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Full-Text Articles in Geography

Climatic Controls On The Kinematics Of The Hooskanaden Landslide, Curry County, Oregon, Kara Kingen Apr 2021

Climatic Controls On The Kinematics Of The Hooskanaden Landslide, Curry County, Oregon, Kara Kingen

Dissertations and Theses

Slow-moving earthflows represent major sources of sediment transport and erosion and are problematic for the management of critical infrastructure. The Hooskanaden Landslide -- a slow-moving earthflow on the southwest coast of Oregon -- crosses US Highway 101 and has been a site of continued interest to the Oregon Department of Transportation (ODOT) due to the weak lithology, erosive environment, and recurrent surge behavior (every ~15 years). Past surges, including the most recent (2019), have occurred during the winter, suggesting that velocity changes are predominantly controlled by climatic inputs. To examine the response of the Hooskanaden Landslide to seasonal and other …


Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice Mar 2021

Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice

Dissertations and Theses

Recent advances in remote sensing data and technology have allowed for computational models to be designed that successfully extract landforms from the landscape. The goal of this work is to create one such semi-automated model to extract deep-seated landslides located in complex geomorphic terrain. This is accomplished using geographic object-based image analysis (GEOBIA) techniques, considered by leaders in the field of image analysis to have an advantage over traditional automated classification methods. GEOBIA methods can mimic human visual interpretation by including more characteristic features used to assess the relationship between image data and the ground surface such as color reflectance …


A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles Jan 2021

A Karst Feature Prediction Model For Prince Of Wales Island, Alaska Based On High Resolution Lidar Imagery, Alexander Lyles

Master's Theses

Investigation into surface karst formation is significant to hazard prediction, hydrogeologic drainage, and land management. Southeast Alaska contains over 600,000 acres of mapped carbonate bedrock, and some of the fastest recorded karst dissolution in the world. The objectives of this study are to develop and compare multiple semi-automated models to map and delineate karst features from bare-earth LiDAR imagery using ArcGIS Desktop 10.7, and to apply a preliminary geostatistical analysis of sinkhole morphometric parameters to highlight potential spatial patterns of karst evolution on Prince of Wales Island, Alaska. A semi-automated approach of mapping karst features provides a dataset that minimizes …


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 …


Short Communication: Challenges And Applications Of Structure-From-Motion Photogrammetry In A Physical Model Of A Braided River, Peter Ashmore, Pauline Leduc, Sarah Peirce Jan 2019

Short Communication: Challenges And Applications Of Structure-From-Motion Photogrammetry In A Physical Model Of A Braided River, Peter Ashmore, Pauline Leduc, Sarah Peirce

Geography & Environment Publications

For extending the applications of structure-from-motion (SfM) photogrammetry in river flumes, we present the main challenges and methods used to collect a large dataset ( > 1000 digital elevation models, DEMs) of high-quality topographic data using close-range SfM photogrammetry. Automatic target detection, batch processing, and considerations for image quality were fundamental to the successful implementation of the SfM technique on such a large dataset, which was used primarily for capturing details of gravel-bed braided river morphodynamics and sedimentology. While the applications of close-range SfM photogrammetry are numerous, we include sample results from DEM differencing, which was used to quantify morphology change …


Mass Wasting Investigation And Assessment In The Midwest: Case Study Of The Minnesota River Valley, New Ulm To St. Peter, Minnesota, Usa, Melissa Kohout Jan 2019

Mass Wasting Investigation And Assessment In The Midwest: Case Study Of The Minnesota River Valley, New Ulm To St. Peter, Minnesota, Usa, Melissa Kohout

All Graduate Theses, Dissertations, and Other Capstone Projects

Many mass- wasting studies have been conducted worldwide, however, investigations have focused in mountainous or coastal regions. This has proven problematic in areas lacking those features yet are experiencing mass wasting. Several anthropogenic risks, economic loss, and environmental issues are associated with mass wasting such as destruction of property, loss of life, and sediment pollution. The midwestern USA, is generally considered a low relief region, therefore limited data exist for mass wasting occurrence. Within the last decade, however, several events have occurred across Minnesota with little understanding of the ongoing hillslope processes leading to failure. The Minnesota River valley is …


Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast, Kelly Marie Sanks Dec 2018

Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast, Kelly Marie Sanks

Graduate Theses and Dissertations

Recent reports estimate that the marshes of the Mississippi Delta receive just 30% of the sediment necessary to sustain current land area1. An extensive monitoring campaign by the USGS and LCPRA provides direct measurements of sediment accumulation, subsidence rates, and deposit characteristics along the coast over the past 10 years2, allowing us to directly evaluate this sediment balance. By interpolating bulk density, organic fraction, and vertical accretion rates from 273 sites, a direct measurement of organic and inorganic sediment accumulation can be made. Results show that a total of 82 MT/year of sediment is delivered to the coast. Using a …


Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren Oct 2018

Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren

Geography & Environment Publications

Planimetric change was measured on daily hydrographs over two meltwater seasons using time-lapse images of the proglacial, gravel, braided, Sunwapta River, Canada. Significant planimetric change occurred on 10-15 days per year. Area of planimetric change correlated with peak and total daily meltwater hydrograph discharge. A clear threshold discharge can be identified below which no planform activity occurs, an intermediate range over which change occurs conditionally, and a peak flow range at which significant change always occurs. Field conditions were reproduced in a physical model in a laboratory flume. Photogrammetric DEMs of bed morphology and measurements of bedload output were made …


Expanding The "Active Layer", Peter Ashmore, Sarah Peirce, Pauline Leduc Feb 2018

Expanding The "Active Layer", Peter Ashmore, Sarah Peirce, Pauline Leduc

Geography & Environment Publications

Church and Haschenburger (2017) make helpful distinctions around the issue of defining the active layer, with which we agree. We propose expanding discussion and definition of the ”active layer” in fluvial bedload transport to include the concept of the “morphological active layer”. This is particularly applicable to laterally unstable rivers (such as braided rivers) in which progressive morphological change over short time periods is the process by which much of the bedload transport occurs. The morphological active layer is also distinguished by variable lateral and longitudinal extent continuity over a range of flows and transport intensity. We suggest that the …


Assessing Historical Planform Channel Change In An Altered Watershed With Quantification Of Error And Uncertainty Present In A Gis/Aerial Photography-Based Analysis; Case Study: Minnesota River, Minnesota, Usa., Devon Libby Jan 2018

Assessing Historical Planform Channel Change In An Altered Watershed With Quantification Of Error And Uncertainty Present In A Gis/Aerial Photography-Based Analysis; Case Study: Minnesota River, Minnesota, Usa., Devon Libby

All Graduate Theses, Dissertations, and Other Capstone Projects

Little is known about the historic planform channel change of the Minnesota River of south-central Minnesota, USA. This is despite research that demonstrates anthropogenic activities have altered the Minnesota River Basin's hydrology, land use, and climate. In addition, the threat of invasive carp infestation requires an understanding of Minnesota River planform change to assess mitigation strategies. This thesis focuses on the lower Minnesota River (LMR) by measuring planform channel change (lateral channel migration, width, and sinuosity) from 1937 to 2013. Analysis is conducted by utilizing remote/GIS analysis of historic aerial photographs. A secondary focus addresses and quantifies the inherent/introduced error/uncertainly …


Evaluating Lithology As An Erosional Control On A Fluviokarst System In Northeastern Kentucky, Andrew K. Francis Dec 2016

Evaluating Lithology As An Erosional Control On A Fluviokarst System In Northeastern Kentucky, Andrew K. Francis

Theses and Dissertations

Longitudinal stream profiles can be used to evaluate landscape evolution. Lithology as a control on a stream profile is especially of interests because fluviokarst systems are characterized by the contact of carbonate and non-carbonate rocks at the surface. Due to the difference in weathering processes between carbonates and non-carbonate rocks, it is likely that there is a difference in their rates of erosion. Cave Branch and its tributary Horn Hollow, are fluviokarst systems located in northeastern Kentucky. This area is primarily comprised of sandstone and limestone. The objectives of this study were to determine if variation in lithology was creating …


Dating Late Quaternary Alluvial Fills In The Platte River Valley Using Optically Stimulated Luminescence Dating, Jacob C. Bruihler May 2016

Dating Late Quaternary Alluvial Fills In The Platte River Valley Using Optically Stimulated Luminescence Dating, Jacob C. Bruihler

Department of Geography: Dissertations, Theses, and Student Research

Alluvial fills underlying the Platte River Valley in Nebraska record the geologic history of the Platte River in the late Quaternary. This study investigated the alluvium underlying the valley near the cities of North Platte and Kearney, Nebraska. Data obtained from sediment cores drilled in the alluvial deposits was used to investigate the changes in Platte River dynamics on a glacial – interglacial timescale. Optically Stimulated Luminescence (OSL) dating was used to determine burial ages of recovered sediments and to quantify the thicknesses of the late Pleistocene and Holocene alluvial fills at each study area. Our geochronology depicts considerable differences …


High-Resolution Digital 3d Models Of Algar Do Penico Chamber: Limitations, Challenges, And Potential, Ivo Silvestre M.Sc., José I. Rodrigues Phd, Mauro Figueiredo Phd, Cristina Veiga-Pires Phd Nov 2014

High-Resolution Digital 3d Models Of Algar Do Penico Chamber: Limitations, Challenges, And Potential, Ivo Silvestre M.Sc., José I. Rodrigues Phd, Mauro Figueiredo Phd, Cristina Veiga-Pires Phd

International Journal of Speleology

The study of karst and its geomorphological structures is important for understanding the relationships between hydrology and climate over geological time. In that context, we conducted a terrestrial laser-scan survey to map geomorphological structures in the karst cave of Algar do Penico in southern Portugal. The point cloud data set obtained was used to generate 3D meshes with different levels of detail, allowing the limitations of mapping capabilities to be explored.

In addition to cave mapping, the study focuses on 3D-mesh analysis, including the development of two algorithms for determination of stalactite extremities and contour lines, and on the interactive …


Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan May 2012

Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan

Graduate Theses and Dissertations

Slope failure continues to pose risks to society because knowledge of environmental factors and their interactions are unclear and possibly misunderstood. This misunderstanding leads to generalizations about slope failure susceptibility mapping, despite knowing that slope failures are likely the result of an extensively complex set of interactions among a number of environmental, edaphic, and geomorphic characteristics. Therefore a series of experiments were conducted to investigate the effects of slope, soil texture, vegetation cover, bedrock permeability, and compaction,. A wooden flume with a slope face 1 m wide by 1.5 m long with a 10 cm toe was constructed to contain …


Physiographic Factors Defining The Snake River Valley Ava; Beyond "Vin De Idaho", David Wilkins, Virginia Gillerman, Krista Shellie, Ron Bitner, Gregory Jones Apr 2011

Physiographic Factors Defining The Snake River Valley Ava; Beyond "Vin De Idaho", David Wilkins, Virginia Gillerman, Krista Shellie, Ron Bitner, Gregory Jones

David E. Wilkins

Beginning in 1971 with the first plantings of wine grapes, the wine and wine grape industry in southwest Idaho have grown to become significant contributors to the state economy with an annual impact of $75 million (Bierle et al., 2008). With around 1600 acres under cultivation in 50 vineyards producing at least 24 varietals (as of 2007), wine grapes are the state's second largest fruit crop in acreage, with the majority of the crop (USDA, 2008) being produced in the western Snake River Plain of southwestern Idaho and eastern Oregon. In April, 2007, a 21,400 sq. km area in this …


An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, P A. Waddell, A K. Gardner, P Hennig Jan 2010

An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, P A. Waddell, A K. Gardner, P Hennig

Technical Bulletins

The inventory and condition survey of the Western Australian part of the Nullarbor region, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 2005 and 2007, describes and maps the natural resources of the region. This survey report provides a baseline record of the existence and condition of the area's natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The Nullarbor region has …


Analysis Of Channel Networks And The Potential For Sediment Transport In The Vicinity Of The North Polar Seas Of Titan, Richard Cartwright Jul 2009

Analysis Of Channel Networks And The Potential For Sediment Transport In The Vicinity Of The North Polar Seas Of Titan, Richard Cartwright

Geosciences Theses

This study analyzes the available radar evidence in order to describe the morphology of channel networks around the north polar seas of Titan. Critical flow depths necessary to entrain water-ice grains, and denudation rates for a north polar channel network are discussed. The results indicate that channel networks on Titan have similar morphologies to channel networks cut by water on Earth. We also find that water-ice sediment should be readily entrained in the headwaters and downstream sections of the analyzed Titanian basin, given sufficient flow depths of liquid hydrocarbons. Also, the importance of slope and the elevated topography of the …


An Inventory Of Rangelands In Part Of The Broome Shire, Western Australia, W E. Cotching Jan 2005

An Inventory Of Rangelands In Part Of The Broome Shire, Western Australia, W E. Cotching

Technical Bulletins

The inventory of rangelands in part of the Broome Shire in Western Australia was undertaken by DAFWA between 1989 and 1990. It describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The survey of part of the Broome Shire …


Geospatial Analysis Of Gravel Bar Deposition And Channel Migration Within The Ozark National Scenic Riverways, Missouri (1955-2003), Derek J. Martin Jan 2005

Geospatial Analysis Of Gravel Bar Deposition And Channel Migration Within The Ozark National Scenic Riverways, Missouri (1955-2003), Derek J. Martin

MSU Graduate Theses

Historical land clearing is believed to be responsible for present-day channel instability in main stem reaches in the Ozark National Scenic Riverways (ONSR) in south-central Missouri. The nature of instability is related to the delivery of excess amounts of gravel sediment to stream channels and higher rates of lateral bank erosion. These conditions are of concern to resource managers because of the potential damaging effects on recreational facilities and aquatic habitat. The purpose of this study is to develop a geographic information systems (GIS)/remote sensing (RS) based methodology to monitor spatial patterns of gravel deposition and lateral channel migration within …


An Inventory And Condition Survey Of The Pilbara Region, Western Australia, A M E Van Vreeswyk, K A. Leighton, A L. Payne, P Hennig Jan 2004

An Inventory And Condition Survey Of The Pilbara Region, Western Australia, A M E Van Vreeswyk, K A. Leighton, A L. Payne, P Hennig

Technical Bulletins

The inventory and condition survey of the Pilbara region, undertaken by the Department of Agriculture, Western Australia between 1995 and 1999, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about 181 723 km². Seven …


1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz Dec 2001

1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz

Geography Faculty Scholarship

The geomorphic consequences of debris flows and their asso- ciated storms have been documented in many parts of the United States. Few, if any, have been studied and documented in central Washington. The importance of recurrent debris flows in sculpting Washington landscapes has not been generally recognized compared to other processes. Arid and semi-arid regions are particularly vulnerable to debris flows triggered by sudden intense thunderstorms. Most such areas are sparsely populated and eyewitnesses are uncommon. By contrast, semi-arid central Washington is relatively well popu- lated, and there are likely to be people who have observed the storms. Such witnesses …