Geomorphology Commons^™

The Fragmentation Of Helcar: A Paratethyan Model For Rhûn, Núrnen And The Dead Marshes, Federico Manzoni

Journal of Tolkien Research

This work proposes a conjectural paleogeographic model linking the Sea of Rhûn, Núrnen and the Dead Marshes to the former Sea of Helcar. Beginning from Christopher Tolkien's suggestion that Rhûn may represent Helcar ``vastly shrunken,'' the study combines textual evidence, the Ambarkanta, Fonstad's cartographic reconstructions, and terrestrial analogues drawn from the evolution of the Paratethys, the Messinian Salinity Crisis and other endorheic basins. Helcar is interpreted not merely as an isolated body of deep water but as the centre of a broader hydrological province subsequently partitioned by relief change, sedimentary infilling, basin isolation and drainage reorganization. Within this model, Rhûn …

Mono Gold: An Informal Account Of The Geology, Production, And History Of Mono County Gold And Silver Mining Districts, D. D. Trent

Eastern Sierra History Journal

Mono Gold explores the mining production, technology, and history of the Eastern Sierra, with a special focus on Mono County. Author Dee Trent, a geologist, spent decades visiting, researching, and photographing each of the mining operations discussed in this book-length monograph.

Crustal Structure Of The Vøring Plateau And Vøring Spur From Joint Refraction And Reflection Travel-Time Tomography, Anika Nawar Mayeesha

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Crustal architecture of the Vøring Plateau and Vøring Spur in the mid-Norwegian continental margin remains debated because the geophysical data in the area do not uniquely constrain whether the crust is continental, oceanic, or transitional. This study reanalyzes wide-angle ocean-bottom seismometer data from Profile 11-03 across the Vøring passive continental margin using joint travel-time tomography of crustal refractions and Moho reflections. A total of 6,760 first-arrival picks and 542 PmP picks from sixteen instruments were inverted for P-wave velocity and reflector depth. Three starting models were inverted independently to test sensitivity to the initial crustal configuration. The first two used …

Super-Resolution Remote Sensing Datasets For Application To Caral–Supe Archeological Sites Employing Sar And Dems, Jungrack Kim, Ramesh P. Singh

Mathematics, Physics, and Computer Science Faculty Articles and Research

Publicly accessible spaceborne remote sensing datasets often lack the spatial resolution required to reliably distinguish archeological features from their surrounding geomorphological contexts. In this study, we assess the potential of super-resolution (SR) products derived from multiple public-domain remote sensing datasets for a systematic archeological survey in the Caral–Supe region. We focus on Synthetic Aperture Radar (SAR) and topographic datasets—including Sentinel-1, Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR), and Digital Elevation Models (DEMs)—because of their capacity to detect subtle surface expressions and shallow subsurface structures obscured by vegetation or sediment cover. Using state-of-the-art deep learning algorithms, …

Below The Rows, Beyond The Roots: An Art Exhibition Depicting Agriculture Across The Globe, Maggie Enoch

Honors Theses and Capstones

In Below the Rows, Beyond the Roots, artist Maggie Enoch creates multimedia works inspired by her exposure to diverse agricultural systems and perspectives while studying geography and sustainable agriculture/food systems around the world. By integrating complex histories with the contemporary realities of farming, Maggie paints vivid pictures of the power of food in this five-piece exhibition.

Spatial Patterns And Morphometric Evolution Of Sinkholes In Response To Watershed Hydrogeomorphology: Examples From A Karst Landscape In The Missouri Ozarks, Usa, Marcell Tóth

Graduate Theses/Dissertations

Sinkholes are characteristic enclosed depressions with internal drainage connecting the surface and subsurface karst hydrologic system. Their morphological evolution involves gradual subsidence of the ground surface and hazardous collapses. Therefore, understanding sinkhole morphometry and linked spatial distribution is critical for managing geohazards in karst watersheds. Sinkhole occurrence shows spatial variability based on watershed geomorphological attributes, surficial hydrological patterns, hydrogeological and geological settings. The aim of this research is to investigate morphometric properties and distribution of sinkholes in the carbonate karst-dominated lands of Mark Twain National Forest in Missouri, USA. The specific objectives were to (1) identify sinkhole clusters based on …

Data-Driven Methodologies For Mapping Cultural Heritage: The Case Of The National Coal Heritage Area, West Virginia, Usa, Hossain Mohammad Nahyan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this dissertation was to develop a comprehensive, data-driven spatial framework for characterizing the complex cultural landscape of the National Coal Heritage Area (NCHA) in West Virginia. By transitioning away from traditional, heuristic spatial mapping, this research integrates advanced spatial statistics, machine learning, and GIS-based methodologies to objectively quantify the physical, visual, and cultural dimensions of the post-mining environment. The research is structured around three interconnected empirical studies, each addressing a specific scale of the Landscape Character Assessment (LCA) framework to support heritage conservation and sustainable spatial planning. The first paper focused on landform classification, developing an automated …

Analysis Of The Impact And Adaptation Of Tidal Floods From Coastal Landscape Area Communities In Poasia District, Kendari City, Indonesia, La Ode Hadini, La Aba, Noor Husna Khairisa, Nikita Jasmine Almira

Jurnal Pendidikan Geografi: Kajian, Teori, dan Praktek dalam Bidang Pendidikan dan Ilmu Geografi

Poasia District is located in the coastal area of the southern part of Kendari City, which is highly susceptible to tidal flooding. However, the extent of the community's exposure to these events and their subsequent adaptation measures remain to be fully delineated. This study examines the impacts of tidal flooding and the adaptation patterns of the Poasia Coastal Community to the tidal flood disaster. This research employed a descriptive qualitative method, which was carried out through document review, interviews involving 34 respondents, and field observations. The results of this study indicate that tidal flooding exerts a negative impact on the …

Flash Flood Modelling In The Brantas Hulu Sub-Watershed, Batu City, Indonesia, Listyo Yudha Irawan, Vischawafiq Azizah, Siti Nur Farihah, Luisa Fernanda Medina, Puspita Indra Wardhani, Nanda Regita Cahyaning Putri, Mellinia Regina Heni Prastiwi, Mohammad Rendra Magandhi Arizal

Jurnal Pendidikan Geografi: Kajian, Teori, dan Praktek dalam Bidang Pendidikan dan Ilmu Geografi

Flash floods are especially hazardous hydrological phenomena, noted for their abrupt occurrence and capacity to inflict severe damage on infrastructure, farmlands, and residential zones, often leading to substantial socio-economic upheaval and fatalities. A flash flood struck the Upper Brantas watershed on November 4, 2021, at 14:00, precipitated by intense rainfall over a short duration, leading to significant hydrological impacts. The event manifested at six critical points within Batu City, with Sambong Hamlet and Beru Hamlet experiencing severe inundation. The flash floods disrupted residential areas and severely affected agricultural lands through debris flows. Preliminary assessments indicated that approximately 35 houses were …

River Confinement And Braiding Loss In Canterbury Region, Aotearoa New Zealand, Victoria Barlow, Peter Ashmore

Geography & Environment Publications

In relation to the wider concern that rivers in Aotearoa New Zealand have been narrowed by river control and land-use encroachment, and that iconic braided patterns are being lost, nine braided rivers from the Canterbury region were studied to compare river width, pattern type and braiding intensity between the mid-1900s and the present based on mapping from aerial images. Channel narrowing occurred along >90% (~490km) of the length of the rivers studied, 375km of which were historically braided. In total, the rivers narrowed by an average of 43% (48% for braided reaches). Coinciding with narrowing, braided reaches lost 1.3 channels, …

Performance Of Acoustic Telemetry And Space Use Of Pallid Sturgeon In The Lower Platte River, Nebraska, Christopher F. Pullano

School of Natural Resources: Dissertations, Theses, and Student Research

Pallid Sturgeon (Scaphirhynchus albus) are centenarian, potamodromous, rheophiles that historically occupied the Missouri River and Mississippi River basins. Listed on the U.S. Endangered Species Act in 1990, population declines are attributed to habitat fragmentation and degradation, as well as overharvest, and hybridization. A knowledge gap exists regarding the extent to which tributaries facilitate key life stages for Pallid Sturgeon. This study evaluated the capacity of acoustic telemetry to monitor the movements of Pallid Sturgeon in a shallow, braided tributary to the Missouri River. The specific objectives were to (1) evaluate the environmental variables influencing the performance of acoustic …

Effects Of Longitudinal Training Walls On Two-Dimensional Flow Structure, Sediment Transport, And Bed Aggredation Using Numerical Methods And Sediment Core Analyses In Grand River, Michigan, Sumaiya Tul Siddique

LSU Doctoral Dissertations

Longitudinal training walls (LTWs) are structures oriented parallelly with the main flow and separate the channel into two sub-channels. One channel acts as the main navigational channel and the other is considered a secondary side channel. The long-term effects of the LTWs on morphodynamics and deposition remain poorly understood. This study investigated the long-term effects of the LTWs on flow, sediment transport and long-term deposition of the Grand River using numerical approaches and sediment core analysis. The effects of LTWs on 2D flow dynamics and sediment transport were investigated by using numerical approaches. The long-term deposition under the influence of …

Generating Channel Morphology Data Through Arcgis Pro, Ethan Manigbas

Symposium of Student Scholars

River cross-sections are often extracted using field surveys at measured intervals. This field-oriented approach allows for a tangible relationship between the data and its collector but at the expense of finance, time, labor, and potentially the environment. With the advancement of geospatial tools, such data can be found online, extracted, and even analyzed with contemporary Geographic Information Systems (GIS) in a completely virtual setting, transcending the need for fieldwork in select project topics. We tested this approach with the help of ArcGIS Pro software on the Vishnu Springs headwater stream located in the Western Illinois region of the Upper Mississippi …

Bay Water Level Influences On Inundation And Morphological Changes Of A Semi-Connected Barrier Island During A Hurricane, Sydney D. Goodman

Graduate Theses and Dissertations (2019 - present)

This research aims to identify flooding and erosion changes along a semi-connected barrier island system due to varying bay water levels during storm conditions. The numerical model XBeach is used to simulate Hurricane Michael conditions and the resulting inundation and morphological change near Tyndall Air Force Base (Tyndall AFB). The installation is located 12 miles southeast of Panama City Beach along the panhandle of Florida and is vulnerable to flooding due to its proximity to the Gulf of Mexico (GoM), Saint Andrew Sound and Saint Andrew Bay. A land bridge connects the barrier island to the mainland of Tyndall AFB …

Post-Glacial Landscape Evolution Of The Lower St. Croix River Valley: The Enigma Of Glacial Lake Grantsburg, The Osceola Bench, And The St. Croix Dells, Hunter Delikowski

All Graduate Theses, Dissertations, and Other Capstone Projects

The St. Croix River valley (SCRV) is the product of dyssynchronous glacial advance and retreat of several glacial lobes during regional deglaciation of the Late Pleistocene-Early Holocene transition. Additionally, the SCRV has been dramatically shaped by multiple proglacial lake drainage episodes. Therefore, the SCRV is an important case study to understanding the impacts of proglacial lake spillover processes. However, the magnitude, frequency, timing, duration, and geomorphic impacts of these floods remain enigmatic. We focus on a specific reach of the SCRV, which we name the Lower SCRV for the purpose of this study. The lower SCRV contains several anomalous landforms …

Modeling The Peak Ground Acceleration And Assessing The Economic Loss And Casualty Due To Potential Earthquakes Of Various Magnitudes In The New Madrid Seismic Zone, Mahmud Afroz

Graduate Theses and Dissertations

The New Madrid Seismic Zone (NMSZ) is one of the active tectonic zones capable of producing big earthquakes in the southcentral USA. The objective of this study was to assess the economic losses and casualties that might be caused by various magnitudes of seismic events in the NMSZ. The manifestation is the estimation for each magnitude which is using the Peak Ground Acceleration (PGA) that might occur during an earthquake. It is calculated using an attenuation function that correlates the intensity of local ground movement, the earthquake magnitude, and the distance from its epicenter. The assessment of casualties was conducted …

Urban & Deltaic Subsidence In Bangladesh From Sentinel-1 Insar Data Analysis, Gavin Middleton

Masters Theses & Specialist Projects

Bangladesh's Bengal Delta faces multiple challenges, such as rising sea levels, coastal flooding, and high population density, leading to land subsidence, saltwater intrusion, and biodiversity loss. The region's groundwater security, essential for the country's survival, is at risk due to climate change and saltwater intrusion. Groundwater security is dependent on the Bengal Water Machine (BWM), which is at risk due to saltwater intrusion and monsoon rainfall distribution from climate change. Groundwater exhaustion leads to natural hazards such as subsidence, landslides, and flooding. A large portion of the population is at risk from groundwater insecurity, which requires mitigating worldwide greenhouse gas …

Modeling The Impacts Of Sea Level Rise In Coastal Virginia At Multiple Scales, George Murray Mcleod Iv

OES Theses and Dissertations

Relative sea level is increasing along the Mid-Atlantic coast of the United States and the rate of relative sea level rise (ΔRSL) for Coastal Virginia is approximately double the rate of global sea level rise (ΔSLRG)(1). The potential impacts posed to communities by ΔRSL are best understood by examining the spatial relationship between the upper limits of ocean-connected waters and the geographic positioning of critical natural and societal assets. This research examines this problem at three spatial scales to quantify the impacts of ΔRSL and storm flooding events on (i) structural and transportation infrastructure for the tide-influenced coastal zone of …

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 …

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 …

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 …

Geology, Soils And Climate Of Western Australia's Wine Regions, Peter J. Tille, Angela Stuart-Street, Peter S. Gardiner

Bulletins 4000 -

This bulletin details what is special and unique about the geology, soil and climate of the south-west of Western Australia (WA), an area that encompasses the state’s 9 wine regions.

We have arranged the information into 2 parts:

• In Part 1, we broadly describe the special geological, soil and climate features of the south-west of WA to provide context for the wine regions.

• In Part 2, we describe the geology, soil and climate of the regions and subregions of the Geographical Indications (GI) scheme (administered by Wine Australia) for WA.

Through this work we have found that the wine regions …

A Tectonic Geomorphic Study Of Neotectonics And Seismic Hazard Of The Fold And Thrust Belt Complex Of Bengal Basin, Eastern Himalayan Range, Niroj Shrestha

Masters Theses & Specialist Projects

Tectonic activity continues to shape and create challenges for human populations in tectonically active areas. The Bengal Basin is one of the most important sedimentary basins of the Eastern Himalayan Range, aiding in one of the densely populated regions of the world. The basin is part of the tectonically active Himalayan Orogen that is undergoing oblique subduction between the Eurasian Plate and the Indian Plate. As a result of this subduction-related convergence, the eastern part of the Basin, particularly the Chittagong-Tripura Fold Belt (CTFB) and western part of the Indo-Burman Range (IBR) has structurally deformed into a series of mostly …

Landslide Detection In The Himalayas Using Machine Learning Algorithms And U-Net, Sansar Raj Meena, Lucas Pedrosa Soares, Carlos H. Grohmann, Cees Van Westen, Kushanav Bhuyan, Ramesh P. Singh, Mario Floris, Filippo Catani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Event-based landslide inventories are essential sources to broaden our understanding of the causal relationship between triggering events and the occurring landslides. Moreover, detailed inventories are crucial for the succeeding phases of landslide risk studies like susceptibility and hazard assessment. The openly available inventories differ in the quality and completeness levels. Event-based landslide inventories are created based on manual interpretation, and there can be significant differences in the mapping preferences among interpreters. To address this issue, we used two different datasets to analyze the potential of U-Net and machine learning approaches for automated landslide detection in the Himalayas. Dataset-1 is composed …

What Braiding Reveals About River Morphology, Bedload And Channel Change, Peter Ashmore

Geography & Environment Presentations

Braided rivers can appear to be outliers in the range of river morphological types with unique dynamics and processes. Analysis shows that they have systematic structure, dynamics and response to external change that have properties relevant to the continuum of channel morphology. Rapid morphological change in real time creates a system in which bedload transport is strongly morphologically driven, which leads to thinking about bedload thresholds in terms of morphological change rather than grain scale dynamics. Occurrence and complexity of braiding respond to total stream power, and channel pattern is therefore partly an effect of river size. Braided rivers have …

What Braiding Reveals About River Morphology, Bedload And Channel Change, Peter Ashmore

Geography & Environment Publications

Braided rivers can appear to be outliers in the range of river morphological types with unique dynamics and processes. Analysis shows that they have systematic structure, dynamics and response to external change that have properties relevant to the continuum of channel morphology. Rapid morphological change in real time creates a system in which bedload transport is strongly morphologically driven, which leads to thinking about bedload thresholds in terms of morphological change rather than grain scale dynamics. Occurrence and complexity of braiding respond to total stream power, and channel pattern is therefore partly an effect of river size. Braided rivers have …

Braiding, Peter Ashmore

Geography & Environment Publications

Braided rivers have multiple, unstable channels and ephemeral bars formed by intense bed-load transport, and active channel processes. They occur in a range of environments associated with high-energy, coarse bedded rivers with limited riparian vegetation, and relatively high sediment supply. The occurrence in some regions is strongly modified by human activity. Empirical and rational analysis of regime conditions and in-channel process mechanisms can predict occurrence of braiding, considering by the problem of gradual transitions between channel pattern types, transient flood influence and vegetation effects. Braided rivers have hydraulic geometry relations similar to those of single-thread channels as well as systematic …

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 …

The Role Of Elevation As A Control On Salt Marsh-Upland Ecotones Along The Mississippi Gulf Coast, Carlton P. Anderson

Dissertations

Salt marshes are critical ecological gems that serve as habitat for many specialized species of flora and fauna, while providing a natural buffer to human populations from tropical cyclone impacts. However, rises growth of coastal populations has led to greater strain on the natural services these ecosystems provide. To better understand and project the future of coastal evolution, the physical, mechanical, and biological feedbacks between the natural and human coupled systems need to be more defined and thoroughly understood. Human encroachment towards naturally retreating shorelines will lead to coastal communities being more susceptible to nuisance tidal flooding and minor tropical …