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Full-Text Articles in Physical Sciences and Mathematics

Glass: The Material That Defines Us, Madisyn Rex Apr 2023

Glass: The Material That Defines Us, Madisyn Rex

Honors Projects

This Honors Project is an exploration of the intersections between glass science, geology, glass art, and my own personal experience with glass.


Interspecies Differences In Food Sources For The Tropical Callichirid Shrimp Neocallichirus Spp. On San Salvador Island, Bahamas, Koji Seike, H. Allen Curran Apr 2023

Interspecies Differences In Food Sources For The Tropical Callichirid Shrimp Neocallichirus Spp. On San Salvador Island, Bahamas, Koji Seike, H. Allen Curran

Geosciences: Faculty Publications

At least 4 species of callichirid shrimp coexist in the shallow marine settings of San Salvador Island, an isolated, small platform of the all-carbonates Bahama Archipelago, implying that interspecific competition or trophic niche segregation occurs between these shrimp species. Carbon and nitrogen stable isotope analyses were conducted on soft tissues of 3 callichirid species, Neocallichirus cacahuate, N. grandimana, and N. maryae, to determine the food sources for each species. These analyses revealed that the isotopic trophic niches for these 3 species do not overlap. The most important food source for all 3 species was manatee grass Syringodium filiforme …


Carbonate Microfacies Of The Middle To Upper Pennsylvanian Cache Creek Group At Meadow Lake, British Columbia, Canada, Brennen Leidy Apr 2023

Carbonate Microfacies Of The Middle To Upper Pennsylvanian Cache Creek Group At Meadow Lake, British Columbia, Canada, Brennen Leidy

Undergraduate Research Conference

No abstract provided.


Snow Distribution And Influence In Taylor Valley, Antarctica, Using Remote Sensing, Katherine Mcnulty, Peter Doran, Mark Salvatore, Suniti Karunatillake Apr 2023

Snow Distribution And Influence In Taylor Valley, Antarctica, Using Remote Sensing, Katherine Mcnulty, Peter Doran, Mark Salvatore, Suniti Karunatillake

LSU Master's Theses

The McMurdo Dry Valleys is the largest ice-free area in Antarctica, but seasonal snow covers the valley floors sporadically throughout the year. In this study, a model to estimate areal snow coverage from satellite imagery was created. An area-volume model was created to estimate the amount of snow water equivalent (SWE) from the snow area extracted from the imagery. Snow cover influences the total albedo, the hydrologic budget, and the soil moisture and soil temperature in Taylor Valley (TV). Quantifying snow precipitation in TV is challenging because snow redistributes with winds, sublimates, or melts within a short period. Previous estimates …


Evaluation Of Fluvial Package Amalgamation In Medial Dfs Deposits, Angel Peak Area, Nacimineto Formation, Sarah R. Rysanek Apr 2023

Evaluation Of Fluvial Package Amalgamation In Medial Dfs Deposits, Angel Peak Area, Nacimineto Formation, Sarah R. Rysanek

Earth and Planetary Sciences ETDs

Fluvial packages are the hypothetical groupings of facies that make up the fluvial succession consisting of channel belt sandstones and associated levee, floodplain, and avulsion deposits. This study attempted to describe a single fluvial package laterally using the new technologies of UAV imaging and 3D photogrammetry; however, amalgamation of channel belts and erosion from this amalgamation made long-distance lateral correlation difficult. This analysis of medial deposits in the Nacimiento Formation in the Angel Peak Area, Northwestern New Mexico evaluates the degree of amalgamation of fluvial packages across the study area while identifying facies associated with the hypothetical fluvial package. This …


Alfred Russel Wallace Notes 25. Wallace And The 'Physical Environment'., Charles H. Smith Apr 2023

Alfred Russel Wallace Notes 25. Wallace And The 'Physical Environment'., Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace’s natural selection essay of 1858 has been held to frame a greater role for the physical environment in forcing selection regimes than we find in Darwin’s writings, but here that verdict is challenged by a re-examination of both the essay itself, and period usage of the term ‘physical.’


Stratigraphic Architecture Of Pozuelo Mounds As Revealed By Earth Resistivity Tomography, Caeli Connolly Apr 2023

Stratigraphic Architecture Of Pozuelo Mounds As Revealed By Earth Resistivity Tomography, Caeli Connolly

Honors College

This study is a geoarchaeological analysis using earth resistance tomography (ERT) surveys of two of four mounds at Pozuelo (Formative Period, cal yr 3000 BP) in the Chincha Valley of coastal, southern Peru. Layers identified in the subsurface were to determine the presence or absence of regional continuity between the mounds. This effort is part of a larger investigation examining the paleoenvironmental setting of the site, and its influence on site location and use. Ten earth resistance tomography profiles were collected using an ABEM Terrameter LS2 and 81 pin array. These profiles were then topographically corrected using topographic survey data …


Using Mineral Magnetism To Characterize Compositions Of Fe-Ti Oxide Phases Of The Sulphur Creek Lava Flow (Kulshan), Elika Zilis Apr 2023

Using Mineral Magnetism To Characterize Compositions Of Fe-Ti Oxide Phases Of The Sulphur Creek Lava Flow (Kulshan), Elika Zilis

WWU Honors College Senior Projects

The aim of this study is to examine variations in the composition of Fe-Ti oxide minerals in the Sulphur Creek lava flow (SE margin of Kulshan), using magnetic techniques and electron microscopy. Geochemical and petrological data from these rocks dated ~9.8 ka may be a product of two distinct magma pulses (Garvey, 2002) with two distinct compositions: andesitic basalt and basalt. The composition of cubic oxides (magnetite and ulvöspinel) is influenced by the geochemistry of the crystallizing magma and can be used to provide information about the chemical evolution of these magmas, but also to help frame future paleomagnetic studies …


Dust Production And Transport In A Long-Lived Fluvial-Eolian System In The Pampas Of South America, Blake Marcus Stubbins Apr 2023

Dust Production And Transport In A Long-Lived Fluvial-Eolian System In The Pampas Of South America, Blake Marcus Stubbins

Theses and Dissertations

Wind-blown dust from southern South America links the terrestrial, marine, atmospheric, and biologic components of Earth’s climate system. The Pampas of central Argentina (~33-40° S) contain an extensive upper Miocene to Holocene eolian record that spans the relatively warm conditions of the Late Miocene to cooler climates of the Plio-Pleistocene and Holocene. We collected 13 loess, paleosol, and fluvial samples from the upper Miocene Cerro Azul and Rio Negro Formations which resulted in n = 5129 new detrital zircon U-Pb ages. Late Miocene rivers conveyed sediment from northern Patagonia, the Andes adjacent to the Pampas, and the Sierras Pampeanas to …


Exploring The Current Training Of Undergraduate Geology Students And Teaching Spatial Skills To Improve Student Outcomes, Ann Marie Klyce Apr 2023

Exploring The Current Training Of Undergraduate Geology Students And Teaching Spatial Skills To Improve Student Outcomes, Ann Marie Klyce

Theses and Dissertations

Spatial skills, which represent the ability to mentally manipulate objects (Schneider & McGrew, 2012; Atit et al., 2020) have been shown to be correlated with entrance, persistence and success in STEM (Shea et al., 2001; Wai et al., 2009). Specifically, these skills have been shown to be necessary to geologists and geoscientists (Hegarty, 2014; Gagnier et al., 2016). While we recognize the importance of these skills, explicit training in them is rarely offered (NRC 2006). Consequently, cognitive scientists and discipline based education researchers have begun concerted efforts to offer training in spatial skills to improve student outcomes (e.g. Uttal et …


A Seismic Investigation Of Uturuncu Volcano And The Lazufre Volcanic Complex, Heather L. Mcfarlin Mar 2023

A Seismic Investigation Of Uturuncu Volcano And The Lazufre Volcanic Complex, Heather L. Mcfarlin

USF Tampa Graduate Theses and Dissertations

The following dissertation is a study of three seismological techniques used to determine the geophysical properties of two large, inflating magma bodies in the upper crust in South America: one under Uturuncu volcano and one beneath Lastarria and Cordon del Azufre volcanoes. First, I use the method of teleseismic receiver functions to image the top and bottom of the magma body beneath Uturuncu volcano. Depths to the top of this body vary between 6 and 12 km below sea level, while depths to the bottom vary between 13 and 22 km below sea level, with the thickness ranging from 6 …


2021 Particle Grain-Size And Total Organic Content Analyses Of Surface Sediments From Puget Sound And Elliott Bay Near Seattle, Wa, Ethan Hoang Mar 2023

2021 Particle Grain-Size And Total Organic Content Analyses Of Surface Sediments From Puget Sound And Elliott Bay Near Seattle, Wa, Ethan Hoang

Environmental Science Undergraduate Theses

Seattle’s Elliott Bay has been a particularly intriguing area in regards to anthropological activities and their effects on the surrounding environment. The construction of the city brought about the displacement of sediment around the bay, resulting in lower quality sediments that negatively impact the nutrient cycles in the benthic zone. This project’s examination of total organic carbon and particle size in sediment serves as a baseline to which scientists can refer in monitoring future sediment health. To determine this baseline, UW Tacoma obtained sediment samples from Washington State Department of Ecology’s Puget Sound Ecosystem Monitoring Program. The samples were analyzed …


New Surficial Geologic Mapping In Kentucky (2021-2022), Matthew Massey, Antonia Bottoms, Max Hammond Iii, Ann Hislop, Meredith Swallom, Michele M. Mchugh Mar 2023

New Surficial Geologic Mapping In Kentucky (2021-2022), Matthew Massey, Antonia Bottoms, Max Hammond Iii, Ann Hislop, Meredith Swallom, Michele M. Mchugh

Research Data--KGS

New surficial geologic mapping was performed in nine new 7.5-minute quadrangles in Hardin, Meade, Breckinridge, Grayson, Hart, and Larue Counties, Kentucky.

Quadrangles include Big Clifty, Big Spring (Hardin county only), Custer (Hardin County only), Flaherty, Madrid (Hardin county only), Millerstown, Summit, Tonieville (Hardin county only), and Upton.

Mapping data for each of the nine quadrangles is captured in a ZIP file that contains an ESRI geodatabase and associated FGDC-compliant metadata files (.xml).

The geodatabase is a relational geodatabase of spatial and non-spatial data that conforms to "GeMS (Geologic Map Schema)--a standard format for digital publication of geologic maps", available at …


Kentucky Geological Survey Landslide Inventory [2023-03], Matthew M. Crawford Mar 2023

Kentucky Geological Survey Landslide Inventory [2023-03], Matthew M. Crawford

Research Data--KGS

The KGS landslide inventory provides the locations of known landslides and areas susceptible to debris flows. Various types of landslides are represented including slides, flows, rockfalls, and creep. The data are available as ArcGIS geodatabase feature classes. Landslide locations and associated attributes are compiled from Kentucky Geological Survey research, published maps, state and local government agencies, the public, and media reports. A confidence ranking system assigns a value to each feature. A description of the feature classes is here: https://kgs.uky.edu/kgsmap/helpfiles/landslide_help.shtm

The inventory viewed in a GIS with geology, soils, slope or other terrain-based data can serve as a basis for …


Are Natural Fractures In Sandstone Reservoir: Water Wet – Mixed Wet – Or Oil Wet?, Salah Almudhhi, Laila Abdullah, Waleed Al-Bazzaz, Saleh Alsayegh, Hussien Alajaj, Ralph E. Flori Mar 2023

Are Natural Fractures In Sandstone Reservoir: Water Wet – Mixed Wet – Or Oil Wet?, Salah Almudhhi, Laila Abdullah, Waleed Al-Bazzaz, Saleh Alsayegh, Hussien Alajaj, Ralph E. Flori

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This study accurately measures the wettability contact angle of native Kuwaiti sandstone reservoir that hosts mixed pore size distributions in both the tight sandstone matrix as well as the natural fracture (NF) embedded in it. Also, this study, effectively, investigates the geometrical size and shape of natural available voids whether matrix voids or NF voids captured in the rock 2D image frame system. Correspondingly, this study is, successfully, measure tight matrix, NF Pore wall, and NF pore opening wettability performance and recovery efficiency contributions inside the sandstone reservoir. A model pore/ grain contact angle wettability is generated. Therefore, this study …


Nebraska Statewide Groundwater-Level Monitoring Report 2022, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Jeffrey Westrop Mar 2023

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

No abstract provided.


Late Neoarchean To Middle Paleoproterozoic Geology Of Devon And Ellesmere Islands, Canadian Arctic, Joshua P. Laughton Feb 2023

Late Neoarchean To Middle Paleoproterozoic Geology Of Devon And Ellesmere Islands, Canadian Arctic, Joshua P. Laughton

Electronic Thesis and Dissertation Repository

The northernmost exposure of the Laurentian shield in Canada outcrops on Devon and Ellesmere islands within the Canadian Arctic Archipelago. Due to the remote location, the basement rocks of these islands have received little attention. From this study, zircon crystallization ages demonstrate that Devon Island is underlain by a late Neoarchean terrane comprising orthogneisses emplaced at ca. 2.55–2.51 Ga and an interleaved metasedimentary sequence deposited at ca. ≥2.47 Ga. On northern Devon Island, younger metasedimentary sequence(s) were deposited at ca. 2.2–1.9 Ga and intruded by ca. 2.01–1.95 Ga granitoids. Devon and Ellesmere islands experienced widespread metamorphic activity associated with the …


Picture Gorge Basalt: Internal Stratigraphy, Eruptive Patterns, And Its Importance For Understanding Columbia River Basalt Group Magmatism, Emily Bogdan Cahoon, Martin J. Streck, Anthony A.P. Koppers Feb 2023

Picture Gorge Basalt: Internal Stratigraphy, Eruptive Patterns, And Its Importance For Understanding Columbia River Basalt Group Magmatism, Emily Bogdan Cahoon, Martin J. Streck, Anthony A.P. Koppers

Geology Faculty Publications and Presentations

The Picture Gorge Basalt (PGB) of the Columbia River Basalt Group (CRBG) has been previously thought to be limited in its eruptive volume (<3000 >km3) and thought to not extend far from its type locality. At present, PGB represents only 1.1 vol% of the CRBG with a relatively limited spatial distribution of ~10,000 km2. New age data illustrate that the PGB is the earliest and longest eruptive unit compared to other main-phase CRBG formations and that some dated basaltic flows reach far (~100 km) beyond the previously mapped extent. This study focuses on extensive outcrops of …


Coral Gardens Reef, Belize: An Acropora Spp. Refugium Under Threat In A Warming World, Lisa Greer, H. Allen Curran, Karl Wirth, Robert Humston, Ginny Johnson, Lauren Mcmanus, Candice Stefanic, Tara Clark, Halard Lescinsky, Kirah Forman-Castillo Feb 2023

Coral Gardens Reef, Belize: An Acropora Spp. Refugium Under Threat In A Warming World, Lisa Greer, H. Allen Curran, Karl Wirth, Robert Humston, Ginny Johnson, Lauren Mcmanus, Candice Stefanic, Tara Clark, Halard Lescinsky, Kirah Forman-Castillo

Geosciences: Faculty Publications

Live coral cover has declined precipitously on Caribbean reefs in recent decades. Acropora cervicornis coral has been particularly decimated, and few Western Atlantic Acropora spp. refugia remain. Coral Gardens, Belize, was identified in 2020 as a long-term refugium for this species. This study assesses changes in live A. cervicornis coral abundance over time at Coral Gardens to monitor the stability of A. cervicornis corals, and to explore potential threats to this important refugium. Live coral cover was documented annually from 2012– 2019 along five permanent transects. In situ sea-surface temperature data were collected at Coral Gardens throughout the study period …


The Fate Of Carbonate Rocks During Hypervelocity Impacts: Case Studies From Three Impact Structures On Earth, Nicolas D. Garroni Feb 2023

The Fate Of Carbonate Rocks During Hypervelocity Impacts: Case Studies From Three Impact Structures On Earth, Nicolas D. Garroni

Electronic Thesis and Dissertation Repository

Approximately 28% of all hypervelocity impact structures discovered on Earth exist in a carbonate-dominated target sequence. Despite decades of research, how carbonate rocks and minerals react to shock metamorphism is still poorly understood. In this contribution, three impact structures on Earth were studied to determine the effects of shock metamorphism on carbonate minerals: Chicxulub, Crooked Creek and Jebel Waqf as Suwwan.

At Chicxulub, carbonates from the impact-melt bearing breccia of drill core, M0077A were characterized petrographically and geochemically. Calcite was the only carbonate mineral present and is abundant throughout the impact breccia in five distinct varieties: limestone clasts …


Seismic Azimuthal Anisotropy Beneath A Fast Moving Ancient Continent: Constraints From Shear Wave Splitting Analysis In Australia, Kailun Ba, Stephen S. Gao, Jianguo Song, Kelly H. Liu Feb 2023

Seismic Azimuthal Anisotropy Beneath A Fast Moving Ancient Continent: Constraints From Shear Wave Splitting Analysis In Australia, Kailun Ba, Stephen S. Gao, Jianguo Song, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Seismic Azimuthal Anisotropy Beneath Australia is Investigated using Splitting of the Teleseismic PKS, SKKS, and SKS Phases to Delineate Asthenospheric Flow and Lithospheric Deformation Beneath One of the Oldest and Fast-Moving Continents on Earth. in Total 511 Pairs of High-Quality Splitting Parameters Were Observed at 116 Seismic Stations. Unlike Other Stable Continental Areas in Africa, East Asia, and North America, Where Spatially Consistent Splitting Parameters Dominate, the Fast Orientations and Splitting Times Observed in Australia Show a Complex Pattern, with a Slightly Smaller Than Normal Average Splitting Time of 0.85 ± 0.33 S. on the North Australian Craton, the Fast …


Extreme Differentiation Along Multiple Liquid Lines Of Descent In Strongly Peralkaline Magma Series At Pantelleria (Italy), John C. White, Ray Macdonald, Bogusław Bagiński, Katarzyna M. Liszewska Feb 2023

Extreme Differentiation Along Multiple Liquid Lines Of Descent In Strongly Peralkaline Magma Series At Pantelleria (Italy), John C. White, Ray Macdonald, Bogusław Bagiński, Katarzyna M. Liszewska

EKU Faculty and Staff Scholarship

The liquid line of descent from trachyte to pantellerite is controlled primarily by fractional crystallization of alkali feldspar, with whole rock compositions following a fractionation path along the ‘thermal valley’ in the peralkaline haplogranite system Qz-Ab-Or-Ac-Ns and terminating at a minimum on the feldspar-quartz cotectic. Although whole-rock compositions for different pantelleritic suites follow nearly identical paths in a Qz-Ab-Or projection that terminate near the experimental minimum (Qz40.5Or34.5Ab25 at 100 MPa, projected from Ac-Ns), matrix glass from samples with near-minimum compositions record extreme differentiation and form a ‘cotectic delta’ beyond the terminus of the ‘thermal valley’. Although each glass trend shows …


The Use And Challenges Of Spatial Data In Archaeology, Carla Klehm Feb 2023

The Use And Challenges Of Spatial Data In Archaeology, Carla Klehm

Anthropology Faculty Publications and Presentations

Spatial data, under the broader umbrella of digital data, is becoming increasingly integral to all stages of archaeological research design and dissemination. As archaeologists lean toward reuse and interoperability, with ethics on their minds, how to treat spatial data is of particular importance. This is because of the complexities involved at every life-cycle stage, from collection to publication, including black box issues that may be taken for granted, and because the size of spatial data can lead to archiving difficulties. Here, the “DIY” momentum of increasingly accessible spatial methods such as photogrammetry and handheld lidar is examined alongside forthcoming changes …


Columbia River Rhyolites: Age-Distribution Patterns And Their Implications For Arrival, Location, And Dispersion Of Continental Flood Basalt Magmas In The Crust, Martin J. Streck, Vanessa M. Swenton, William C. Mcintosh, Matt Heizler Jan 2023

Columbia River Rhyolites: Age-Distribution Patterns And Their Implications For Arrival, Location, And Dispersion Of Continental Flood Basalt Magmas In The Crust, Martin J. Streck, Vanessa M. Swenton, William C. Mcintosh, Matt Heizler

Geology Faculty Publications and Presentations

Columbia River province magmatism is now known to include abundant and widespread rhyolite centers even though the view that the earliest rhyolites erupted from the McDermitt Caldera and other nearby volcanic fields along the Oregon–Nevada state border has persisted. Our study covers little-studied or unknown rhyolite occurrences in eastern Oregon that show a much wider distribution of older centers. With our new data on distribution of rhyolite centers and ages along with literature data, we consider rhyolites spanning from 17.5 to 14.5 Ma of eastern Oregon, northern Nevada, and western Idaho to be a direct response to flood basalts of …


Looking Backward And Forward: Volcanology In The Years 2000, 2010, 2020, And Beyond, Jonathan Fink, Katharine Cashman Jan 2023

Looking Backward And Forward: Volcanology In The Years 2000, 2010, 2020, And Beyond, Jonathan Fink, Katharine Cashman

Geology Faculty Publications and Presentations

Figuring out how volcanoes work is one of the geoscience’s most complex puzzles. Clues of all sizes, shapes, and colors are scattered across every continent, the bottom of the ocean, in the atmosphere, and on the surfaces of other planets. Generations of geologists, geophysicists, geodesists, and geochemists have used field observations, laboratory measurements, and theory to fill gaps left by their predecessors. Yet critical uncertainties remain. Why do eruptions begin? What determines their intensity? What controls their frequency and style of activity? What causes them to end? These unsolved issues leave society increasingly vulnerable to volcanic disruptions. Hundreds of published …


The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan Jan 2023

The Kanarra Fold-Thrust Structure - The Leading Edge Of The Sevier Fold-Thrust Belt, Southwestern Utah: Geology Of The Intermountain West, William J. Chandonia, John P. Hogan

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The multiple origins proposed for the Kanarra anticline in southwestern Utah as a drag-fold along the Hurricane fault, a Laramide monocline, a Sevier fault-propagation fold, or a combination of these process­es, serve to muddy its tectonic significance. This in part reflects the structural complexity of the exposed eastern half of the fold. The fold evolved from open and up-right to overturned and tight, is cross-cut by multiple faults, and was subsequently dismembered by the Hurricane fault. The western half of the fold is obscured because of burial, along with the hanging wall of the Hurricane fault, beneath Neogene and younger …


Abdoo, Mary, 1913-1990 (Sc 3668), Manuscripts & Folklife Archives Jan 2023

Abdoo, Mary, 1913-1990 (Sc 3668), Manuscripts & Folklife Archives

Manuscript Collection Finding Aids

Finding aid and scan (Click on "Additional Files" below) for Manuscripts Small Collection 3668. “The Elk Horn Coal Corporation,” by Mary Abdoo. The 1935 report examines Elkhorn coal as well as the corporation’s history, officers, and financial status. Includes a letter from the author outlining the company’s approval of the report.


Linking The Pinware, Baraboo, And Picuris Orogens: Recognition Of A Trans-Laurentian Ca. 1520–1340 Ma Orogenic Belt, Christopher G. Daniel, Aphrodite Indares, L. Gordon Medaris Jr., Ruth Aronoff, David H. Malone, Joshua Schwartz Jan 2023

Linking The Pinware, Baraboo, And Picuris Orogens: Recognition Of A Trans-Laurentian Ca. 1520–1340 Ma Orogenic Belt, Christopher G. Daniel, Aphrodite Indares, L. Gordon Medaris Jr., Ruth Aronoff, David H. Malone, Joshua Schwartz

Faculty Publications-- Geography, Geology, and the Environment

It is proposed that the Pinware orogen of eastern Canada, the Baraboo orogen of the midcontinent, and the Picuris orogen of the southwestern United States delineate a previously unrecognized, ~5000-km-long, ca. 1520–1340 Ma trans-Laurentian orogenic belt. All three orogenic provinces are characterized by Mesoproterozoic sedimentation, magmatism, metamorphism, and deformation—the hallmarks of a tectonically active plate margin. Tectonism was diachronous, with the earliest stages beginning ca. 1520 Ma in eastern Canada and ca. 1500 Ma in the southwest United States. Magmatic zircon age distributions are dominated by Mesoproterozoic, unimodal to multimodal age peaks between ca. 1500 and 1340 Ma. The onset …


Reconnaissance Of Landslides And Debris Flows Associated With The July 2022 Flooding In Eastern Kentucky, Matt M. Crawford, Zhenming Wang, Seth Carpenter, Jonathan Schmidt, Hudson J. Koch, Jason M. Dortch Jan 2023

Reconnaissance Of Landslides And Debris Flows Associated With The July 2022 Flooding In Eastern Kentucky, Matt M. Crawford, Zhenming Wang, Seth Carpenter, Jonathan Schmidt, Hudson J. Koch, Jason M. Dortch

Report of Investigations--KGS

Between July 25 and July 30, 2022, a series of convective storms generated approximately 14–16 inches of rainfall across parts of eastern Kentucky, predominately in Clay, Leslie, Perry, Breathitt, Knott, and Letcher Counties. The peak rainfall occurred on the evening of July 27 and the morning of July 28, with the hardest-hit areas experiencing more than 10 inches in a 24-hour period. The historic rainfall led to catastrophic flooding along many rivers and streams, but also triggered widespread landslides and debris flows that damaged roads, homes, property, and other infrastructure. Once initial relief and recovery efforts were established, the Kentucky …


Cementation And Groundwater Chemistry In Pleistocene Paleodune Deposits Of The Central Oregon Coast, Adrienne Lynn Stephens Jan 2023

Cementation And Groundwater Chemistry In Pleistocene Paleodune Deposits Of The Central Oregon Coast, Adrienne Lynn Stephens

Dissertations and Theses

Pleistocene paleodune deposits occur along the Oregon coast, underlying coastal towns, roadways, and associated power and water infrastructure(s). Secondary cementation within these deposits provides some stability, allowing for near-vertical sea cliffs and roadcut outcrops. Yet, slope instability is a prevalent hazard observed within the paleodune deposits. Weakening of cementing agents via changes to groundwater conditions due to altered vegetation, climate change, or contamination, for example, could promote slope instability, threatening lives and infrastructure. This study aims to investigate the variability in the type and degree of cementation and to determine how they are affected by changes in groundwater conditions.

To …