington. Excavated in 1976, the fish remains recovered from there were never fully analyzed prior to this research. Since this inland Columbia Plateau site had thousands of fish bones, it contained untapped potential for our understanding of ancient local fish procurement. As such, I conducted a detailed analysis of 2,862 fish bone specimens from the Sam Israel House Pit locus to: study a larger sample of fish bones in greater detail than was done before; compare the distribution of fishes …

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Evaluation Of The Relationship Between Land Use And Water Quality In Kittitas County, Wa, Lindsay Schulz Jan 2020

Evaluation Of The Relationship Between Land Use And Water Quality In Kittitas County, Wa, Lindsay Schulz

All Master's Theses

Water in Kittitas County is extremely valuable since it supports farming, recreation, and cultural activities, as well as environmental processes and a diversity of biological life while providing many ecosystem services. However, land conversions required by agricultural and urban land uses can negatively impact water quality and the biological function of the stream. I studied how forested, agricultural, and urban land use affect six streams. Fourteen sites were sampled, once each in July, August, and September 2019. Land use was calculated as a percentage of forested, agricultural, and urban land use within a 100-m buffer of the stream, upstream of …

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Glaciernet: A Deep-Learning Approach For Debris-Covered Glacier Mapping, Zhiyuan Xie, Umesh K. Haritashya, Vijayan K. Asari, Brennan W. Young, Michael P. Bishop, Jeffrey S. Kargel Jan 2020

Glaciernet: A Deep-Learning Approach For Debris-Covered Glacier Mapping, Zhiyuan Xie, Umesh K. Haritashya, Vijayan K. Asari, Brennan W. Young, Michael P. Bishop, Jeffrey S. Kargel

Electrical and Computer Engineering Faculty Publications

Rising global temperatures over the past decades is directly affecting glacier dynamics. To understand glacier fluctuations and document regional glacier-state trends, glacier-boundary detection is necessary. Debris-covered glacier (DCG) mapping, however, is notoriously difficult using conventional geospatial technology methods. Therefore, in this research for automated DCG mapping, we evaluate the utility of a convolutional neural network (CNN), which is a deep learning feed-forward neural network. The CNN inputs include Landsat satellite images, an Advanced Land Observation Satellite (ALOS) digital elevation model (DEM) and DEM-derived land-surface parameters. Our CNN based deep-learning approach named GlacierNet was designed by appropriately choosing the type, number …

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Evaluating Cmip6 Model Fidelity At Simulating Non-Gaussian Temperature Distribution Tails, Arielle J. Catalano, Paul Loikith, J. David Neelin Jan 2020

Evaluating Cmip6 Model Fidelity At Simulating Non-Gaussian Temperature Distribution Tails, Arielle J. Catalano, Paul Loikith, J. David Neelin

Geography Faculty Publications and Presentations

Under global warming, changes in extreme temperatures will manifest in more complex ways in locations where temperature distribution tails deviate from Gaussian. Confidence in global climate model (GCM) projections of temperature extremes and associated impacts therefore relies on the realism of simulated temperature distribution tail behavior under current climate conditions. This study evaluates the ability of the latest state-of-the-art ensemble of GCMs from the Coupled Model Intercomparison Project phase six (CMIP6), to capture historical global surface temperature distribution tail shape in hemispheric winter and summer seasons. Comparisons with a global reanalysis product reveal strong agreement on coherent spatial patterns of …

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Glacial Deposits, Vol. 45, 2020, Department Of Geography, Geology, And The Environment Jan 2020

Glacial Deposits, Vol. 45, 2020, Department Of Geography, Geology, And The Environment

Glacial Deposits

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

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Geology And Aquifer Sensitivity Of Quaternary Glacial Deposits Overlying A Portion Of The Mahomet Buried Bedrock Valley Aquifer System, Andrew Watson, Eric W. Peterson, Dave Malone, Lisa Tranel Jan 2020

Geology And Aquifer Sensitivity Of Quaternary Glacial Deposits Overlying A Portion Of The Mahomet Buried Bedrock Valley Aquifer System, Andrew Watson, Eric W. Peterson, Dave Malone, Lisa Tranel

Faculty Publications - Geography, Geology, and the Environment

To characterize the distribution of Holocene and Late Quaternary deposits and to assess the contamination potential of the Mahomet Aquifer, surficial geologic and aquifer sensitivity maps of the Gibson City East 7.5-Minute Quadrangle were created. Geologic data, extent, and thickness of the geologic materials were coupled with LiDAR topographic data and analyzed using ESRI’s ArcGIS 10.6.1. Aquifer sensitivity to contamination was calculated based on the depth to the first aquifer unit, aquifer thickness, and the lithology of the aquifer materials. The surficial geologic mapping identified five lithostratigraphic units: the Cahokia Formation, the Equality Formation, the Henry Formation, and the Yorkville …

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The Impacts Of Accessibility On Vulnerability Of Place In Comfort Castle, Jamaica, Heather Thole Jan 2020

The Impacts Of Accessibility On Vulnerability Of Place In Comfort Castle, Jamaica, Heather Thole

Dissertations, Master's Theses and Master's Reports

Jamaica experiences meteorological, hydrological, and geological natural hazards that can produce island-wide impacts. The island’s exposure to multiple hazard types requires effective and sustainable mitigation and disaster risk management to lessen potential impacts, especially for vulnerable populations and communities. Comfort Castle, a small rural farming community, sits in the upper Rio Grande Valley of Portland parish and experiences earthquakes, landslides, hurricanes, heavy rainfall, and floods. Steep terrain and remoteness due to geographic location affect the community’s geophysical vulnerability. Their social vulnerability results from a lack of employment, health, educational, and livelihood resources within the community. Together, geophysical, and social factors …

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3d Surface Modeling Of Late Pleistocene Glaciers In The Munzur Mountains(Eastern Turkey) And Its Paleoclimatic Implications, Zeynel Çilğin Jan 2020

3d Surface Modeling Of Late Pleistocene Glaciers In The Munzur Mountains(Eastern Turkey) And Its Paleoclimatic Implications, Zeynel Çilğin

Turkish Journal of Earth Sciences

Located in the Eastern Anatolian Region in Turkey, the Munzur Mountains (Munzurs; 3463 m above sea level) are one of the most important glacial landscapes in Turkey, with evidence for extensive glaciations in the past and small-scale glaciation at present. As Turkey's second-largest glaciated region, these mountains include various glacial landforms, primarily glacial valleys, hanging valleys, cirques, and moraines. However, only limited data are available on the extent and chronology of former glaciations in the Munzur Mountains. This study produced data on the extent of paleoglaciers, calculated their equilibrium line altitudes (ELAs), revealed paleoclimate conditions, and modeled paleo temperatures during …

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Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz Jan 2020

Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

High-elevation tropical lakes are excellent sentinels of global change impacts, such as climate warming, land-use change, and atmospheric deposition. These effects are often correlated with temporal and spatial beta diversity patterns, with some local communities contributing more than others, a phenomenon known as local contribution to beta diversity (LCBD) or ecological uniqueness. Microorganisms, such as diatoms, are considered whole-ecosystem indicators, but little is known about their sensitivity and specificity in beta diversity studies mostly because of the lack of large spatial and temporal datasets. To fill this gap, we used a tropical South American diatom database comprising modern (144 lakes) …

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End-Permian (252 Mya) Deforestation, Wildfires And Flooding—An Ancient Biotic Crisis With Lessons For The Present, Vivi Vajda, Stephen Mcloughlin, Chris Mays, Tracy D. Frank, Christopher R. Fielding, Allen Tevyaw, Veiko Lehsten, Malcolm Bocking, Robert S. Nicoll Jan 2020

End-Permian (252 Mya) Deforestation, Wildfires And Flooding—An Ancient Biotic Crisis With Lessons For The Present, Vivi Vajda, Stephen Mcloughlin, Chris Mays, Tracy D. Frank, Christopher R. Fielding, Allen Tevyaw, Veiko Lehsten, Malcolm Bocking, Robert S. Nicoll

Department of Earth and Atmospheric Sciences: Faculty Publications

Current large-scale deforestation poses a threat to ecosystems globally, and imposes substantial and prolonged changes on the hydrological and carbon cycles. The tropical forests of the Amazon and Indonesia are currently undergoing deforestation with catastrophic ecological consequences but widespread deforestation events have occurred several times in Earth’s history and these provide lessons for the future. The end-Permian mass-extinction event (EPE; ∼252 Ma) provides a global, deep-time analogue for modern deforestation and diversity loss. We undertook centimeter-resolution palynological, sedimentological, carbon stable-isotope and paleobotanical investigations of strata spanning the end- Permian event at the Frazer Beach and Snapper Point localities, in the …

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Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard Jan 2020

Interpretive Geologic Maps And Cross Sections For Phelps, Kearney, And Adams Counties In Nebraska, Dana Divine, Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

Data from thousands of test-hole and well logs were interpreted to improve understanding and management of the High Plains aquifer in a three-county study area adjacent to the Big Bend reach of the Platte River. Five principal conclusions resulted from these interpretations: (1) the extent of Neogene Ogallala deposits beneath the study area is different than previously mapped; (2) a large paleovalley incised into Cretaceous bedrock probably cuts across Kearney and Adams counties and may be the course of the ancestral Platte River prior to formation of the Big Bend; (3) a groundwater mound created by irrigation canals artificially raises …

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Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons Jan 2020

Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons

United States Geological Survey: Staff Publications

In 1979, S. Uyeda and H. Kanamori proposed a tectonic model with two end members of a subduction-boundary continuum: the “Chilean” type (shallow dip of the subducting plate, great thrust events, compression, and uplift of the overriding plate) and a “Mariana” type (steep dip of the subducting plate, no great thrust events, tension, and no uplift). This concept has been used to explain variable rates of Quaternary uplift around the Pacific Rim, yet no uplift rates have been determined for the Mariana Islands themselves, one of the end members in this model. We studied the late Quaternary Tanapag Limestone, which …

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Characterizing The Hydrological Function Of Treed Bogs In The Zone Of Discontinuous Permafrost, Brenden Disher Jan 2020

Characterizing The Hydrological Function Of Treed Bogs In The Zone Of Discontinuous Permafrost, Brenden Disher

Theses and Dissertations (Comprehensive)

The loss of permafrost has produced a wholesale conversion from forest to wetland, and many studies have analyzed the effects of permafrost thaw-induced land cover change on the hydrology and ecology of landscapes within the Taiga Plains. The permafrost thaw driven areal shrinkage of forested plateaux and their replacement by treeless wetlands is well documented, and the co-occurrence of permafrost and black spruce forest cover is the basis for areal estimates of the former. However, field studies conducted at a peatland dominated landscape near Fort Simpson, NWT indicate that tree canopy may persist following the loss of permafrost and the …

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Investigating Diel, Seasonal, And Interannual Variability Of Dissolved And Particulate Stable Carbon Isotope Values In A Eutrophic Boreal Lake, Rachel Henderson Jan 2020

Investigating Diel, Seasonal, And Interannual Variability Of Dissolved And Particulate Stable Carbon Isotope Values In A Eutrophic Boreal Lake, Rachel Henderson

Theses and Dissertations (Comprehensive)

Lakes are globally significant sources, sinks, and conduits of carbon. Cultural eutrophication of freshwater promotes the growth of phytoplankton blooms, which can transform, respire, and sequester large amounts of carbon. Analysis of stable carbon isotopes is a common tool to study the movement of carbon through the aquatic carbon cycle. The causes of temporal variability in δ13C values at different timescales are not well understood, and differ between lakes. In this study, I investigated diel, seasonal, and interannual variability in δ13C values of dissolved inorganic carbon (DIC) and particulate organic carbon (POC) in Lake 227, an …

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The Effect Of Spacing Of Vetiver Grass (Chrysopogon Zizanioides) Hedgerows On Hillslope Erosion In Eastern Region, Ghana, Evan R. Lanese Jan 2020

The Effect Of Spacing Of Vetiver Grass (Chrysopogon Zizanioides) Hedgerows On Hillslope Erosion In Eastern Region, Ghana, Evan R. Lanese

Dissertations, Master's Theses and Master's Reports

Soil erosion in Ghana negatively effects many small holder farmers due to heavy rainfall, continuous land use, and a changing climate. Inexpensive, local, and sustainable practices that can be used to reduce soil movement thus building productive soils would benefit farmers in Ghana. Vetiver grass (Chrysopogon zizanioides) has been used to this effect worldwide. Its local availability and positive reputation leaves desire to learn about its applicability in Ghana. A field study was conducted on plots of sloping farmland (10ft by 60ft) with three treatments: (1) control with no vetiver grass, (2) two vetiver grass hedgerows, (3) four …

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Understanding And Measuring Net Positive Business Strategies, Luke Ruffner Robinson Jan 2020

Understanding And Measuring Net Positive Business Strategies, Luke Ruffner Robinson

Graduate Student Theses, Dissertations, & Professional Papers

Despite their attempts to mitigate ecological impacts through sustainability initiatives, businesses are a major cause of the world's ecological problems. Some progressive businesses are attempting to move beyond “net zero” in terms of achieving neutral environmental impacts and instead are now pursuing a goal of net positive. Net positive refers to the idea that business activities could contribute value-added benefits to earth’s ecological systems, for example, by using technologies that sequester and store carbon. However, except for a handful of high-profile corporate case studies, little is known about how companies are developing their strategies to become net positive and …

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Active Seismic Studies In Lemon Creek Valley Glacier, Juneau, Alaska: Characterization Of Subglacial Sediments To Understand Glacier Dynamics, Lucia Fernanda Gonzalez Jan 2020

Active Seismic Studies In Lemon Creek Valley Glacier, Juneau, Alaska: Characterization Of Subglacial Sediments To Understand Glacier Dynamics, Lucia Fernanda Gonzalez

Open Access Theses & Dissertations

Deformation and flow properties of subglacial sediments as well as the presence and volume of water at the ice/bed interface strongly influence glacier dynamics. Studies of Lemon Creek Glacier, a small temperate valley glacier in the Juneau Icefield, near Juneau, Alaska, have shown that the glacier is rapidly retreating, with a negative mass balance every year since 1957. However, the bed topography and properties of subglacial sediments at the base of Lemon Creek Glacier remained unknown until now. In this project, we process and interpret ~1-km-long NW-SE trending active-source seismic reflection profiles collected during June and July 2017 near the …

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