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Textural And Mineral Analysis Of Pegmatites From The Pala And Mesa Grande Districts In San Diego, California, Gabrielle Potter 2023 The University of Akron

Textural And Mineral Analysis Of Pegmatites From The Pala And Mesa Grande Districts In San Diego, California, Gabrielle Potter

Williams Honors College, Honors Research Projects

San Diego pegmatites of the Pala and Mesa Grande mining districts are world renowned for their gem-quality minerals and their Li-bearing mineral phases. Pegmatite genesis, especially in San Diego mines, has been a debated topic since the 1900’s (Morgan and London, 2012). Pegmatite genesis is caused by partial melting processes and fractional crystallization that form granitic melts with high concentrations of rare earth elements (REE), such as lithium. Assessing the exact mineralogy and determining the overall textures can provide insight into the crystallization history of pegmatites. In the San Diego pegmatites, lithium-bearing phases, such as lepidolite and pink elbaite (a …


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

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 2023 Department of Primary Industries and Regional Development, Western Australia

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 2023 Department of Primary Industries and Regional Development, Western Australia

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 2023 University of Nebraska-Lincoln

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 2023 University of Nebraska at Lincoln

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 2023 University of Nebraska-Lincoln

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. 2023 University of Nebraska-Lincoln

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 2023 University of Nebraska - Lincoln

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 2023 University of Nebraska - Lincoln

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 2023 CUNY City College

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 2023 Missouri State University

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 2023 Missouri State University

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 2023 Missouri State University

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 2023 Northern Illinois University

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 2023 Northern Illinois University

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 …


Bibliography, Leslie North 2023 Western Kentucky University

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 2023 Missouri University of Science and Technology

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 2023 Georgia Southern University

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 2023 San Jose State University

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 …


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