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Remote Sensing And Luminescence Dating Of Archaeological Sites In Buriram Province, Northeastern Thailand, Sutthikan Khamsiri 2022 Faculty of Sciences

Remote Sensing And Luminescence Dating Of Archaeological Sites In Buriram Province, Northeastern Thailand, Sutthikan Khamsiri

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aims to apply remote sensing and luminescence dating to study archaeological sites in Buriram Province, Northeastern Thailand. There are three main objectives including 1) to model the ancient path from the mountain passes along the Dângrêk mountain to ancient community on Angkor Highland or Northeast Thailand, 2) to directly date slag from the ancient iron smelting site at Ban Sai To 7, and 3) determine the terminal age of Ban Sai To 7 site using technical ceramics. Firstly, the results of the GIS-based least cost path (LCP) route, using topographic factors, show that Ta Muen, Sai Ta Ku, …


Impact Of Type And Shape On The Transport Of Microplastics In Column Experiments, Cheyanne Amanda Schenkel 2022 Northern Illinois University

Impact Of Type And Shape On The Transport Of Microplastics In Column Experiments, Cheyanne Amanda Schenkel

Graduate Research Theses & Dissertations

The pervasive nature of plastic and the longevity of plastic compounds leaves a legacy of plastics and microplastics (MPs) that contaminate our environment, including drinking water sources. Although MPs have been well documented in every environmental setting, a paucity of research has focused on the transport and fate of MPs in groundwater systems. Previous field and lab studies have shown that MPs can migrate through aquifer material and that their retention and retardation are influenced by changing environmental factors. This study used coarse, well-sorted sand in controlled column experiments to investigate the influence of polymer type (PA, PE, PP, PEST) …


Analysis Of Deformation Near Salt Structures: Geomechanical Modeling And Case Studies From The Paradox Basin, Utah, And Flinders Ranges, South Australia, Mackenzie Anne Wegmann 2022 Northern Illinois University

Analysis Of Deformation Near Salt Structures: Geomechanical Modeling And Case Studies From The Paradox Basin, Utah, And Flinders Ranges, South Australia, Mackenzie Anne Wegmann

Graduate Research Theses & Dissertations

This thesis utilizes detailed field studies and numerical simulations to characterize near- salt deformation patterns. Establishing possible deformation patterns and their evolution helps to constrain assumptions within geomechanical models and aids in the evaluation of prospects that rely on trapping at or near the salt-sediment interface. For the field studies, I use a combination of mesoscopic structural analysis, drone photogrammetry, and 3D modeling to analyze variation in deformation patterns at a scale of meters to hundreds of meters along transects moving horizontally away from the salt-sediment interface adjacent to the western end of the Onion Creek salt diapir (OCSD) in …


Microfabric Analysis Of Mid-Pliocene Amundsen Sea Interglacial Sediments Demonstrates A Link Between Iceberg Melt And Diatom Productivity (Iodp Exp. 379), Heather Leanne Furlong 2022 Northern Illinois University

Microfabric Analysis Of Mid-Pliocene Amundsen Sea Interglacial Sediments Demonstrates A Link Between Iceberg Melt And Diatom Productivity (Iodp Exp. 379), Heather Leanne Furlong

Graduate Research Theses & Dissertations

Anthropogenically induced climate change in the polar regions has rapidly become an emergent global issue, especially for low-lying coastal communities, which are most affected by sea-level rise. The future of the West Antarctic Ice Sheet (WAIS) is of significant concern due to its history of instability and retreat, especially in light of the observed ongoing changes. Establishing rates of retreat is critical to forecasting future behavior of the WAIS, and previous studies have been unable to establish rates of ice sheet collapse in part because Antarctic continental shelf records are impacted by erosional hiatuses. In 2019, International Ocean Discovery Program …


Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett 2022 Central Washington University

Assessing The Effects Of Instream Large Wood On Floodplain Aquifer Recharge And Storage At Indian Creek, Kittitas County, Washington, Usa, Stephen Bartlett

All Master's Theses

Numerous stream restoration projects in the Yakima River Basin in Washington have placed large wood (LW) into tributary channels. One intended effect is to divert water onto floodplains to increase groundwater (GW) recharge and seasonal storage in shallow alluvial aquifers during spring high flows with the intention of releasing GW into streams during the drier summer months. Large wood was emplaced in the Indian Creek tributary of the Teanaway River in Kittitas County, Washington beginning in 2016. Potential changes in the groundwater recharge in the adjacent floodplain before and after the LW installation were investigated through stratigraphic analysis, stream-flow modeling, …


Detecting Impacts Of Historic And Undocumented Landslide Tsunamis At High Latitude Sites Using Ndvi, Trent Adams 2022 Central Washington University

Detecting Impacts Of Historic And Undocumented Landslide Tsunamis At High Latitude Sites Using Ndvi, Trent Adams

All Master's Theses

In the last century most of the largest landslide tsunamis on record have occurred in remote regions of the world, which has led to a limited understanding of their impacts on landscapes. The goal of this work is to present a methodology to identify impacts of landslide tsunamis with a technique that does not require field work in extremely remote locations. Although landslide tsunamis have occurred that were not directly witnessed by anyone, evidence of landslide tsunamis can still be observed via satellite. Using multispectral satellite images, we calculated normalized difference vegetation index (NDVI) to identify tsunami-impacted sites, estimate tsunami …


Transport Of Polyethylene Microplastic Spheres In A Sandy Aquifer, Alyssa Marie Graveline 2022 Northern Illinois University

Transport Of Polyethylene Microplastic Spheres In A Sandy Aquifer, Alyssa Marie Graveline

Graduate Research Theses & Dissertations

Microplastic particles are currently listed as a Contaminant of Emerging Concern (CEC) since they are in much of Earth’s water systems and recent studies indicate plastic particles can sorb toxic contaminants. Microplastics (MP) are defined as plastic particles under 5 mm in length. Currently, there is a paucity of data on the transport of MP in the subsurface. This study investigated the transport, filtration, retardation, and influence of 5-100ߎm plastic polyethylene spheres in a shallow sandy aquifer over a distance of 1m by utilizing two forced hydraulic gradient tracer studies. Slug tests were used to estimate hydraulic conductivity prior and …


Climate Change Impacts On Baseflow Contributions In A Semi-Arid, Snowmelt-Dominated Basin Within The Upper Colorado River Basin, Kaelyn Quinlan 2022 Northern Illinois University

Climate Change Impacts On Baseflow Contributions In A Semi-Arid, Snowmelt-Dominated Basin Within The Upper Colorado River Basin, Kaelyn Quinlan

Graduate Research Theses & Dissertations

The Upper Colorado River Basin (UCRB) is a significant water resource in the southwestern United States, providing water to Colorado, New Mexico, Utah, and Wyoming. (Reclamation, 2012). Communities and industries within these states are dependent on the Colorado River’s water availability and accessibility. Growing population and development demands, in conjunction with climate change, can have drastic consequences for the ecosystems and municipalities dependent on these reservoirs. It is critical that as watersheds within this region are strained under increased demands and decreased inputs, water use practices use informed decision-making to manage the budget and quality of its water resources.

I …


The Kanarra Fold-Thrust System -- The Leading Edge Of The Sevier Fold-Thrust Belt, Southwest Utah, William Joseph Michael Chandonia 2022 Missouri University of Science and Technology

The Kanarra Fold-Thrust System -- The Leading Edge Of The Sevier Fold-Thrust Belt, Southwest Utah, William Joseph Michael Chandonia

Doctoral Dissertations

“The Jurassic to Eocene Sevier fold-thrust belt is the subject of continued scientific curiosity in tectonics, stratigraphy, and industry. Understanding its development in southwest Utah is hindered in part due to the multiple origins proposed for the Kanarra anticline, a major leading edge structure -- a drag fold along the Hurricane fault, Laramide monocline, Sevier fault propagation fold, or a combination of these -- which have confused its tectonic significance and regional context. This confusion results from the structural complexity of its exposed eastern limb, as well as displacement and burial of its crest and western limb beneath Neogene sediments …


Laterally Heterogeneous Seismic Anisotropy Investigated By Shear Wave Splitting Analyses, Yan Jia 2022 Missouri University of Science and Technology

Laterally Heterogeneous Seismic Anisotropy Investigated By Shear Wave Splitting Analyses, Yan Jia

Doctoral Dissertations

"Numerous geophysical studies suggest that seismic anisotropy is a nearly ubiquitous property of the Earth’s crust and upper mantle. In this study, we utilize the shear wave splitting technique to investigate the piercing-point-dependent azimuthal anisotropy beneath the northeastern edge of the Sichuan Basin in central China, and the spatial and temporal variations of anisotropy near the 2019 M7.1 Ridgecrest earthquake in California, respectively. A clear back azimuthal dependence of the splitting parameters and the lack of a 90° or 180° periodicity of azimuthal variation in the observed fast orientations provide strong evidence for the existence of piercing-point-dependent anisotropy beneath the …


Mantle Flow And Transition Zone Discontinuities Beneath The Carribean Plate: Constraints From Shear Wave Splitting And Receiver Function Analyses, Tu Xue 2022 Missouri University of Science and Technology

Mantle Flow And Transition Zone Discontinuities Beneath The Carribean Plate: Constraints From Shear Wave Splitting And Receiver Function Analyses, Tu Xue

Doctoral Dissertations

"Azimuthal anisotropy quantified by teleseismic SKS, SKKS, PKS (“XKS”) and local S wave splitting parameters is used to investigate lithospheric deformation and asthenospheric flow beneath the boundary zone of the North American and Caribbean plates and adjacent areas. A total of 4915 XKS and 1202 pairs of local S wave splitting parameters were obtained at 24 broad band seismic stations. The XKS observations can be divided into two groups based on the spatial distribution of the resulting fast polarization orientations. Those observed on the Caribbean Plate are mostly WNW-ESE which are roughly trench-parallel. In contrast, the fast orientations observed on …


Interaction With Augmented Reality Sandbox Does Not Produce Greater Gains In Topographic Map Skills For Undergraduate Students, Celeste Kenworthy 2022 University of Nebraska - Lincoln

Interaction With Augmented Reality Sandbox Does Not Produce Greater Gains In Topographic Map Skills For Undergraduate Students, Celeste Kenworthy

Honors Program: Senior Projects (Public)

The augmented reality (AR) sandbox allows students to interact with topographic maps in a 3D space. Being able to understand topographic maps is important to geologists and they are taught in many introductory geology courses. Recent research has focused on whether the AR sandbox can improve students’ topographic map skills. Previous studies have found that students who interact with the AR sandbox do not score significantly better on topographic map assessments (TMAs) than their peers. One proposed reason for this is the limited time students have to interact with the AR sandbox. This study sought to address this by creating …


Geomorphological Change Of The Upper Yom River In Phrae Province, Kakkhanang Na Nan 2022 Faculty of Sciences

Geomorphological Change Of The Upper Yom River In Phrae Province, Kakkhanang Na Nan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Yom River is the main tributary of the Chao Phraya River; the upper Yom River flows through Phrae Province. This research selected the upper Yom River because of meander processing in an active basin, which rapidly migrates and changes landforms all the time, The object of this research is to study geomorphological change, thickness and behavior of the upper Yom River in Phrae Province. By assessing aerial photographs and satellite images from 1954 to 2019, the researchers were able to interpret the geological changes that occurred over the past 65 years. The study identified several geomorphological changes from channel migration …


Typology And Formation Of Pothole Along The Mekong River And Erosional Remnant In Sandstone Of Khorat Group, Ubon Ratchathani Province, Northeastern Thailand, Sirawat Udomsak 2022 Faculty of Sciences

Typology And Formation Of Pothole Along The Mekong River And Erosional Remnant In Sandstone Of Khorat Group, Ubon Ratchathani Province, Northeastern Thailand, Sirawat Udomsak

Chulalongkorn University Theses and Dissertations (Chula ETD)

Phachan Samphanbok Geopark showcases fascinating erosional features, such as a multitude of potholes in the Mekong River. Additionally, it is home to the largest pedestal rock in Thailand, located in Ubon Ratchathani province in the northeastern part of the country, near the border between Thailand and Laos PDR. The formation of potholes is attributed to the erosive force of swirling sediment within fractures caused by vortex currents. In this research study on pothole evolution, the potholes in the Mekong River were categorized into two main groups: structural control potholes and non-structural control potholes. These types were further divided into five …


The Derivation Of Geologic Ecosystem Services From Geodiversity In The Black Hills Region Of South Dakota And Wyoming, James Campbell Cooke 2022 University of South Dakota

The Derivation Of Geologic Ecosystem Services From Geodiversity In The Black Hills Region Of South Dakota And Wyoming, James Campbell Cooke

Dissertations and Theses

The ecosystem services approach seeks to recognize the benefits that people obtain from ecosystems, in order to highlight society’s dependence on natural systems. Ecosystem services fall into four categories: provisioning, regulating, cultural, and supporting services. Most of the ecosystem services research literature is focused on services that arise from biotic components of ecosystems. Ecosystems are dynamic complexes of biotic communities and their physical, non-living environment, interacting as a functional unit. The emphasis on biotic ecosystem services leaves understudied and undervalued the role of the abiotic, physical environment, especially in providing geologic ecosystem services. Geologic ecosystem services have been the focus …


Late Quaternary Glacier Fluctuations At Picayune Lake, Northern California, Aidan Patrick Cowan 2022 Humboldt State University

Late Quaternary Glacier Fluctuations At Picayune Lake, Northern California, Aidan Patrick Cowan

Cal Poly Humboldt theses and projects

The Klamath Mountains are a 233-km-long (north to south) mountain range located in northern California that shows extensive geomorphic evidence of Pleistocene glaciation. Within the Klamath’s there are many highland lakes, which record evidence of glacial deposition, one of which is Picayune Lake. Lake sediment data collected from Picayune Lake offers insights into the glaciation, and broader depositional history of the Picayune Lake Valley, as well as the climate history of the Klamath Mountains region. I measured magnetic susceptibility, loss on ignition, and grain size in sediment cores and used radiocarbon dating to determine a chronology of glacier fluctuations in …


Geomorphic Evaluation Of The Goose Lake Fault And Fluvial Terraces At The Yager Creek–Van Duzen River Confluence, Northern Coastal California, Samuel E. Bold 2022 Humboldt State University

Geomorphic Evaluation Of The Goose Lake Fault And Fluvial Terraces At The Yager Creek–Van Duzen River Confluence, Northern Coastal California, Samuel E. Bold

Cal Poly Humboldt theses and projects

Upper-plate deformation in the southern Cascadia subduction zone is dynamic and complex, situated in the transition between northward translation to westward convergence. Rock uplift and incision rates characteristic of this dynamic region are preserved in suites of fluvial and marine terraces. Fluvial terraces at the Yager Creek–Van Duzen River confluence record fluvial incision rates, and are crosscut by the understudied Goose Lake fault, an upper plate structure. In this work, I use high resolution lidar imagery to map terrace surfaces, and use optically stimulated luminescence, radiocarbon, and Beryllium-10 geochronology to bracket terrace ages and calculate incision and slip rates. With …


Understanding Surface Water--Groundwater Connectivity And Discharge In Arctic Deltas, Lindsey N. Aman 2022 West Virginia University

Understanding Surface Water--Groundwater Connectivity And Discharge In Arctic Deltas, Lindsey N. Aman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increased warming is driving unprecedented hydrologic changes within arctic deltas with implications for water storage, solute processing, and terrestrial and marine ecology. Thermokarst lakes within Arctic deltas store flood waters and filter solutes and sediments, thus moderating the impact of flood water discharge to arctic seas. However, this moderating influence is diminishing as lakes shrink on annual and seasonal time scales, especially close to active channels where lakes are shrinking most rapidly. This study investigates surface water-groundwater connectivity in arctic delta plains with coupled flow and heat transport models to provide a mechanistic understanding of how lake-channel proximity will impact …


Chemical Characterization Of Clastic Cave Sediments And Insights Into Particle Transport And Storage In Karst Aquifers, Jill L. Riddell 2022 West Virginia University

Chemical Characterization Of Clastic Cave Sediments And Insights Into Particle Transport And Storage In Karst Aquifers, Jill L. Riddell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Chemical characterization of clastic cave sediments and insights into particle transport and storage in karst aquifers

Jill L. Riddell

Cave sediments can be divided into two groups: precipitates and clastics. Precipitates are speleothems, or lithologic or mineral features that are chemically precipitated in the cave environment. Clastic cave sediments are frequently described by depositional facies, sorting, and particle size (Bosch and White, 2004). Robust analytical chemical analyses of these sediments to quantify their physical and chemical components is rarely performed although some chemical characterization of mineralogy and paleomagnetism has become prevalent in recent years (Chess et al., 2010; Sasowsky …


The Times, They Are A-Changin': Tracking Shifts In Mental Health Signals From Early Phase To Later Phase Of The Covid-19 Pandemic In Australia, Siqin Wang, Xiao Huang, Tao Hu, Mengxi Zhang, Zhenlong Li, Huan Ning, Jonathan Corcoran, Asaduzzaman Khan, Yan Liu, Jiajia Zhang, Xiaoming Li 2022 The University of Queensland, Australia

The Times, They Are A-Changin': Tracking Shifts In Mental Health Signals From Early Phase To Later Phase Of The Covid-19 Pandemic In Australia, Siqin Wang, Xiao Huang, Tao Hu, Mengxi Zhang, Zhenlong Li, Huan Ning, Jonathan Corcoran, Asaduzzaman Khan, Yan Liu, Jiajia Zhang, Xiaoming Li

Geosciences Faculty Publications and Presentations

Introduction Widespread problems of psychological distress have been observed in many countries following the outbreak of COVID-19, including Australia. What is lacking from current scholarship is a national-scale assessment that tracks the shifts in mental health during the pandemic timeline and across geographic contexts.

Methods Drawing on 244 406 geotagged tweets in Australia from 1 January 2020 to 31 May 2021, we employed machine learning and spatial mapping techniques to classify, measure and map changes in the Australian public’s mental health signals, and track their change across the different phases of the pandemic in eight Australian capital cities.

Results Australians’ …


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