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Strange Stones Of Skull Creek: Basalt Glacial Erratics And Omars In Eastern Nebraska, Robert M. Joeckel, Jesse T. Korus, Judith Turk, C. C. Arps, N. V. Arps, Leslie M. Howard 2022 University of Nebraska-Lincoln

Strange Stones Of Skull Creek: Basalt Glacial Erratics And Omars In Eastern Nebraska, Robert M. Joeckel, Jesse T. Korus, Judith Turk, C. C. Arps, N. V. Arps, Leslie M. Howard

Conservation and Survey Division

We describe unusual stream- reworked glacially transported rocks (erratics) from a locality 50 km east of the limit of all pre- Illinoian (pre- 190 ka) Pleistocene glaciations in the central USA. Almost all these erratics consist of the igneous rock basalt, and of those, the vast majority have at least one fl at, smooth face. Some have two or more such faces that meet at obtuse angles along one or more well- defi ned, straight edges. We attribute these features, as well as laminations, plumose marks, and other features, to columnar jointing in ancient lava fl ows and shallow intrusions. …


Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok 2022 Wilfrid Laurier University

Coastal Landform Change Influences On Endangered Five-Lined Skink Distribution At Northwest Beach, Point Pelee National Park, Canada, Evan Fortushniok

Theses and Dissertations (Comprehensive)

As park visitation increased to Point Pelee National Park up until its peak in 1963, the installation of infrastructure for the purpose of supporting the recreational interest grew with it. At Northwest Beach, large parking lots were built into the coastal landscape and by the 1970s large areas of sand dunes continued to be heavily impacted by the installation of visitor associated infrastructure. The infrastructure resulted in the stabilization of sand on the beach side of the parking lot, resulting in an artificially stabilized and heavily vegetated dune. Over the last few decades, the park slowly reduced the size and …


Hydrogeomorphic Response Of Steep Streams Following Severe Wildfire In The Western Cascades, Oregon, David Matthew Busby 2022 University of Montana

Hydrogeomorphic Response Of Steep Streams Following Severe Wildfire In The Western Cascades, Oregon, David Matthew Busby

Graduate Student Theses, Dissertations, & Professional Papers

Severe wildfire may alter the morphologic resilience of steep mountain streams by increasing peak discharges, elevating inputs of sediment and wood into channels, and increasing susceptibility to landslides and debris flows. In the Pacific Northwest, where mean annual precipitation is high and mean fire return intervals range from decades to centuries, understanding of steep stream response to fire is limited. In 2020, the Western Cascade Range, Oregon, experienced wildfire of historic magnitude and severity. The objective of this study was to evaluate the hydrologic and geomorphic response of steep streams to the 2020 fires. I assessed streamflow, instream wood, and …


Development Of Regional Landslide Susceptibility Models: A First Step Towards Model Transferability, Gina M. Belair 2022 University of Montana, Missoula

Development Of Regional Landslide Susceptibility Models: A First Step Towards Model Transferability, Gina M. Belair

Graduate Student Theses, Dissertations, & Professional Papers

Landslides are a globally pervasive problem with the potential to cause significant fatalities and economic losses. Although landslides are widespread, many at-risk regions may not have the high-quality data or resources used in most landslide susceptibility analyses. This study aims to develop regional susceptibility relationships that are versatile and use publicly available data and open-sourced software. Logistic Regression and Frequency Ratio susceptibility relationships were developed in 23 regions in Washington, Utah, North Carolina, and Kentucky, with a region referring to a unique area and data combination. Regions were diverse in their geology, morphology, climate, and nature and quality of their …


Fine Scale Mapping Of Laurentian Mixed Forest Natural Habitat Communities Using Multispectral Naip And Uav Datasets Combined With Machine Learning Methods, Parth P. Bhatt 2022 Michigan Technological University

Fine Scale Mapping Of Laurentian Mixed Forest Natural Habitat Communities Using Multispectral Naip And Uav Datasets Combined With Machine Learning Methods, Parth P. Bhatt

Dissertations, Master's Theses and Master's Reports

Natural habitat communities are an important element of any forest ecosystem. Mapping and monitoring Laurentian Mixed Forest natural communities using high spatial resolution imagery is vital for management and conservation purposes. This study developed integrated spatial, spectral and Machine Learning (ML) approaches for mapping complex vegetation communities. The study utilized ultra-high and high spatial resolution National Agriculture Imagery Program (NAIP) and Unmanned Aerial Vehicle (UAV) datasets, and Digital Elevation Model (DEM). Complex natural vegetation community habitats in the Laurentian Mixed Forest of the Upper Midwest. A detailed workflow is presented to effectively process UAV imageries in a dense forest environment …


Evidence For Metabolic Diversity In Meso-Neoproterozoic Stromatolites (Vazante Group, Brazil), Flavia Callefo, Fresia Ricardi-Branco, Mirian Mírian Liza Alves Forancelli Pacheco, Alexandre Ribeiro Cardoso, Nora Noffke, Verônica de Carvalho Teixeira, Itamar Tomio Neckel, Lara Maldanis, Emma Bullock, Dina Bower, Adalene Moreira Silva, Dario Ferreira Sanchez, Fabio Rodrigues, Douglas Galante 2022 Old Dominion University

Evidence For Metabolic Diversity In Meso-Neoproterozoic Stromatolites (Vazante Group, Brazil), Flavia Callefo, Fresia Ricardi-Branco, Mirian Mírian Liza Alves Forancelli Pacheco, Alexandre Ribeiro Cardoso, Nora Noffke, Verônica De Carvalho Teixeira, Itamar Tomio Neckel, Lara Maldanis, Emma Bullock, Dina Bower, Adalene Moreira Silva, Dario Ferreira Sanchez, Fabio Rodrigues, Douglas Galante

OES Faculty Publications

Deciphering the evolution of ecological interactions among the metabolic types during the early diversification of life on Earth is crucial for our understanding of the ancient biosphere. The stromatolites from the genus Conophyton cylindricus represent a datum for the Proterozoic (Meso to Neoproterozoic) on Earth. Their typical conical shape has been considered a result of a competition between microorganisms for space, light and nutrients. Well-preserved records of this genus from the "Paleontological Site of Cabeludo ", Vazante Group, São Francisco Craton (Southern Brazil) present in situ fossilized biofilms, containing preserved carbonaceous matter. Petrographic and geochemical analyses revealed an alternation between …


Reconstructing Regional Paleoenvironments And Geomorphic History Of High Plains Playa-Lunette Systems, Alyssa E. Sims 2022 Minnesota State University, Mankato

Reconstructing Regional Paleoenvironments And Geomorphic History Of High Plains Playa-Lunette Systems, Alyssa E. Sims

All Graduate Theses, Dissertations, and Other Capstone Projects

Playas are ephemeral upland-embedded wetlands found in semiarid and arid regions worldwide. Lunettes are isolated dunes that form along the downwind margin of playas. The paleoclimatic and geomorphic history of High Plains playa-lunette systems (PLSs) are poorly understood. To address this, we characterize the stratigraphy of four PLSs in southwest Kansas, USA. Methods include: 1) collect soil-sediment cores from playa centers and windward slopes of lunettes; 2) describe cores using USDA techniques; 3) estimate age of stratigraphic units using radiocarbon (14C); and 4) reconstruct paleoenvironmental conditions using stable carbon isotopes (13C) and particle size analysis. Playa stratigraphy is relatively simple …


Geomorphic History And Preservation Of Archaeologically Significant Areas In The Hanford Reach Of The Columbia River, Washington State, Benjamin Deans 2022 Central Washington University

Geomorphic History And Preservation Of Archaeologically Significant Areas In The Hanford Reach Of The Columbia River, Washington State, Benjamin Deans

All Master's Theses

Archaeological sites near rivers may be preserved through burial, altered by exposure, or destroyed through erosion. Preserved because of the unusual needs of the Manhattan Project, the Hanford Reach is the only remaining free-flowing reach of the Columbia River and ideal for research into the geomorphic settings of archaeological sites along this river. The 1894 (742,000 cfs [20,900 m3/s]) and 1948 (690,000 cfs [19,000 m3/s]) floods were the largest in the historical record through the reach, but their relationship with geomorphic change and site preservation are less understood. To understand how floods have preserved and destroyed …


Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett 2022 Central Washington University

Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett

All Master's Theses

Numerous stream restoration projects in the Yakima River Basin in Washington have placed large wood (LW) into tributary channels. One intended effect is to divert water onto floodplains to increase groundwater (GW) recharge and seasonal storage in shallow alluvial aquifers during spring high flows with the intention of releasing GW into streams during the drier summer months. Large wood was emplaced in the Indian Creek tributary of the Teanaway River in Kittitas County, Washington beginning in 2016. Potential changes in the groundwater recharge in the adjacent floodplain before and after the LW installation were investigated through stratigraphic analysis, stream-flow modeling, …


Decadal-Scale Effects Of Large Wood Restoration On Channel Morphology And Groundwater Connectivity, Taneum Creek, Wa, Samuel Fixler 2022 Central Washington University

Decadal-Scale Effects Of Large Wood Restoration On Channel Morphology And Groundwater Connectivity, Taneum Creek, Wa, Samuel Fixler

All Master's Theses

The importance of large wood (LW) in creating channel complexity is widely recognized; however, few LW projects have been in place long enough to track meaningful channel changes on a decadal timescale. Taneum Creek, located in central Washington, is one of the earliest LW restoration areas (2008) in the Yakima River Basin and the central Cascade Mountains. The flood in 2011, with an estimated discharge of 69 m3/s (2,400-2,800 cfs), provided further channel change by mobilizing LW and channel sediments. Three reaches with similar channel characteristics and LW additions were compared with a control reach without LW additions …


Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton 2021 University of Arkansas, Fayetteville

Analysis Of Titan's Fluvial Features Using Numerical Modeling, Jeshurun Horton

Mechanical Engineering Undergraduate Honors Theses

River channels have been observed near the Huygens probe landing site on the surface of Titan, along with evidence of rounded water ice boulders transported through fluid flow. Evidence near the landing site suggests active flow of liquid methane, which has motivated the study of the effects of sediment load and channel sizes on Titan’s fluvial features. A numerical model is used to determine the viscosity, flow velocity, and critical boulder transport diameter based on channel size, slope, and a range of sediment concentrations. This model achieves two ends: first, observed boulder diameters are used to determine the ideal channel …


A Connectivity Framework To Explore The Role Of Anthropogenic Activity And Climate On The Propagation Of Water And Sediment At The Catchment Scale, Christos Giannopoulos 2021 University of Tennessee, Knoxville

A Connectivity Framework To Explore The Role Of Anthropogenic Activity And Climate On The Propagation Of Water And Sediment At The Catchment Scale, Christos Giannopoulos

Doctoral Dissertations

Anthropogenic disturbance in intensively managed landscapes (IMLs) has dramatically altered critical zone processes, resulting in fundamental changes in material fluxes. Mitigating the negative effects of anthropogenic disturbance and making informed decisions for optimal placement and assessment of best management practices (BMPs) requires fundamental understanding of how different practices affect the connectivity or lack thereof of governing transport processes and resulting material fluxes across different landscape compartments within the hillslope-channel continuum of IMLs. However, there are no models operating at the event timescale that can accurately predict material flux transport from the hillslope to the catchment scale capturing the spatial and …


Fine Grained Delta Front Sediment Transport, Sarah Noel 2021 University of New Orleans, New Orleans

Fine Grained Delta Front Sediment Transport, Sarah Noel

University of New Orleans Theses and Dissertations

Insights into transformative coastal processes are unlocked though understanding sediment transport mechanisms in fine-grained delta front environments. Movement of fine-grained sediments on delta fronts is not wholly explained through advection settling models. While advection settling models generally assume deposition into a still body, numerical modeling of sediment re-entrainment suggests there may be tidal, wave, and/or non-steady hydrograph influences allowing particles to reach greater distances by altering the decelerating velocity field. This research explores both an advection settling model and a mass conservation Rouse profile model to understand the irreducible delta front processes controlling sediment deposition. Using field data collected on …


Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr 2021 Slovak Caves Administration, Liptovský Mikuláš, Slovakia

Speleogenesis In A Lens Of Metamorphosed Limestone And Ankerite: Ochtiná Aragonite Cave, Slovakia, Pavel Bella, Pavel Bosák, Petr Pruner, Helena Hercman, Katarína Pukanská, Karol Bartoš, Ľudovít Gaál, Dagmar Haviarová, Peter Tomčík, Šimon Kdýr

International Journal of Speleology

The Ochtiná Aragonite Cave (Western Carpathians) represents an unique natural phenomenon. It originated under particular lithological and hydrogeological conditions of the Ochtiná Karst in which several isolated lenses of Paleozoic crystalline limestone (marbles), partly metasomatically altered to ankerite, are enclosed by phyllites. Meteoric water seepage through non-carbonate rocks dissolved limestone and caused the oxidation of ankerite to Fe oxyhydroxides. Carbon dioxide produced during ankerite oxidation enhanced limestone dissolution. The maze cave consists of parallel fault-controlled linear passages and chambers interconnected by transverse horizontal passages. Phreatic and epiphreatic solution morphologies resulted from slowly moving or standing water. These include flat ceilings …


Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings 2021 Portland State University

Silica Sinter And The Evolution Of Hot Springs In The Alvord/Pueblo Valleys, Southeast Oregon, Usa, Leslie Allen Mowbray, Michael L. Cummings

Geology Faculty Publications and Presentations

Hot springs in the Alvord/Pueblo valleys in southeastern Oregon are analogous to Basinand- Range hydrothermal systems where heat source and permeable pathways are met through crustal thinning. Silica sinter deposition at Mickey Springs, Alvord Valley, predates the late Pleistocene high stand of pluvial Lake Alvord. At Borax Lake, Pueblo Valley, sinter deposition occurred during the Holocene. This study examines the evolution of springs at Mickey Springs, where three morphologies of sinter are present: (1) basalt clasts surrounded by sinter in interbedded conglomerate and sandstone, (2) pool-edge and aprons of sinter surrounding depressions (12–32 m diameter), and (3) quaquaversal sinter mounds …


The Importance Of Lithologic Variability And Stratigraphic Architecture In The Development Of Eogenetic Karst Systems, Nicholas J. Soto-Kerans 2021 University of South Florida

The Importance Of Lithologic Variability And Stratigraphic Architecture In The Development Of Eogenetic Karst Systems, Nicholas J. Soto-Kerans

USF Tampa Graduate Theses and Dissertations

Integrative characterizations of karst systems on low-lying eogenetic carbonate platforms are rare and often limited to areas of direct observation where caves can be entered and explored. Because hydraulic properties of eogenetic limestones have been implicitly assumed to be homogeneous, classical models of carbonate island karst development stressed the importance of geochemical interfaces in controlling cave and vug development. These studies have explained the largest cavern systems as results of either 1) mixing dissolution at platform margins or 2) microbially-mediated dissolution processes at water tables.

New data from core descriptions and wireline logs obtained in 18 boreholes drilled in the …


Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam 2021 University of South Florida

Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam

USF Tampa Graduate Theses and Dissertations

Barrier islands shield the mainland coast from the effects of extreme storms such as increased wave energy and storm surge. During these events, however, barrier morphology can be altered by erosive forces. Thus, compromising the protection offered and leading to increased impact on the mainland. The St. Joseph Peninsula, located in the Northwest of the Gulf of Mexico, is one such barrier at threat from storm-induced erosion. Presented here is an assessment of morphology change induced by two major storms to impact the peninsula, Hurricanes Dennis 2005 and Michael 2018. These changes characterize the erosive/depositional patterns that can be expected …


Short-Term Slope Changes On Dokdo Island Identified From Ground-Based 3d Lidar Data, Jihyun Kang, Hyejin Kim, Jaegeum Park, Hyunchul Shin 2021 National institute of ecology

Short-Term Slope Changes On Dokdo Island Identified From Ground-Based 3d Lidar Data, Jihyun Kang, Hyejin Kim, Jaegeum Park, Hyunchul Shin

International Journal of Geospatial and Environmental Research

This study was designed to determine the slope changes on Dokdo Island, focusing on Seodo islet (slopes consisting of colluvial debris) and Dongdo islet (slopes consisting of large-scale tafoni). To do so, we obtained high-resolution 3D LiDAR data in May and November 2020 and calculated the changes in slope shape and volume over this period. Our results showed that during this time, approximately 136 m3 of colluvial debris was removed from the slopes of Seodo islet and a boulder that had separated from the massive tuff breccia migrated approximately 5 cm downslope. The major causes of such rapid changes …


Magnitude And Rates Of Agriculturally-Induced Soil Erosion In The Midwestern United States, Evan Thaler 2021 University of Massachusetts Amherst

Magnitude And Rates Of Agriculturally-Induced Soil Erosion In The Midwestern United States, Evan Thaler

Doctoral Dissertations

Fertile, agricultural productive soils are essential for producing food for a growing global population. Soil erosion diminishes soil quality, threatens food security by decreasing crop productivity, and degrades ecosystem health through increased rates of sedimentation and runoff. Despite decades and thousands of soil erosion studies, robust scalable methods for estimating the magnitude and rates of soil erosion have been elusive. In this dissertation, we develop a remote sensing method for quantifying the areal extent of historical loss in an agricultural landscape and provide a method for estimating the total thickness of soil loss and rates of historical soil loss in …


Sedimentary Processes Influencing Divergent Wetland Evolution In The Hudson River Estuary, Kelly McKeon 2021 University of Massachusetts Amherst

Sedimentary Processes Influencing Divergent Wetland Evolution In The Hudson River Estuary, Kelly Mckeon

Masters Theses

Consistent shoreline development and urbanization have historically resulted in the loss of wetlands. However, some construction activities have inadvertently resulted in the emergence of new tidal wetlands, with prominent examples of such anthropogenic wetlands found within the Hudson River Estuary. Here, we utilize two of these human-induced tidal wetlands to explore the sedimentary and hydrologic conditions driving wetland development from a restoration perspective. Tivoli North Bay is an emergent freshwater tidal marsh, while Tivoli South Bay is an intertidal mudflat with vegetation restricted to the seasonal growth of aquatic vegetation during summer months. Using a combination of sediment traps, cores, …


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