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2023

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Articles 271 - 300 of 304

Full-Text Articles in Geology

Integrating Lidar, Aeromagnetic, And Geological Field Data To Identify Structural-Lithologic Elements Within The Archean Carney Lake Gneiss Complex, Ian M. Gannon Jan 2023

Integrating Lidar, Aeromagnetic, And Geological Field Data To Identify Structural-Lithologic Elements Within The Archean Carney Lake Gneiss Complex, Ian M. Gannon

Dissertations, Master's Theses and Master's Reports

The Archean Carney Lake Gneiss Complex (CLGC) is a suite of rocks on the southern margin of the Superior Province and within the Minnesota River Valley subprovince. It is one of many gneissic domes in Michigan, Wisconsin, and Minnesota whose complex geology is poorly understood due to a previous lack of economic interest in gneissic terranes and significant challenges to their investigation. As a consequence, the CLGC and other gneissic domes in the region are represented on geologic maps as undifferentiated masses surrounded by better defined and understood Paleoproterozoic supracrustal rocks and igneous intrusions. Within the last ten years, however, …


Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 1, Peter-Jon A. Waddell, Paul Galloway Jan 2023

Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 1, Peter-Jon A. Waddell, Paul Galloway

Technical Bulletins

This technical bulletin defines and maps the land resources of the southern Goldfields region of Western Australia (WA). The southern Goldfields region, as featured in this bulletin, covers 151,753 km2. The western and eastern borders are variable because they align with various cadastral boundaries. The western survey border, which in part follows the WA State Barrier Fence, demarcates cleared agricultural land from the intact, western extent of the Great Western Woodlands. The eastern border abuts the westernmost Nullarbor pastoral lease boundaries, except for the north-easternmost and south-easternmost edges which continue into Crown land. Major towns are Coolgardie, Kalgoorlie …


Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 2, Peter-Jon A. Waddell, Paul Galloway Jan 2023

Land Systems, Soils And Vegetation Of The Southern Goldfields And Great Western Woodlands Of Western Australia - Volume 2, Peter-Jon A. Waddell, Paul Galloway

Technical Bulletins

This technical bulletin defines and maps the land resources of the southern Goldfields region of Western Australia (WA). The southern Goldfields region, as featured in this bulletin, covers 151,753 km2. The western and eastern borders are variable because they align with various cadastral boundaries. The western survey border, which in part follows the WA State Barrier Fence, demarcates cleared agricultural land from the intact, western extent of the Great Western Woodlands. The eastern border abuts the westernmost Nullarbor pastoral lease boundaries, except for the north-easternmost and south-easternmost edges which continue into Crown land. Major towns are Coolgardie, Kalgoorlie …


Hydrogeologic Field Trip Of Northeast Nebraska, Sue Olafsen Lackey, Kathleen Cameron, Matt Marxsen Jan 2023

Hydrogeologic Field Trip Of Northeast Nebraska, Sue Olafsen Lackey, Kathleen Cameron, Matt Marxsen

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


2023 Nebraska Water Leaders Academy, Mark E. Burbach, Robert Matthew Joeckel Jan 2023

2023 Nebraska Water Leaders Academy, Mark E. Burbach, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

Eighteen participants completed the 2023 Water Leaders Academy bringing the total number of graduates to 186 since the inception of the program in 2011. Assessments of participants’ transformational leadership skills, champion of innovation skills, water knowledge, engagement with water issues, civic capacity, entrepreneurial leadership behaviors, boundary spanning skills, and curiosity increased significantly over the course of the year, according to both the participants and their raters. Feedback from the participants was highly positive and constructive. Academy planners are addressing participant concerns. Results of the program assessment indicate that the curriculum is meeting the Academy’s objectives. Therefore, only minor changes are …


Telescopic Megafans On The High Plains, Usa Were Signal Buffers In A Major Source-To-Sink System, Jesse T. Korus Dr., Robert Matthew Joeckel Jan 2023

Telescopic Megafans On The High Plains, Usa Were Signal Buffers In A Major Source-To-Sink System, Jesse T. Korus Dr., Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


3d Hydrostratigraphic And Hydraulic Conductivity Modeling Using Supervised Machine Learning, T. A. Tilahun, Jesse T. Korus Dr. Jan 2023

3d Hydrostratigraphic And Hydraulic Conductivity Modeling Using Supervised Machine Learning, T. A. Tilahun, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Nebraska's Water, Nawaraj Shrestha, Ann Briggs, Aaron R. Young, Robert Matthew Joeckel Jan 2023

Nebraska's Water, Nawaraj Shrestha, Ann Briggs, Aaron R. Young, Robert Matthew Joeckel

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Conservation And Survey Division 2023 Annual Report, R. M. Joeckel, M. M. Waszgis Jan 2023

Conservation And Survey Division 2023 Annual Report, R. M. Joeckel, M. M. Waszgis

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Analysis Of Chemical Elements In Basalts Using Mislabeled Data, A Machine Learning Approach, Jenifer Vivar Jan 2023

Analysis Of Chemical Elements In Basalts Using Mislabeled Data, A Machine Learning Approach, Jenifer Vivar

Dissertations and Theses

Scientists use basalt chemistry to discriminate among different tectonic settings. There are well-known chemical elements used to classify tectonic settings. An exploration of new features is done using Logistic Regression and Random Forest to discover any new elements of interest. The models were used with other tools, such as recursive feature elimination and permutations, to increase reliability. Among the scarcely explored chemical elements are Terbium (Tb), Holmium (Ho), Samarium (Sm), and Erbium (Er). The data used for the exploration contained many outliers. Therefore, an ensemble model was created to explore the location and composition of such outliers. The ensemble was …


Physicochemical Constraints To Melts From Láscar Volcano Recorded By Syn-Eruptive Apatite, Cesar Andres Bucheli Olaya Jan 2023

Physicochemical Constraints To Melts From Láscar Volcano Recorded By Syn-Eruptive Apatite, Cesar Andres Bucheli Olaya

Graduate Theses/Dissertations

Geochemical microanalysis of apatite crystals was conducted to model the composition and thermodynamic conditions of melts involved in explosive eruptions at Láscar volcano (NE Chile). Apatite crystals were extracted from representative samples of Láscar’s eruptive stages II (Soncor ignimbrite), III (Tumbres scoria deposit), and IV (1993 CE pumice). I used electron microprobe analysis, laser ablation - inductively coupled plasma mass spectrometry, and secondary ionization mass spectrometry to generate quantitative compositional maps and gather data of major, trace, and volatile element contents in crystals. Major and trace-element behavior in Láscar apatites reflects general whole-rock compositional trends of Láscar and other Andean …


Magmatic Evolution Of The Chasca Orkho Lava Series And Its Magmatic Enclaves, Volcán Ollagüe, Central Andes, Nathaniel W. Lenhard Jan 2023

Magmatic Evolution Of The Chasca Orkho Lava Series And Its Magmatic Enclaves, Volcán Ollagüe, Central Andes, Nathaniel W. Lenhard

Graduate Theses/Dissertations

Magma mixing is a common factor in the creation of intermediate composition magmas and a potential instigator of a volcanic eruption. Magmatic enclaves, physical evidence of magma mixing within a volcanic system, are a phenomenon whose mechanisms remain unclear and debated. Common hypotheses explaining the occurrence of magmatic enclaves within a host lava range from the repeated injection of a new magma into a shallow reservoir to the disruption of equilibrium within a stratified magma chamber. Within the Andean Central Volcanic Zone (CVZ), the occurrence of magmatic enclaves yields similar geochemical compositions to their respective host rocks, bringing more difficulty …


Historical Channel Evolution And Human Modifications Of Blue River Near Kansas City Missouri, Katie Ann Grong Jan 2023

Historical Channel Evolution And Human Modifications Of Blue River Near Kansas City Missouri, Katie Ann Grong

Graduate Theses/Dissertations

Channel form can respond to changes in flood regime and sediment load caused by land use and climate disturbances. In the eastern United States, widespread soil and vegetation disturbances in the 1800s during agricultural expansion increased runoff rates, flood magnitude and frequency, and sediment loads often causing major changes in channel activity and floodplain sedimentation in local streams. Investigating the historical evolution of a stream channel system including its floodplains can help to advance geomorphological theory and benefit environmental managers. This study documents human impacts on historical changes in channel and floodplain widths since the early to middle 1800s in …


Methods For Investigating Geo-Stem Learning Ecosystems: A Case-Study Of Illinois Earth Science Teachers, Cheryl L.B. Manning Jan 2023

Methods For Investigating Geo-Stem Learning Ecosystems: A Case-Study Of Illinois Earth Science Teachers, Cheryl L.B. Manning

Graduate Research Theses & Dissertations

The complex interactions between people and resources in communities that foster innovation can be thought of as ecosystems. These ecosystems have the potential to broaden participation in the geoscience community if we invest in collaborations that map out long-term solutions and career pathways for young community members. Geo-STEM learning ecosystems (GLE) engage local communities in sustainable programs that promote geoscience literacy and inspire people to learn the geosciences. A goal of GLE is to leverage existing social systems and accelerate geo-STEM solutions for society. Thus far, few studies in the geosciences have interrogated what is meant by a “learning ecosystem” …


Influence Of Land Use, Precipitation, And Seasonality On Surface Water Quality In The East And Upper South Branches Of The Kishwaukee River Watershed (Esbkr), Ashley Irene Broussard Jan 2023

Influence Of Land Use, Precipitation, And Seasonality On Surface Water Quality In The East And Upper South Branches Of The Kishwaukee River Watershed (Esbkr), Ashley Irene Broussard

Graduate Research Theses & Dissertations

The East and Upper South Branches of the Kishwaukee River Watershed (ESBKR) are two HUC-10 watersheds that cover approximately 221.8 mi2 (574.5 km2) in north-central Illinois. Segments of the Kishwaukee River within the ESBKR are in the ILEPA’s 303(d) list of impaired waters for fish consumption and aesthetic quality. To protect and improve stream health, we must better understand the impact of diverse land use on non-point source (NPS) pollution and water quality. The primary goal of this study was to determine how different land uses impact the surface water quality within the ESBKR. To address this goal, surface water …


Continental Saline Environments Interpreted From Bedded Gypsum Of The Triassic Red Peak Formation (Chugwater Group), Northcentral Wyoming, Maya Yamei Bradford Jan 2023

Continental Saline Environments Interpreted From Bedded Gypsum Of The Triassic Red Peak Formation (Chugwater Group), Northcentral Wyoming, Maya Yamei Bradford

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bedded evaporites and associated red bed siliciclastics record saline lake and groundwater systems from Permo-Triassic Pangea. A major component of these red bed and evaporite systems is bedded gypsum. However, little attention has been paid to the textures of ancient gypsum. Observations of gypsum textures can refine interpretations of depositional environment and diagenetic history. This project describes textures of bedded gypsum from an outcrop of the Triassic Red Peak Formation (Chugwater Group) near Greybull, Wyoming.

This thesis uses fieldwork, petrography, and x-ray diffraction to describe an outcrop of the upper Red Peak Formation, with a focus on textures of bedded …


Bibliography, Leslie North Jan 2023

Bibliography, Leslie North

Faculty/Staff Personal Papers

Bibliography of publications by Leslie North.


Applied Geochemistry, Geochronology And Biostratigraphy: Case Studies From The 38th Parallel Structures In Missouri And Orange Basin, Offshore Western South Africa, Marissa Kay Spencer Jan 2023

Applied Geochemistry, Geochronology And Biostratigraphy: Case Studies From The 38th Parallel Structures In Missouri And Orange Basin, Offshore Western South Africa, Marissa Kay Spencer

Doctoral Dissertations

"The unique alignment of the Decaturville, Crooked Creek, and Weaubleau geological structures in central Missouri, three of nine known such structures along the 38th parallel in Illinois, Missouri, and Kansas, has puzzled geoscientists for decades. Research using palynology (palynomorphs and particulate organic matter) and radiometric dating of impact spherules were used to constrain age and a relationship between these enigmatic structures and infer their paleoenvironmental conditions. Novel melting damages, unique to impact, were documented in the palynomorphs in all the three structures. Early Ordovician acritarchs with melted processes correlate with 40Ar-39Ar stepwise heating age of impact spherules …


Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh Jan 2023

Petrological And Geochemical Evaluation Of Rare-Earth Element Potential In The Sparta Granite Complex, Max J. Eshbaugh

Honors College Theses

Rare earth elements (REEs) are important resources with applications in the electronics, renewable energy, and automotive industries. REEs may be concentrated in the residual weathered portion of igneous parent rocks, typically granites. These residual deposits are mined in southeast Asia, but analogous climatic and geologic conditions suggest the existence of economically viable REE residual deposits in the southeastern United States (U.S.). The Sparta Granite Complex in east-central Georgia is a granitoid complex emplaced at the end of the Alleghanian orogeny, forming a suture between the Savannah River and Milledgeville terranes. Petrologic and geochemical assessments of the Sparta Granite and overlying …


Structure, Construction, And Emplacement Of The Northern Margin Of The Late Cretaceous Sonora Pass Intrusive Suite: North-Central Sierra Nevada Batholith, California, Victoria A. Arnold Jan 2023

Structure, Construction, And Emplacement Of The Northern Margin Of The Late Cretaceous Sonora Pass Intrusive Suite: North-Central Sierra Nevada Batholith, California, Victoria A. Arnold

Master's Theses

Of the four voluminous, normally zoned Late Cretaceous intrusive suites of the Sierra Nevada batholith, the >1,000 km², ~96-88 Ma Sonora Pass intrusive suite is the oldest, northernmost, and least studied. It contains the marginal, equigranular Kinney Lakes hornblende-biotite granodiorite and the inner, porphyritic Topaz Lake biotite granodiorite. From this research, the Lake Alpine granodiorite is now considered the outermost part of the Sonora Pass intrusive suite. The suite intruded Early Cretaceous plutons and metasedimentary rocks. The Kinney Lakes and Lake Alpine granodiorites were constructed by multiple phases, as were the plutonic host rocks. The granodiorites are marked by schlieren …


Melt Inclusion Record Of Submarine Caldera Formation On Axial Seamount, Juan De Fuca Ridge, Destiny Kapule Jan 2023

Melt Inclusion Record Of Submarine Caldera Formation On Axial Seamount, Juan De Fuca Ridge, Destiny Kapule

Master's Theses

This study contributes to understanding magmatic processes and the plumbing system of submarine volcanoes before, during, and after caldera formation with the use of melt inclusions (MIs). Major, trace and volatile geochemistry from both olivine and plagioclase-hosted MIs taken from volcaniclastic deposits around Axial Seamount reveal information about the storage conditions, ascent rates and eruption styles of magmas. Magma crystallizes in the subsurface, capturing MIs, and ascends where some host glasses may interact with seawater during eruption. Oversaturation in volatiles and low vesicularity show quick ascent rates. By analyzing chemical data within a pre-existing stratigraphic context this study can assess …


Sedimentological Characteristics Of Storm Deposits Induced By The Tropical Storm Pa Buk Along The Western Coast Of The Gulf Of Thailand, Chanakan Ketthong Jan 2023

Sedimentological Characteristics Of Storm Deposits Induced By The Tropical Storm Pa Buk Along The Western Coast Of The Gulf Of Thailand, Chanakan Ketthong

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tropical storm Pabuk (TS-Pabuk) attacked the western coast of the Gulf of Thailand (W-GOT) on January 4th, 2019, generating high storm surge levels, high wave height and leaving washover sediments along the coastal areas. Soon after the storm, an initial survey was set up for 44 localions to described sedimentary characteristics, measured beach topography, hydrodynamic intensities and geomorphological conditions. Then, the 4 main locations including Chao Samran beach (CSR), Ban Thung Noi (BTN), Thung Tako (TTK), and Talumphuk (TLP) were selected to study sedimentary detail, ground penetrating radar (GPR) with 3 frequencies and diatom analysis on their storm deposits. These …


Structural Geology And Deformation History In Klaeng Area, Rayong Province, Kittichai Chansom Jan 2023

Structural Geology And Deformation History In Klaeng Area, Rayong Province, Kittichai Chansom

Chulalongkorn University Theses and Dissertations (Chula ETD)

The geology of the Klaeng fault zone comprises of Ordovician metagranite, middle-late Paleozoic clastic sedimentary rocks, Triassic quartz-rich granites (west), Mesozoic redbed sandstones, Eocene granite (east), and mylonitic and low-to-medium-grade metamorphic rocks. In this study, four deformation events (D1-D4) are identified based on our new field observation and structural analysis in macroscale, mesoscale, and microscale. D1 (Late Triassic) characterizes tight folds in response to Triassic E-W Indosinian compression. D2 (Mesozoic) features gentle dips and open folds in redbeds due to E-W compression from regional transpression deformation. D3 (middle Eocene) exhibits a sinistral ductile shear in Eocene granite, which is dominated …


Structural Evolution Of The Phu Kradung Formation By Calcite Veins Characterization, South Of Lam Sonthi District, Lopburi Province., Ausa Nonthason Jan 2023

Structural Evolution Of The Phu Kradung Formation By Calcite Veins Characterization, South Of Lam Sonthi District, Lopburi Province., Ausa Nonthason

Chulalongkorn University Theses and Dissertations (Chula ETD)

Calcite veins in Mesozoic sedimentary rock localities are found in the southern part of Lam Sonthi district, Lopburi province, in central Thailand, near the Loei-Petchabun fold belt regions. The vein’s host rocks are siliciclastic rocks, primarily mudstone and sandstone. The main aim of this study is to learn more about calcite vein geometry and development, as well as the structural evolution of calcite veins in the Phu Kradung formation in the Lam Sonthi area of Lopburi province. A petrographic and structural analysis of the veins was performed to examine the kinematics and geological structures of the calcite vein in the …


Geophysical Characteristics Of Kuan Kreng Peat Swamp Forest At Thale Noi Area, Theethach Phiranram Jan 2023

Geophysical Characteristics Of Kuan Kreng Peat Swamp Forest At Thale Noi Area, Theethach Phiranram

Chulalongkorn University Theses and Dissertations (Chula ETD)

Peatlands, as an important carbon sink, store a large amount of atmospheric carbon. However, peatlands are vulnerable to environmental alteration due to anthropogenic and natural processes. While peatlands are degraded, carbon dioxide emissions arise. The Kuan Kreng peat swamp forest is the second largest peatland in Thailand and is in coastal wetland serving for carbon stock in the subsurface. To assess carbon stock in peatland, the thickness and distribution of the peat layer are necessary. This study determines physical and chemical characteristics of the peatlands in the coastal wetland, southern Thailand by conventional core study and geophysical surveys, including ground …


Investigating Elastic Deformation Induced By Surface Loads On Planetary Bodies, Ashlesha Khatiwada, Hilary Martens, Donald F. Argus Jan 2023

Investigating Elastic Deformation Induced By Surface Loads On Planetary Bodies, Ashlesha Khatiwada, Hilary Martens, Donald F. Argus

Graduate Student Theses, Dissertations, & Professional Papers

Planetary bodies, including the Earth, deform when there is a redistribution of surface load. In this thesis, I conduct three independent projects related to surface loading, two of which investigate methods related to the modeling of surface loading and one which seeks to catalog the displacement responses of other planetary bodies to a surface load.

The first project aims to compare four methods for modeling the elastic loading response of the Earth: a homogeneous, non-gravitating, half-space method; a homogeneous, gravitating, spherical method; a homogeneous, non-gravitating spherical method; and a radially stratified gravitating spherical method. Many studies have focused on computing …


Carbonates In The Critical Zone, M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, Á. A. García Jr., J. B. Heffernan, W. D. Graham Jan 2023

Carbonates In The Critical Zone, M. D. Covington, J. B. Martin, L. E. Toran, J. L. Macalady, N. Sekhon, P. L. Sullivan, Á. A. García Jr., J. B. Heffernan, W. D. Graham

Geosciences Faculty Publications and Presentations

Earth's Critical Zone (CZ), the near-surface layer where rock is weathered and landscapes co-evolve with life, is profoundly influenced by the type of underlying bedrock. Previous studies employing the CZ framework have focused primarily on landscapes dominated by silicate rocks. However, carbonate rocks crop out on approximately 15% of Earth's ice-free continental surface and provide important water resources and ecosystem services to ∼1.2 billion people. Unlike silicates, carbonate minerals weather congruently and have high solubilities and rapid dissolution kinetics, enabling the development of large, interconnected pore spaces and preferential flow paths that restructure the CZ. Here we review the state …


The Uncertain Future Of Landscapes Subjected To Mountaintop Removal Mining, Samuel James Bower Jan 2023

The Uncertain Future Of Landscapes Subjected To Mountaintop Removal Mining, Samuel James Bower

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increased erosion following human land disturbance is a global issue for ecosystem health and land management. Mountaintop removal (MTR) mining – a type of surface mining predominately found in the Central Appalachian Coalfields region – is one of the most significant examples of human perturbation to a natural landscape. A post-MTR landscape, when compared to its natural state, has significantly different erosive potential due to the rearrangement of topography from mining and reclamation practices. Removal of vegetation and alterations to soil further influence erosion by raising the effective erodibility of substrate subjected to MTR. We quantify the changes in erosion …


A Study Of Accidental Daughter Crystals In Fluid Inclusions In Bedded Halite From The Permian Opeche Shale And Cedar Hills Sandstone Of The Midcontinental United States, Ryan James Prchlik Jan 2023

A Study Of Accidental Daughter Crystals In Fluid Inclusions In Bedded Halite From The Permian Opeche Shale And Cedar Hills Sandstone Of The Midcontinental United States, Ryan James Prchlik

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ancient acid-saline lakes of the midcontinental United States deposited bedded halite during Permian time. These deposits are not typically preserved at the surface, but drill cores of the Opeche Shale of North Dakota and Cedar Hills Sandstone of Kansas contain preserved beds of halite. Halite from these ancient lakes have primary fluid inclusions that contain Permian lake water. Also included are accidental daughter crystals that were trapped inside the fluid inclusions at time of halite precipitation. Both the fluid and daughter crystals inside bedded halite can tell us about the geochemistry of original lake waters of Pangea.

Petrography and laser …


Bedrock Channel Geometry: Meter To Micron Scale Controls On Fluvial Incision, Nicholas J. Colaianne Jan 2023

Bedrock Channel Geometry: Meter To Micron Scale Controls On Fluvial Incision, Nicholas J. Colaianne

Graduate Theses, Dissertations, and Problem Reports (ETD)

The relative resistance of various rock types to incisional processes vary widely and the properties governing bedrock erodibility are poorly understood. Lithologic properties influencing erodibility are the culmination of a rock’s depositional, diagenetic, and exhumation processes. Difficulty identifying a convenient physical proxy for erodibility suggests examining evidence of these processes holistically may offer insight into the role of each in setting a rock’s resistance to incisional forces. In this study we use measured channel geometries along a short stretch of the Dry Fork, WV hosting three distinct lithologic settings to infer relative erodibility against measured and observed fluvial, lithologic, and …