Geomorphology Commons^™

Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping

All Theses

The critical zone (CZ) is the life sustaining outer layer of the earth that spans from the top of unweathered bedrock to the tops of the trees. This dynamic zone is always evolving because a variety of chemical, physical, and biological processes transform bedrock into regolith, creating a spatially heterogeneous CZ architecture. This study aims to investigate the relationships between regolith thickness, seismic velocities, and chemical profiles as a function of slope position and it is hypothesized bedrock composition, fracture density, and foliation are the key factors controlling the physical heterogeneity in the top 1-2 meters of the CZ. To …

Quantifying Mud Settling Velocity As A Function Of Turbulence And Salinity In A Deltaic Estuary, Michael W. Mcdonell

LSU Master's Theses

Mud settling velocity is controlled by flocculation, which in turn strongly depends on turbulence and on the chemistry and biology of the water-sediment mixture. As a result, mud settling velocity can be poorly constrained in coastal areas and vary in space and time by orders of magnitude. Here we quantified mud settling velocity in Barataria Basin, a deltaic estuary in Louisiana (USA), using three independent methods: eddy covariance (one station for 200 days), floc cameras (4 stations at one time), and Rouse profile inversion (14 stations, replicated 10-30 times each). Eddy covariance indicates that settling velocity increases with turbulence, at …

Grid Independence Studies Of Eddy-Resolving Models At The Scale Of A River Reach Along A Transect In Marble Canyon Of The Colorado River, Arizona, Rosa Elena España Urresty

Open Access Theses & Dissertations

This study presented a novel approach for evaluating the impact of changes in spatial resolution on field-scale models to identify turbulent flow patterns in hydraulic features in canyon-bound rivers. The methodological framework incorporated seven different computational domain resolutions to analyze the sensitivity of field-scale models to spatial resolution changes by employing techniques such as turbulent kinetic energy spectrum, spatiotemporal analysis of eddy structures, divergent Kullback-Leibler (KL) divergence, Nash-Sutcliffe (NS) model efficiency coefficient, wavelet power spectrum, and GCI calculation. Statistical and physical-based skill metrics are employed to quantifying information loss to evaluate a set of domain resolutions. Grid independence studies have …

A Multiscale Linkage Between Riverscape And Fish Community Coevolution, Loren W. Stearman

Dissertations

Sediment dynamics are foundational to stream and watershed morphology. Yet aquatic ecologists have relied on an oversimplified model of sediment dynamics characterizing sediments as agents of stream bed burial, and which fails to describe many types of aquatic habitat evolution. In this dissertation I employ both fluvial geomorphic and ecological frameworks to gain a deeper understanding of how sediment dynamics shape stream morphology and fish community evolution at multiple scales. Using a paired historic and contemporary approach, I analyzed geomorphic evolution and fish community change in the Bayou Pierre, Mississippi, from the 1980s to recent. Patterns of erosion due to …

Benthic Habitat Mapping Of Mountain Top Bank Within The Northern Gulf Of Mexico Through Integrated Geophysical And Visual Data Analysis, Bethany Pertain

Master's Theses

Mesophotic coral ecosystems (MCEs) are among the seafloor ecosystems that have been poorly studied throughout the world’s oceans, but they are a vital and diverse ecosystem that should be prioritized for future mapping and ecological studies. Priority should be given to them because they possess natural, social, and economic values, and face a variety of threats, all of which, if not better understood will result in the loss of this unique ecosystem. Insights into these ecosystems, among other deep-sea environments, are lacking due to difficulty accessing them, inherent lag between data collection by an autonomous system and observation by a …

Flood Hydrology In Tropical Coastal Catchments: Linking Watershed Dynamics To Mangrove Sedimentation, Shannon L. Jones

Electronic Theses and Dissertations

Coastal flooding is expected to be more frequent and severe from amplified flooding from sea level rise (SLR) and upstream anthropogenic activity, particularly in tropical regions. Improved hydrologic modeling and characterization are needed to better understand, predict, and manage flooding where these amplifications are expected. Yet tropical catchments are often ungauged or have limited hydrogeomorphic data. Thus, locally calibrated models that incorporate local knowledge and alternative data can be used to provide greater information. This doctoral dissertation quantifies relationships between land use, precipitation, discharge, and downstream sediment accretion in a representative ungauged catchment using a locally calibrated rainfallrunoff model validated …

Nebraska Statewide Groundwater-Level Monitoring Report 2022, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Jeffrey Westrop

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Sediment Transport And Geomorphological Evolution In The Northern Gulf Of Mexico, Kelli Moran

LSU Doctoral Dissertations

This dissertation explores the mechanisms driving sediment transport and deposition on the continental shelf and within the bays of the northern Gulf of Mexico via a suite of geophysical methods and sediment cores on a variety of timescales. This dissertation is comprised of three main chapters, each focusing on a different location, environment, and process but tied together using geophysical survey, a thematic focus on geomorphic change and sediment transport within the deltaic cycle and deltaic plain environments, and the implications this change poses for both past and future sediment transport and environmental change in response to sea level change. …

Hydrodynamics And Sediment Transport In The Tidally Influenced James River, Ollie Gilchrest, Rip Hale

The Graduate School Posters

The tidally influenced James River is an important economic, ecologic, and cultural resource for VA residents. Tidal rivers have been historically understudied, however they are critical transition zones, the dynamics of which have implications for freshwater supply and sediment trapping. Globally, estimates suggest that >30% of fluvial sediment is trapped in the tidal zone, the location and dynamics of which are actively changing due to sea level rise and saltwater encroachment. In addition, analysis of historical water levels on the James River has shown a decrease in the tidal range since 1940. The present study combines >1-year’s worth of hydrographic …

Power And Politics: The Case Of Urbanization And River Channel Change, Peter Ashmore

Geography & Environment Presentations

Gradual urbanization of a watershed in Toronto, Canada, over 60+ years resulted in major channel changes. The temporal and spatial extent of channel widening are predictable from new analysis tracking changes in total stream power along the river system as urban land cover extended across the watershed, and also produced very high energy large flood events responsible for major channel change. The analysis is a geomorphically-satisfying, quasi-experimental test of theory of river channel change. But it misses important elements of the full trajectory of change that are not physically predictable. Treating urbanization as a neutral physical variable of changing watershed …

Evaluating River Morphology Change With A Geomorphic Form Variation Approach, Corey Dawson, Peter Ashmore, Robert Corry

Geography & Environment Publications

Geomorphic river design strives for natural resilience by encouraging geomorphic form complexity and morphological processes linked to greater habitat diversity. Increasing availability of high-resolution topographic data and spatial feature mapping methods provide advantages for morphological analysis and river restoration planning. We propose and evaluate an approach to quantifying topographic variability of geomorphic form and pixel-level surface roughness resulting from channel planform geometry differences using spatially continuous variety computation applied to component metrics including flow direction, aspect and planform curvature. We define this as the geomorphic form variation (GFV) approach and found it scalable, repeatable and a multi-stage analytical metric for …

Historical And Forecasted Kentucky Specific Slope Stability Analyses Using Remotely Retrieved Hydrologic And Geomorphologic Data, Daniel M. Francis

Theses and Dissertations--Civil Engineering

Hazard analyses of rainfall-induced landslides have typically been observed to experience a lack of inclusion of measurements of soil moisture within a given soil layer at a site of interest. Soil moisture is a hydromechanical variable capable of both strength gains and reductions within soil systems. However, in situ monitoring of soil moisture at every site of interest is an unfeasible goal. Therefore, spatiotemporal estimates of soil moisture that are representative of in-situ conditions are required for use in subsequent landslide hazard analyses.

This study brings together various techniques for the acquisition, modeling, and forecasting of spatiotemporal retrievals of soil …

Soil Moisture And Geomorphologic Data For Use In Dynamic And Forecastable Landslide Hazard Analyses In Eastern Kentucky, Daniel M. Francis, L. Sebastian Bryson

Civil Engineering Research Data

These data are the geomorphologic and land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates over known landslides in Eastern Kentucky. Additionally Long Short-Term Memory Recurrent Neural Network and logistic regression machine learning codes, as well as an Application programming interface code are included. Finally, in-situ data from Eastern Kentucky is included.

Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem

Environmental Science & Management Senior Capstones

River systems across California have been impacted by appurtenant structures such as dams and diversions. These structures have had an adverse impact on Benthic invertebrate (BMI) communities by regulating river systems and changing the natural hydraulic pulses that follow seasonal precipitation. Benthic invertebrates are a critical food resource for salmonids and serve as an indicator of ecosystem health. Our study was interested in seeing the effects of scouring events on BMI in the Trinity River of Trinity County, C.A. Following a large precipitation event that occurred in the region in December 2022, an influx of water entered the river through …

Spatiotemporal Retrievals Of Soil Moisture And Geomorphologic Data For Landslide Sites In Eastern Kentucky, Lindsey Sebastian Bryson, Daniel M. Francis

Civil Engineering Research Data

These data are the soil texture, land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates, artificial neural network machine learning code, and in-situ soil moisture measurements.

Delineating A Stream Network At Gale Crater, Mars, On Arcgis Pro: A Geographic Information Systems Approach, Elpidio Guzman De La Cruz

West Chester University Master’s Theses

The northwestern region of the Gale crater experienced flooding in the past. Delineation of stream networks for the northwestern region of Gale Crater, Mars employing geographic information systems (GIS) techniques is applied. The stream network produced by the algorithm in the study traverses the clay unit in Gediz Vallis, and visual HiRISE imagery analysis correlates with a topologic cross section of an inverted river channel of 750 meters wide and 90 meters deep. HiRISE imagery analysis further confirms a sulfate and clay stratigraphic unit in a stream 125 meters wide and 25 meters deep. Lastly, data smoothing procedures in the …

A Source-To-Sink Analysis Of The Pantanal Basin (Brazil): Implications For Weathering, Erosion, And Landscape Evolution In The World's Largest Wetland, Edward L. Lo

Theses and Dissertations--Earth and Environmental Sciences

Large back-bulge retro-arc basins have limited information about the sediment composition, yet they comprise important parts of the stratigraphic rock record. The exorheic Pantanal Basin is the world's largest continental wetland that regulates many valuable ecosystem services (water storage, nutrient cycling, agriculture, ranching, tourism, and transportation). This dissertation is composed of three studies that utilize a suite of tools to examine the most fundamental basin-wide source-to-sink sediment processes and controls that affect the characteristics and distribution of modern sediments.

The first paper consists of a metadata analysis of 76 shallow tropical floodplain lakes in the literature with bathymetric data and …

Berriasian–Valanginian Geochronology And Carbon-Isotope Stratigraphy Of The Yellow Cat Member, Cedar Mountain Formation, Eastern Utah, Usa, Robert M. Joeckel, Celina A. Suarez, Noah M. Mclean, Andreas Möller, Gregory A. Ludvigson, Marina B. Suarez, James I. Kirkland, Joseph Andrew, Spencer Kiessling, Garrett A. Hatzell

Conservation and Survey Division: Faculty and Staff Publications

The Early Cretaceous Yellow Cat Member of the terrestrial Cedar Mountain Formation in Utah, USA. has been interpreted as a “time-rich” unit because of its dinosaur fossils, prominent paleosols, and the results of preliminary chemostratigraphic and geochronologic studies. Herein, we refine prior interpretations with: (1) a new composite C-isotope chemostratigraphic profile from the well-known Utahraptor Ridge dinosaur site, which exhibits δ¹³C features tentatively interpreted as the Valanginian double-peak carbon isotope excursion (the so-called “Weissert Event”) and some unnamed Berriasian features; and (2) a new cryptotephra zircon eruption age of 135.10 ± 0.30/0.31/0.34 Ma (2σ) derived from the CA-ID-TIMS …

Closing The Modern Seismic Gap Along The Teton Fault Via Seismic Mapping Of Mass Transport Deposits In Jackson Lake, Wy, Callia Jacqueline Cortese

Theses and Dissertations--Earth and Environmental Sciences

Terrestrial paleoseismological records along the Teton fault have historically indicated two-to-three major post-Pinedale (~14 ka) earthquake events, leaving an unresolved 6-9 m offset along the modern scarp. Recent studies of Jenny Lake have augmented this record, but the triggering mechanism is still equivocal until new paleo-earthquake records are developed. The earthquake record of the Teton fault is complicated by quiescence from ~5 ka to present, demonstrating the need for additional paleoseismic investigations. Compressed, high-intensity radar pulse (CHIRP) reflection data from Jackson Lake indicates multiple potentially seismically-induced mass transport deposits (MTDs). At least six MTD Groups representing chronostratigraphic intervals were interpreted …

Applications Of Digital Terrain Modeling To Address Problems In Geomorphology And Engineering Geology, Sarah Johnson

Theses and Dissertations--Earth and Environmental Sciences

This dissertation uses digital terrain modeling and computational methods to yield insight into three topics: 1) evaluating the influence of glacial topography on fluvial sediment transport in the Teton Range, WY, 2) integrating regional airborne lidar, UAV lidar, and structure from motion photogrammetry to characterize decadal-scale movement of slow-moving landslides in northern Kentucky, and 3) applying machine learning methods to surficial geologic mapping.

The role of topography as a boundary condition that controls the efficiency of fluvial erosion in the Teton Range, Wyoming, was investigated by using existing lidar data to delineate surficial geologic units, geometrically reconstruct the depth to …