Geomorphology Commons^™

Quantifying The Rates Of Coastal Change Along Smith Island, Maryland, Sarah Lacy, Ravi Sankar

Longwood Senior Thesis Proposal

As increased climate variability continues to alter the environment, coastal landscapes are becoming increasingly vulnerable to geomorphic change. Coastal erosion, driven by rising sea levels, land subsidence, more intense storm events and human-induced activities poses a serious threat to the sustainability and resilience of island environments like Smith Island, a small marsh island located in the Chesapeake Bay. This study investigates the impacts of recent shoreline change along selected alongshore segments of the island’s coast. Using a combination of aerial imagery, field surveying techniques, and novel geospatial analyses, the project aims to identify areas at highest risk of erosion and …

Estimated Amounts Of Terrestrial Carbon Mobilized And Sequestered By The 1980 Mount St. Helens Eruption, Washington State, Usa, Lizzet G. Reyes

Dissertations and Theses

Volcanic eruptions significantly influence the geologic carbon cycle by emitting CO₂ and mobilizing terrestrial carbon pools. The 1980 Mount St. Helens (MSH) eruption offers a unique case study, triggering a massive landslide that displaced 2.7 km³ of sediment, buried 600 km² of forest, and disrupted regional carbon dynamics. Pre-eruption terrestrial carbon stocks, including aboveground biomass (AGB), dead biomass (D), and soil organic carbon (S), averaged 209.5 tC/ha. Post-eruption, total carbon density fell to 118.7 tC/ha, driven mainly by a 51% reduction in AGB, modest declines in D, and redistribution of S. Over 36 years, ecosystem recovery increased …

Decadal To Millennial-Scale Morphodynamic Evolution Of Microtidal Marshes, Samuel Mason Zapp

LSU Doctoral Dissertations

Tidal marshes are susceptible to rapidly converting to open water due to their low elevations within the tidal frame. A continuous supply of externally supplied mineral sediment and in situ organic material production is necessary to offset elevation losses from relative sea level rise and erosion. Complex feedbacks between hydrodynamics, the erosion, transport, and deposition of sediment, and physical modification of the landscape by the establishment of intertidal vegetation govern the spatial and temporal patterns of elevation response. This dissertation focuses on modeling how these dynamics drive marsh landscape evolution in the past, present, and into the future under changing …

Equilibration Of Alluvial River Channel Geometry To Unsteady Boundary Conditions, Christian Erikson

Dartmouth College Ph.D Dissertations

The morphology of an alluvial river is the culmination of dynamic processes interacting across scales. When the boundary conditions of a fluvial system are modified, feedback effects among these processes reshape the channel by altering the flow of water and sediment. Environmental stressors, therefore, have the potential to propagate signals of change from watershed to grain scale features in a river channel. I trace the influence of modern climate change across these scales by first quantifying changes in the generation of surface runoff and sediment supply at watershed scales. I then identify how the subsequent changes in hydrological and sedimentological …

Diffendal Receives Wisherd Award For University Service, Ronica Stromberg

Robert F. Diffendal, Jr., Publications

Even though he’s retired, Robert Diffendal seems to be working everywhere.

The professor emeritus in the School of Natural Resources retains offices in three buildings. He reports to work at the Center for Great Plains Studies five days a week for about four hours a day. His list of volunteer activities around the state goes on and on, affecting, by his count, 21,088 people since 2003, when he stepped away from full-time faculty work. He capped 2024 at Nebraska Innovation Campus, where he received the Wisherd Award for Outstanding Service to the University of Nebraska–Lincoln.

Chosen by the Emeriti and …

Landslide At River's Edge: Alum Bluff, Apalachicola River, Florida, Joann Mossa, Yin-Hsuen Chen

Center for Geospatial Science, Education & Analytics Faculty Publications

When rivers impinge on the steep bluffs of valley walls, dynamic changes stem from a combination of fluvial and mass wasting processes. This study identifies the geomorphic changes, drivers, and timing of a landslide adjacent to the Apalachicola River at Alum Bluff, the tallest natural geological exposure in Florida at similar to 40 m, comprising horizontal sediments of mixed lithology. We used hydrographic surveys from 1960 and 2010, two sets of LiDAR from 2007 and 2018, historical aerial, drone, and ground photography, and satellite imagery to interpret changes at this bluff and river bottom. Evidence of slope failure includes a …

Investigating Woody Vegetation Recruitment Post Riparian Enhancement Extraction Along The Baduwa't, Rize Martins De Oliveira, Wiley Hughes, Owen Lenox

Forestry, Fire, & Rangeland Management Senior Capstones

The Baduwa’t River in Humboldt County, California, faces a legacy of channelization, poor land management, and severe flooding that has left high, dry floodplain terraces disconnected from the river and dominated by invasive vegetation. In response to sediment deficits during drought years, Riparian Enhancement Extractions (REEs) were introduced as an alternative gravel mining method that simultaneously presented opportunities for habitat restoration. This study evaluates five REEs along the Baduwa’t to identify the construction features and site conditions that promote successful riparian vegetation establishment. Findings show that REEs can create seasonal wetlands conducive to native riparian habitat reestablishment, when excavation is …

Stratigraphy And Osl Chronology Of Lunette Deposits Indicates That Nebraska’S Rainwater Basins Formed By Aeolian Deflation Between 39 And 25 Ka, P.R. Hanson, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Early Holocene Interaction Of Aeolian, Alluvial, And Lacustrine Processes In A Dune-Dammed Valley In The Central Nebraska Sand Hills, Gpsia Mahoney, R. D. Mandel, P.R. Hanson, Sherilyn Fritz

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Restoring Rattlesnake Creek: Using Citizen Science To Assess The Ecological And Morphological Impacts Of Dam Removal In Western Montana, Bethany Blakey

Undergraduate Theses, Professional Papers, and Capstone Artifacts

As dam removals increase in frequency across the U.S., most research has focused on the impact of larger dam removals, despite the removal of small dams being much more common. Given the hundreds of small dams in Montana, this research uses citizen science data collected over eight years spanning before and after a 2020 small dam removal in Rattlesnake Creek, Montana, to investigate impact on stream ecology and morphology. We analyzed pebble count grain size distributions and aquatic macroinvertebrate biotic indices from 2017 to 2024 to assess changes in sediment transport and macroinvertebrate population as well as evaluate the efficacy …

Applications Of Remote Sensing Data To Understanding Geohazards In Wyoming And Kentucky, Meredith Swallom

Theses and Dissertations--Earth and Environmental Sciences

Shallow geohazards such as earthquakes, landslides, and floods profoundly impact communities globally. Constraining susceptibility to these hazards is critical for effective hazard mitigation and building more resilient communities. This dissertation includes multiple studies that leverage remotely sensed datasets to address hazard susceptibility, including: (1) characterizing a potential northern extension of the Teton fault system, (2) deriving a vegetation-based metric to improve landslide susceptibility maps in eastern Kentucky, with potential global implications, and (3) combining numerical modeling, landscape models, and field constraints to understand how anthropogenic factors affect flood severity in southern Appalachian catchments.

In the first study, analysis of new …

Numerical Modeling Study Of Coastal Impacts From Extreme Storms And Sea Level Rise In Southern New England, Deborah Crowley

Open Access Dissertations

Coastal areas in southern New England are vulnerable to a range of impacts from extreme storms and sea level rise. The most frequent extreme storms are extratropical storms, commonly referred to as nor’easters, named for the direction of the strongest winds, though these storms also have strong winds from other directions.

Storm winds generate large waves and push water up along the coast in the form of storm surge. The combined impacts of increased water levels and waves include flooding and morphological change. Sea level rise (SLR) will exacerbate these processes, amplifying the associated impacts, which may pose increasing threats …

Using Simulated Cascadia Fakequakes To Interpret Paleotsunami Patterns, Anthony M. Joyce

All Master's Theses

This study uses GeoClaw to simulate 8 instantaneous rupture test earthquakes and 48 stochastic earthquakes (Fakequakes) along the Cascadia Subduction Zone to better understand tsunami generation and propagation. The primary goal is to evaluate how variations in Fakequake rupture patterns affect tsunami heights at coastal sites in the Pacific Northwest. The study focused on comparing inner and outer coast wave heights and impacts to understand how the Olympic Peninsula provides a barrier of protection to inner coast sites from southern-generated tsunamis, and implications for tsunami hazard at Naval Air Station Whidbey Island (NASWI).

Test earthquakes show increased amounts of slip …

Geochronology And Geomorphology Of The Brule Spillway Of Glacial Lake Duluth, Madeline Josephine Laaksonen

All Graduate Theses, Dissertations, and Other Capstone Projects

During the Late Pleistocene and Early Holocene, a series of dyssynchronous advances and retreats resulted in the evolution of the Upper St. Croix River Valley. Proglacial lakes forming at the margins of the retreating ice within the Lake Superior Basin and subsequent multiple drainage events through the Brule Spillway have also drastically shaped the landscape. As a result, the Brule Spillway and broader St. Croix River valley presents an important case study to spillover processes occurring in proglacial landscapes and the reorganization of regional drainage networks and creation of a new hydrogeomorphic regime. While prior literature on the Spillway exists, …

Conservation And Survey Division 2024 Annual Report, R.M. Joeckel, Michele Waszgis

Conservation and Survey Division: Faculty and Staff Publications

The Conservation and Survey Division of the University of Nebraska - Lincoln is the agency designated by statute to investigate and interpret the geologically related natural resources of the State, to make available to the public the results of these investigations, and to assist in the development and conservation of these resources. It consists of program areas in geology, water, soils and remote sensing-geographic information systems.

The Use Of Lidar In The Study Of Terrain Ruggedness Of Tsunami Inudation Areas At Grewingk Lake And Taan Fiord, Alaska Usa, Shannon P. Mckinnion

All Master's Theses

ABSTRACT

THE USE OF LIDAR IN THE STUDY OF TERRAIN RUGGEDNESS OF TSUNAMI INUDATION AREAS AT GREWINGK LAKE AND TAAN FIORD, ALASKA USA

by

Shannon Patricia McKinnion

In order to test the hypothesis that lidar technologies can detect possible changes in terrain ruggedness due tsunami inundation within a designated area, digital elevation models (DEM) were generated from lidar data for two sites with known tsunami inundation— Grewingk Lake, Alaska and Taan Fiord, Alaska. Cobbles and boulders in these locations were examined using existing terrain ruggedness tools in ArcHydro— Terrain Ruggedness Index (TRI) and Vector Ruggedness Measurement (VRM). The average values …

Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell

Master's Theses

The behavior of soils during surface fault rupture is a serious concern in the planning and design of infrastructure that may be located within or near a fault zone. Challenges associated with developing mitigation measures for surface fault rupture include the uncertainty of fault rupture and the variability of fault behavior. Current analytical procedures define surface fault rupture according to the type of fault movement (strike slip, normal or reverse), the amount of displacement on the fault, and the mechanics of the material overlying the fault. The purpose of this thesis is to reconfirm analytical solutions and gain a better …

The Role Of Floodplain Complexity In Wood Turtle Habitat Use, Laura S. Deming

Antioch University Dissertations & Theses

Wood turtles occupy cold, low-gradient riverine habitat throughout the northeastern United State and southeastern Canada. Stream alterations, such as dams, channel straightening, and floodplain development have diminished the natural hydrologic and sedimentation regimes that result in complex channel and floodplain geomorphology. Studies throughout the species’ range have quantified many aspects of their habitat, but none have quantified components of geomorphology of wood turtle sites. The goal of this study was to explore the role of stream channel and floodplain geomorphology in wood turtle habitat use, with specific objectives to (1) quantify components of stream channel and floodplain geomorphic complexity, (2) …

Fluvial Geomorphic Resilience In Alluvial Mountain Rivers To Large Floods, Riley T. Henson

Graduate Student Theses, Dissertations, & Professional Papers

As hydroclimatic extremes intensify, large floods increasingly reshape river systems and threaten infrastructure. Fluvial geomorphic resilience, defined as a river’s resistance to, and recovery from, flood disturbance, offers a useful framework for understanding river response and guiding management. We assessed resilience at two scales: (1) a detailed geomorphic and hydraulic analysis of the June 2022 flood on East Rosebud Creek, Montana, which was part of broader flooding in the Greater Yellowstone Ecosystem, and (2) a broad-scale comparison of 12 flood-impacted alluvial mountain rivers across North America and Europe. We quantified resistance using active channel width ratios (W_R) and …

Geomorphic Evolution Of St. Augustine Inlet, St. Johns County, Florida, Kristen Becker

Theses and Dissertations

Tidal inlets interrupt longshore sediment transport, influencing adjacent beach morphology and allowing the exchange of water and sediment between the open oceans and protected back barrier bay. Inlets evolve through a combination of natural processes and are highly dynamic zones where sediment exchanges cause shifting shoreline positions nearby and create new morphological features. Barrier islands/beaches that are close in proximity to inlets evolve and are an important natural feature that dissipates wave energy and protects inland areas. Both natural and anthropogenic processes that affect barrier islands will be investigated during this study, including storm activity, waves, wind, water level, and …