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Full-Text Articles in Earth Sciences

Geomorphology And Chronology Of Sand Stringer Deposition Beyond The Ice Margin: Southeastern Minnesota And Western Wisconsin, Usa, Richard J. Mataitis Jan 2020

Geomorphology And Chronology Of Sand Stringer Deposition Beyond The Ice Margin: Southeastern Minnesota And Western Wisconsin, Usa, Richard J. Mataitis

All Graduate Theses, Dissertations, and Other Capstone Projects

The purpose of this Master’s thesis is to investigate linear, aeolian deposits termed “sand stringers” located within western Wisconsin and southeastern Minnesota. Previous research has investigated their spatial distribution, and to a minor extent, their composition and absolute age. However, further sedimentological and absolute age data are needed from a greater distribution of sand stringers to understand their formation and depositional chronology. To build on previous research we 1) remotely mapped the spatial distribution and orientation of sand stringers in western Wisconsin and southeastern Minnesota, 2) collected absolute age data using optically stimulated luminescence (OSL) from four stringers in western …


Tidal-Groundwater Study Of The Slaughter Beach Salt Marsh In Slaughter Beach, De, Michael Powers Jan 2020

Tidal-Groundwater Study Of The Slaughter Beach Salt Marsh In Slaughter Beach, De, Michael Powers

West Chester University Master’s Theses

Seasonal and decadal monitoring of salt marsh at Slaughter Beach, DE documented long-term and short-term variations in number and sizes of salt ponds. Over 400 salt ponds ranging in size between 0.5 m2 to 0.11 km2 were identified on 5.5 km2 salt marsh platform. The purpose of this study is to quantify hydrologic conditions and measure groundwater discharge of a salt marsh, particularly the impact of tidal forces on groundwater fluctuation.

Four wells with nests of mini-piezometers with ONSET Pressure Transducers were installed along a transect crossing the largest salt pond (0.11 km2) in the …


Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. Mcguire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch Jan 2020

Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. Mcguire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch

United States Geological Survey: Publications

The Mississippi River Valley alluvial (MRVA) aquifer is an important surficial aquifer in the Mississippi Alluvial Plain (MAP) area. The aquifer is generally considered to be an unconfined aquifer (fig. 1; Clark and others, 2011), and withdrawals are primarily used for irrigation (Maupin and Barber, 2005). These groundwater withdrawals have resulted in substantial areas of water-level decline in parts of the aquifer. Concerns about water-level declines and the sustainability of the MRVA aquifer have prompted the U.S. Geological Survey (USGS), as part of the USGS Water Availability and Use Science Program and with assistance from other Federal, State, and local …


Water Quality Of Groundwater Used For Public Supply In Principal Aquifers Of The Western United States, Celia C. Rosencrans, Marylynn Musgrove Jan 2020

Water Quality Of Groundwater Used For Public Supply In Principal Aquifers Of The Western United States, Celia C. Rosencrans, Marylynn Musgrove

United States Geological Survey: Publications

Groundwater provides nearly half of the Nation’s drinking water. As the Nation’s population grows, the importance of (and need for) high-quality drinking-water supplies increases. As part of a national-scale effort to assess groundwater quality in principal aquifers (PAs) that supply most of the groundwater used for public supply, the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Project staff sampled six principal aquifers in the western United States between 2013 and 2017: (1) the Basin and Range carbonate-rock aquifers, (2) Basin and Range basin-fill aquifers, (3) Rio Grande aquifer system, (4) High Plains aquifer, (5) Colorado Plateaus aquifers, and (6) Columbia …


Estimated Groundwater Withdrawals From Principal Aquifers In The United States, 2015, John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin Jan 2020

Estimated Groundwater Withdrawals From Principal Aquifers In The United States, 2015, John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin

United States Geological Survey: Publications

In 2015, about 84,600 million gallons per day (Mgal/d) of groundwater were withdrawn in the United States for various uses including public supply, self-supplied domestic, industrial, mining, thermoelectric power, aquaculture, livestock, and irrigation. Of this total, about 94 percent (79,200 Mgal/d) was withdrawn from principal aquifers, which are defined as regionally extensive aquifers or aquifer systems that have the potential to be used as sources of water of suitable quality and quantity to meet various needs. The remaining 6 percent (5,400 Mgal/d) was withdrawn from other, nonprincipal aquifers in the United States. Sixty-six principal aquifers belonging to 5 major lithologic …


The Quartz Of Arkansas: Geology, History And Legend, Thomas R. Paradise Jan 2020

The Quartz Of Arkansas: Geology, History And Legend, Thomas R. Paradise

Geosciences Faculty Publications and Presentations

Quartz Crystals has been treasured and utilized through history, and this chapter addresses its many uses, mineralogy, history, and legend over time...


Tracing Source Contributions To Assess Spatial Patterns Of Erosion In A Mixed Land Use Environment: Otter Creek Catchment, Fort Knox, Kentucky, Cara Peterman Jan 2020

Tracing Source Contributions To Assess Spatial Patterns Of Erosion In A Mixed Land Use Environment: Otter Creek Catchment, Fort Knox, Kentucky, Cara Peterman

Theses and Dissertations--Earth and Environmental Sciences

There is an inherent difficulty in predicting source contributions of fine-grained fluvial sediment in mixed land-use watersheds. Over a 56-week period, the spatial and temporal variability in sediment-source contributions and water quality was monitored at three sites along Otter Creek in Hardin and Meade counties, Kentucky (USA). The 203-km2 study area drains rural and agricultural lands and includes Fort Knox Army Post’s tracked-vehicle training areas. The main objectives for sediment source apportionment were to 1) identify and differentiate characteristics of civilian and military source soils to Otter Creek and 2) to apportion sediment at locations along Otter Creek to …


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 …


Modeling Cle Elum Reservoir Shoreline Erosion: Gis Analysis To Support Cultural And Environmental Resource Management, Yakima Basin, Washington, Michael H. Horner Jan 2020

Modeling Cle Elum Reservoir Shoreline Erosion: Gis Analysis To Support Cultural And Environmental Resource Management, Yakima Basin, Washington, Michael H. Horner

All Master's Theses

In the Yakima Basin, managers are expanding reservoirs including Cle Elum Lake to increase the availability of water. The objective of this study was to examine areas prone to further shoreline erosion to inform resource management. This research included the use of airphotos and fieldwork to identify erosional shorelines. Erosion was verified in the field using a video survey as well as indicators such as shoreline slope, sediment size, and nearshore width. Near-term erosional segments were identified by more rapidly receding bluffs while long-term erosional segments included both bedrock cliffs and bluffs. Although most of the shoreline is depositional, near-term …


Distribution Of Invasive Plant Species On Debris Cones At Mount Rainier National Park, Shaun Morrison Jan 2020

Distribution Of Invasive Plant Species On Debris Cones At Mount Rainier National Park, Shaun Morrison

All Master's Theses

Invasive plant populations within Mount Rainier National Park are a biological and ecological threat to the unique mountain landscape. A better understanding of their distribution and transport within the landscape is needed to improve invasive species monitoring for National Park Service management. This study investigates how invasive plant populations in Stevens Canyon are utilizing the debris cone disturbances and associated geomorphic processes to facilitate movement within the park. Vegetation transects were performed along Stevens Canyon Road (to observe the roadside community composition) and on the debris cone features (to observe species movement from the roadside). These vegetation observations are presented …


The Role Of Cumulate Plagioclase Entrainment In The Steens Basalt, Se Oregon: Insights From The Magma Chamber Simulator, Valerie Strasser Jan 2020

The Role Of Cumulate Plagioclase Entrainment In The Steens Basalt, Se Oregon: Insights From The Magma Chamber Simulator, Valerie Strasser

All Master's Theses

The Steens Basalt, located in SE Oregon, is the oldest and most mafic member of the Columbia River Basalt Group (CRBG). Because the Steens Basalt contains large (up to 6 cm) and abundant (up to 40%) plagioclase crystals, it is classified as a Giant Plagioclase basalt (GPB). Understanding the origin of these giant plagioclase yields insight into magmatic processes like recharge, crustal assimilation, cumulate entrainment, and fractional crystallization. Because large and abundant plagioclase are found in other flood basalt provinces worldwide, these results could also enhance understanding of magma evolution and storage conditions for GPB worldwide. The Steens basalt is …


Late Holocene Paleoflood Hydrology Of The Snake River In The Lower Hells Canyon, Idaho, Kent C. Allen Jan 2020

Late Holocene Paleoflood Hydrology Of The Snake River In The Lower Hells Canyon, Idaho, Kent C. Allen

All Master's Theses

The Snake River watershed spans a large geographic region from the Rocky Mountains to the inland Pacific Northwest, and a comprehensive paleoflood chronology on the mainstem of the river is key to identifying the frequency and magnitude of large prehistoric floods within the region. We examined and compared four sites of slackwater deposits along a 20-km reach of the Lower Hells Canyon on the Snake River, Idaho. The sites contain evidence of up to 34 paleofloods within the last 1700 years. Stratigraphic breaks, soils, and in-situ plant or archaeological materials demarcate distinct layers that represent discrete paleoflood events. Radiocarbon dates …


Sedimentological, Architectural, And Paleoenvironmental Analysis Of The Fluvial Upper Devonian Catskill Formation, North-Central Pennsylvania, Usa, Matylda Zaklicki Jan 2020

Sedimentological, Architectural, And Paleoenvironmental Analysis Of The Fluvial Upper Devonian Catskill Formation, North-Central Pennsylvania, Usa, Matylda Zaklicki

Honors Theses

During the Late Devonian time period, sediments eroded from the Acadian mountains were transported westward and deposited in fluvial environments, but the morphology of the rivers, avulsion style, and controls on basin infilling remain unclear. This study assesses the sedimentology, channel geometry, stratigraphic architecture, and avulsion style of the paleochannels and floodplains of the uppermost 80 meters of the Catskill Formation near Blossburg, Pennsylvania, using field-based lithofacies observations, high-resolution panoramic photographs, and terrestrial lidar scanning.

Upper Catskill Formation strata at Blossburg Middle consist of sandy channel and muddy floodplain deposits. Floodplain deposits were categorized into either proximal floodplain deposits or …


Fluvial Sedimentology And Architecture Of Two Latest Devonian Lower Huntley Mountain Formation Outcrops, North-Central Pennsylvania, Usa, Evan W. Filion Jan 2020

Fluvial Sedimentology And Architecture Of Two Latest Devonian Lower Huntley Mountain Formation Outcrops, North-Central Pennsylvania, Usa, Evan W. Filion

Honors Theses

Thick successions of river deposits accumulated in the north-central Pennsylvania region of the Appalachian foreland basin during Late Devonian time (~380-360 Ma). The properties and morphologies of these paleorivers are not well characterized. Latest Devonian tectonic, climatic, and eustatic controls on river dynamics and basin infilling also remain unclear. This study assesses the sedimentology, facies architecture, paleochannel depths, and grain size of a 133 m thick section of fluvial strata exposed across two outcrops, Blossburg South (older) and Blossburg West (younger), mapped as lower Huntley Mountain Formation near Blossburg, Pennsylvania. Field-based lithofacies observations, high-resolution panoramic photography, terrestrial lidar scanning, and …


Knickzones In Southwest Pennsylvania Streams Indicate Accelerated Pleistocene Landscape Evolution, Mark D. Swift Jan 2020

Knickzones In Southwest Pennsylvania Streams Indicate Accelerated Pleistocene Landscape Evolution, Mark D. Swift

Graduate Theses, Dissertations, and Problem Reports (ETD)

A set of 22 southwestern Pennsylvania streams flowing into the Monongahela and Ohio rivers with drainage areas ranging from 8 km2 to >512 km2 exhibit knickzones, when compared to Mackin’s (1948) idealized graded stream profile. Watersheds delineated from LiDAR-derived 1 m DEMs were processed using Esri’s ArcGIS for Desktop 10.6 to extract stream elevation data used to create stream profiles. These data were exported to MS Excel, where gradients were calculated and compared. This study used a new methodology in which gradient was calculated using incremental measurement distances (d) at every meter along the length of …


Mapping Surficial Geology In The New River Gorge National River And Bluestone National Scenic River, West Virginia, Using Lidar-Derived Digital Elevation Data, Marla K. Denicola Jan 2020

Mapping Surficial Geology In The New River Gorge National River And Bluestone National Scenic River, West Virginia, Using Lidar-Derived Digital Elevation Data, Marla K. Denicola

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this thesis was to determine if the surficial geology of Bluestone National Scenic River (BLUE) and New River Gorge National River (NERI), two areas of similar geology, can be mapped using visual interpretation methods applied to digital elevation models (DEMs) derived from light detection and ranging (LiDAR) data. Surficial geology in BLUE was field mapped using GPS, following definitions and characterizations for surficial geology units established with the guidance of Dr. J. Steven Kite. A 2m x 2m LiDAR-derived DEM was used for BLUE and most of NERI using US Army Corps of Engineers (USCOE) LiDAR data, …


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 …


2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin Jan 2020

2019 Nebraska Water Leaders Academy Final Report, M.E. Burbach, R.M. Joeckel, G.S. Matkin

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal Jan 2020

Correlating The Plant Height Of Wheat With Above-Ground Biomass And Crop Yield Using Drone Imagery And Crop Surface Model, A Case Study From Nepal, U. S. Panday, Nawaraj Shrestha, S. Maharjan, A. K. Pratihast, Shahnawaz, K. L. Shrestha, J. Aryal

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart Jan 2020

Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart

Murray State Theses and Dissertations

Floodplains can store large amounts of soil organic carbon (SOC) despite covering a small fraction of the global land area. Since these valley-bottom landforms build through the action of flooding, the century to millennial-scale record of overbank deposition could be important in understanding controls on deep (>30 cm) SOC storage. Yet, the influence of flood history and landform development on carbon content is surprisingly not well known. I use a combined geological and pedological approach to characterize the sedimentation, soil development, and SOC of fluvial terraces along an impounded reach of the humid-subtropical Tennessee River valley, U.S.A. The standardized …


Assessing The Accuracy Of A Uav Snow Depth Survey: Utqiagvik (Barrow), Alaska Calm Grid, Ian Nichols Jan 2020

Assessing The Accuracy Of A Uav Snow Depth Survey: Utqiagvik (Barrow), Alaska Calm Grid, Ian Nichols

Dissertations, Master's Theses and Master's Reports

Active layer depth and snow depth are annually collected across the Circumpolar Active Layer Monitoring (CALM) Network to observe the response of the active layer and near-surface permafrost to climate change over decadal-time scales. Snow depth is typically measured using a graduated steel probe at each grid node but, in this paper, we explore the viability of using Unmanned Aerial Vehicle (UAV) (drone) technology to collect snow depth measurements at the 1 km2 Utqiagvik (Barrow), Alaska CALM grid. This is achieved by comparing estimated UAV snow depths to measured snow depths collected using a MagnaProbe (MP) at each of …


Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano Jan 2020

Reconstruction Of The 2018 Anak Krakatau Collapse Using Planetscope Imaging And Numerical Modeling, Davide Saviano

Dissertations, Master's Theses and Master's Reports

The study was focused on the Anak Krakatau sector collapse that occurred on 22 December 2018 in the Sunda Strait (Indonesia). The goal of the study was to monitor and analyze changes of the volcanic edifice and to try to understand causes that may have predisposed and triggered the sector collapse.

The use of different remote sensing techniques allowed the acquisition of thermal data, SO2 emission data, structural data and the identification and analysis of the eruptive events that occurred on Anak Krakatau in the period from 1° January 2016 to 28 February 2019. The acquisition of 1221 thermal …


Development And Application Of A Catchment Scale Sediment Routing Model, Jordan T. Gilbert Jan 2020

Development And Application Of A Catchment Scale Sediment Routing Model, Jordan T. Gilbert

Graduate Student Theses, Dissertations, & Professional Papers

Sediment regimes, i.e., the processes that recruit, transport and store sediment, create the physical habitats that underpin river-floodplain ecosystems. Natural and human-induced disturbances that alter sediment regimes can have cascading effects on river and floodplain morphology, ecosystems, and a river’s ability to provide ecosystem services, yet prediction of the response of sediment dynamics to disturbance is challenging. We developed the Sediment Routing and Floodplain Exchange (SeRFE) model, which is a network-based, spatially explicit framework for modeling sediment recruitment to and subsequent transport through drainage networks. SeRFE additionally tracks the spatially and temporally variable balance between sediment supply and transport capacity. …


Sediment Dynamics In The Magdalena River Basin, Colombia: Implications For Understanding Tropical River Processes And Hydropower Development, Luke H. Fisher Jan 2020

Sediment Dynamics In The Magdalena River Basin, Colombia: Implications For Understanding Tropical River Processes And Hydropower Development, Luke H. Fisher

Graduate Student Theses, Dissertations, & Professional Papers

The Magdalena River Basin of Colombia has a globally relevant sediment flux, however, studies of the sediment regime in the basin are limited in scope. This knowledge gap limits application of understanding of sediment dynamics to hydropower decision making. To close this gap, we implemented a sediment budget framework to quantify the impacts of hydropower development in a 118,000 km2 portion of the Magdalena River basin. We informed this framework with analysis of background erosion rates derived from 10Be cosmogenic nuclides and modern sediment fluxes derived from monitoring and optical remote sensing. We standardized these data to spatially …


Evolution And Stratigraphic Architecture Of Tidal Point Bars With And Without Fluvial Input: Influence Of Variable Flow Regimes On Sediment And Facies Distribution, And Lateral Accretion, Pricilla Souza Dec 2019

Evolution And Stratigraphic Architecture Of Tidal Point Bars With And Without Fluvial Input: Influence Of Variable Flow Regimes On Sediment And Facies Distribution, And Lateral Accretion, Pricilla Souza

LSU New Orleans Theses and Dissertations

Tide-influenced point bars represent a significant proportion of shallow-marine deposits, commonly developed along meandering channels in most backbarrier and estuarine systems. However, sedimentological studies to characterize this type of deposit are still emerging. They often present very heterogeneous internal architectures which development is controlled by the complex flow patterns operating in tidal environments. The study of the sedimentological and morphological characteristics of these features provides better understanding of the hydrodynamic processes that shape coastal systems and control their evolution as well as it contributes to better reservoir potential prediction and production strategy optimization, as tidal point bars may represent hydrocarbon …


Resolving Time-Space Histories Of Late Cenozoic Bedrock Incision Along The Upper Colorado River, Usa, Andres Aslan, Karl E. Karlstrom, Eric Kirby, Matthew T. Heizler, Darryl E. Granger, James K. Feathers, Paul R. Hanson, Shannon A. Mahan Dec 2019

Resolving Time-Space Histories Of Late Cenozoic Bedrock Incision Along The Upper Colorado River, Usa, Andres Aslan, Karl E. Karlstrom, Eric Kirby, Matthew T. Heizler, Darryl E. Granger, James K. Feathers, Paul R. Hanson, Shannon A. Mahan

School of Natural Resources: Faculty Publications

The upper Colorado River basin drains the western slope of the Rocky Mountains province of North America and hosts a rich record of fluvial terraces and volcanic deposits that provide an archive of bedrock river incision since the Late Miocene. Here we present new geochronology from fluvial deposits and associated volcanic units using multiple methods (luminescence, cosmogenic-burial, 40Ar/39Ar basalt and detrital sanidine, and U/Pb detrital zircon) to reconstruct a detailed record of bedrock incision in the upper Colorado River over timescales ranging from Miocene to Late Pleistocene. Late Miocene (ca. 11–8 Ma) basalt flows perched 800–1700 m above the Colorado …


Quantifying The Effectiveness Of Cedar Revetment In Mitigating Bank Erosion In Riceford Creek, Minnesota, Talia A. Klein Dec 2019

Quantifying The Effectiveness Of Cedar Revetment In Mitigating Bank Erosion In Riceford Creek, Minnesota, Talia A. Klein

Graduate Theses/Dissertations

Southeastern Minnesota has incised streams that are susceptible to bank erosion. Previously, efforts have been made to identify sections of Riceford Creek that have high erosion susceptibility using the Bank Erosion Hazard Index (BEHI). Locally harvested cedars were then used as a revetment strategy to mitigate erosion of the stream banks prioritized by the BEHI analysis. This study aims to 1) determine if cedar revetment effectively mitigates bank erosion in Riceford Creek and 2) determine if the BEHI method is an effective way of quantifying erosion hazard in Riceford Creek. This study focuses on two sections in Riceford Creek where …


Geomorphology And Geochronology Of Sand Ramps Adjoining The Coral Pink Sand Dunes, Kane County, Utah, Kerri E. Spuller Dec 2019

Geomorphology And Geochronology Of Sand Ramps Adjoining The Coral Pink Sand Dunes, Kane County, Utah, Kerri E. Spuller

Boise State University Theses and Dissertations

Projected climate change is expected to have widespread impacts on arid regions of the world. Inland, continental dune fields are sensitive to changes in climate and the surrounding environment and are an important source for understanding interactions between Earth’s surface, atmosphere, and biosphere in drylands. Reconstructing past periods of aeolian activity from dune fields can provide insights into how landscapes have responded to previous changes in climate. However, the nature of aeolian systems to recycle older deposits leads to a preservation bias towards only the youngest deposits. Targeting geomorphic settings that are conducive to preserving older records is critical to …


Step-Pool Channel Morphology, Forcing Effects, And Geomorphic Classification In The Ozark Highlands, Se Missouri, Triston Ralland Rice Dec 2019

Step-Pool Channel Morphology, Forcing Effects, And Geomorphic Classification In The Ozark Highlands, Se Missouri, Triston Ralland Rice

Graduate Theses/Dissertations

Understanding headwater streams and their morphology is inherently difficult in contrast to larger streams in downstream valleys. Geomorphic forcing can occur over short distances (<10 >m) and influence channel geometry due to geologic factors such as colluvial inputs and resistant bedrock or biologic factors such as fluvial wood inputs and tree growth in the channel. How and where these geomorphic variables effect step-pool channel characteristics is poorly understood in the Ozark Highlands. Step-pool channel form is typically controlled by gradient, substrate characteristics, and sediment supply. This study reports on a geomorphic assessment of step-pool characteristics and classifies channel form using …


The Shelf To Basin Transition And Tectonostratigraphy Of The Atoka Formation (Lower Pennsylvanian) In The Arkoma Basin, Northwest Arkansas, Travis Gibson White Dec 2019

The Shelf To Basin Transition And Tectonostratigraphy Of The Atoka Formation (Lower Pennsylvanian) In The Arkoma Basin, Northwest Arkansas, Travis Gibson White

Graduate Theses and Dissertations

The east-to-west oriented Arkoma Basin is a peripheral foreland basin or depositional trough that developed during the Carboniferous Period. This formation covers an aerial extent of approximately 33,800 square miles and spans from west-central Arkansas into southeastern Oklahoma (McGilvery, Manger, and Zachry, 2016; Perry, 1995). The Atoka Formation, deposited during the early Pennsylvanian, is the largest Paleozoic formation by aerial extent in the state of Arkansas and is located within and comprises the bulk of Arkoma Basin sediments (McFarland, 2004; Nance, 2018). This formation has been informally divided into three divisions, the lower, middle, and upper, based on their stratigraphic …