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Machine Learning-Based Methods For The Segmentation Of Scanning Electron Microscopy Images Of Fine-Grained Shale Samples, Binqian Yin

Earth & Environmental Sciences Dissertations - Archive

The segmentation of scanning electron microscopy (SEM) images is critical yet time-consuming for geological studies, as it will need to differentiate the boundaries for different mineral objects to facilitate subsequent analyses, such as porosity calculation. Recently, machine learning methods, especially convolutional neural networks (CNNs), have been explored to segment SEM images for fine-grained shale samples. However, existing methods fail to address two critical issues in the segmentation of shale rock images---insufficient labeled data and imbalanced objects. To this end, this dissertation has proposed a machine learning pipeline that consists of supervised, semi-supervised, and active learning stages to reduce manual efforts …

Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert

United States Geological Survey: Staff Publications

The Miocene Climatic Optimum (MCO) provides important insights into how the climate system operates under elevated temperatures and atmospheric CO₂ levels. Few western North Atlantic paleotemperature or paleoecological records exist from the MCO, despite their importance for understanding both regional and global climate dynamics. Here we present quantitative MCO paleoecological data from the western North Atlantic, specifically from the Baltimore Gas & Electric (BG&E) marine sediment core from southern Maryland, USA. We examine alkenones and planktic foraminifera and document the first sea surface temperature (SST) and productivity estimates for the MCO and the Middle Miocene Climate Transition (MMCT) from …

Geomorphic And Paleoclimatic Implications Of Glacial Extent Records In The Sierra Nevada Del Cocuy, Colombia During Termination 1, Jordan Nickerson Herbert

Dartmouth College Master’s Theses

Reconstructions of past glacial extents using geomorphic mapping and cosmogenic dating provide an opportunity to infer past climates. A record of the past extents of tropical mountain glaciers is particularly useful because there are few other means to reconstruct past temperatures in high-altitude, low-latitude locations. The tropics play an outsized role in mediating global climate, yet there is a lack of understanding of how the tropics may have influenced past climate changes such as the most recent deglaciation (Termination 1, ~18–11.7 ka). Improving reconstructions of tropical mountain glaciers will aid in understanding the role of the tropics in the global …

Rock-Fluid Interaction And The Incorporation Of Cations Into Calcite During Recrystallization In Multiple Hydrothermal Systems., Van Anh Nguyen

Theses and Dissertations

Fluid-rock interaction causes an exchange of isotopes or elements through various reactions. The rate of these reactions strongly depends on temperature. The interaction involves dissolution precipitation, chemical exchange reactions, redox reactions, diffusion, and their combinations. The goal of studying fluid-rock interaction is to understand the change in mineral chemistry of the rock materials when in contact with an aqueous solution. These processes occur in all regions of the Earth where aqueous solutions are found. This work is comprised of three independent studies which provide an understanding about crystallization processes under multiple hydrothermal conditions with geological and environmental applications.

In the …

The Application Of Detrital Zircon Geochronology, Pressure-Temperature Modeling, Monazite Petrochronology, And Quartz-In-Garnet Elastic Geobarometry To The Tectonic Evolution Of The Funeral Mountains And Related Metamorphic Core Complexes, Suzanne Renae Mulligan

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation investigates and applies different techniques for studying mid-crustal metamorphic rocks including detrital zircon geochronology, monazite petrochronology, thermodynamic pressure-temperature modeling, and elastic geobarometry. The first chapter reconstructs stratigraphy in deformed metamorphic rocks from the Funeral Mountains metamorphic core complex in Death Valley, California, and the Bullfrog Hills, Nevada, using U-Pb detrital zircon (DZ) geochronology. This study documents another successful application of stratigraphic techniques applied to metamorphic rocks and migmatites. DZ geochronology identified Pahrump Group metasediments in rocks that were previously interpreted to be Paleoproterozoic basement gneisses, providing insights into the distribution of Rodinia rift basins. This analysis has shown …

Low-Temperature Plasticity Of Rock-Forming Minerals, Michael Keith Sly

Arts & Sciences Graduate Student Theses and Dissertations

The rheology of the Earth’s crust and mantle is in part governed by the physical and mechanical properties of feldspar, quartz, calcite, and olivine. Over the past several decades a significant number of experimental studies have been performed on these minerals. Conventional experiments are generally performed at elevated temperatures because much of the viscoplastic deformation of these minerals is accommodated by high-temperature mechanisms. There is, however, evidence of viscoplastic deformation at lower temperatures (T ≤ 0.3Tm) in the uppermost mantle and throughout the crust. Micromechanical experimental techniques, including nanoindentation and micropillar deformation, can be used to achieve plastic deformation at …

Systematic Integration Of Applications Into The Surface Biology And Geology (Sbg) Earth Mission Architecture Study, Christine M. Lee, Nancy F. Glenn, E. Natasha Stavros, Jeff Luvall, Karen Yuen, Stephanie Schollaert Uz

Geosciences Faculty Publications and Presentations

The Surface Biology and Geology (SBG) concept is the first National Aeronautics and Space Administration (NASA) Earth mission to develop and implement systematic integration of science application needs at the architecture study stage. Prior NASA mission concept and planning activities presumed that science measurement needs would encompasss application measurement needs and so did not explicitly evaluate and include applications at this stage. However, the effort presented here identified, documented and integrated application needs that would not have been included by considering research science needs only. First, a low latency of no greater than 24 hr was identified as the optimal …

Influencing Factors On Gas Production Effect Of Acid Fractured Cbm Wells In Deep Coal Seam Of Daning-Jixian Block, Li Shuguang, Wang Hongna, Xu Borui, Zhen Huaibin, Wang Chengwang, Yuan Pu

Coal Geology & Exploration

The No.8 deep coal seam in Daning-Jixian Block is large, thick, widely distributed, and rich in coalbed methane(CBM) resources. After volume acid fracturing, a breakthrough has been achieved in the producing test. However, the productivity of the testing wells varies greatly, and the major controlling factors of productivity are not clear, severely restricting the CBM development. In this paper, the testing wells in the No.8 coal seam with a buried depth of more than 2 000 m of the Upper Carboniferous Benxi Formation in Daning-Jixian Block were taken as the research object, and 28 typical evaluation indicators were selected from …

Segmentation Of The Wassuk Range Normal Fault System, Nevada (Usa): Implications For Earthquake Rupture And Walker Lane Dynamics, Benjamin E. Surpless, Sarah Thorne

Earth and Environmental Geosciences Faculty Research

Normal faults are commonly segmented along strike, with segments that localize strain and influence propagation of slip during earthquakes. Although geometry of segments can be constrained by fault mapping, it is challenging to determine seismically relevant segments along a fault zone. Because slip histories, geometries, and strength of linkages between normal fault segments fundamentally control the propagation of rupture during earthquakes, and differences in segment slip rates result in differential uplift of adjacent footwalls, we use along‐ strike changes in footwall morphology to detect fault segments and the relative strength of the mechanical links between them.

We apply a new …

Mineralogical, Petrological, And Geochemical Characteristics Of Şenkaya Chrysoprase,Turkey, Hami̇t Haluk Seli̇m, Aykut Güçteki̇n, Ferhan Şahi̇n, Mustafa Kaya, Beri̇l Kaya, Elanur Güner, Kami̇l Ömer Taş, Ahmet Karakaş, Yasemi̇n Kantarçeken

Turkish Journal of Earth Sciences

Şenkaya chrysoprase is a gemstone and can be found near the Turnalı village located in the west-northwest of Şenkaya (Erzurum) county in the uplifted Kırdağ of Northeast Anatolia of Turkey. Chrysoprase only found in Şenkaya County and known with the same name commercially in Turkey is a light-dark green and cryptocrystalline structure gemstone encountered in the Örükyayla Mélange. Samples were collected from the field for defining mineralogical-petrographical, XRD, XRF, ICP-MS, optical cathodoluminescence microscopy (OCLM), FTIR-Raman and stable isotopic properties of Şenkaya chrysoprase. According to mineralogical and petrographic examination, Şenkaya chrysoprase has generally heterogeneous color distribution in macroscale and has 5 …

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …

Investigating Depth Estimation To Archaeological Magnetic Source Bodies, Jeremy G. Menzer

Graduate Theses and Dissertations

Magnetometry is the most widely applied archaeo-geophysical technique. Current practice standards employ the technique to map only in a two-dimensional plan view fashion, but in deep geologic studies depth estimators are routinely applied to magnetic datasets. These estimators provide three-dimensional information to magnetic source-bodies. There are many different depth estimators employed in geologic study that all require various degrees of processing complexity. This study investigates two mathematically simple techniques, half-width rules and multi-height methods. Half-width rules are likely the oldest depth estimators within the field while multi-height techniques are but a minor footnote in the literature. The applicability of these …

Tectonomagmatic Evolution Of Northwestern Mexico, And Applications Of Machine Learning In Economic Geology, Jose Antonio Garcia

Open Access Theses & Dissertations

The work presented here was conducted in two study areas: La Preciosa mining project (Chapters 1 and 2) and Ray Mine (Chapter 3). Chapter 1 of this dissertation contributes to the tectonomagmatic evolution of northwestern Mexico by focusing on the temporal changes in magma source(s) regions, magma generation processes, and tectonic implications. In this chapter, I provide thin section analyses, whole rock geochemistry, in-situ zircon U-Pb ages and Hf isotope compositions of subsurface lithologies from La Preciosa mining project; located in the northwestern corner of Mesa Central, Durango, Mexico. The newly acquired data identified five magmatic events. The first consists …

Measurement Of Radon Gas At Kilbourne Hole, Michel Eduardo Luna Lucero

Open Access Theses & Dissertations

Several radon studies have reported a possible correlation of the gas emanation with faults and seismic activity in the area, but few studies have been conducted in seismically inactive areas. Features such as the Kilbourne Hole in New Mexico, a maar volcano formed by an interaction between magma and water, can reveal important information about connection between radon concentration levels and structural geology.

The purpose of this thesis is to determine the radon concentration levels in and around the crater of the Kilbourne Hole. The results are compared with geological, gravity and magnetic surveys to have a better understanding of …

Resolution Of Lava Tubes With Ground Penetrating Radar, Sanaz Esmaeili

USF Tampa Graduate Theses and Dissertations

Finding habitable places to keep astronauts safe from surface radiation, magnetic storms, and temperature fluctuations will be an important component of future planetary exploration missions. Remote sensing surveys on other planets indicate the presence of lava tubes. Ground Penetrating Radar (GPR) has shown great potential for detection of tunnels in terrestrial environments. In this research, the capabilities of this near surface rapid exploratory tool for detection of lava tubes are investigated. This dissertation describes terrestrial examples of how GPR can be utilized to explore tubes and addresses the capabilities of GPR for resolving tube-related features such as the floor, fractures, …

Initial Acoustoelastic Measurements In Olivine: Investigating The Effect Of Stress On P- And S-Wave Velocities, Taryn K. Traylor, Pamela C. Burnley, M. L. Whitaker

Geoscience Faculty Research

It is well known that elasticity is a key physical property in the determination of the structure and composition of the Earth and provides critical information for the interpretation of seismic data. This study investigates the stress-induced variation in elastic wave velocities, known as the acoustoelastic effect, in San Carlos olivine. A recently developed experimental ultrasonic acoustic system, the Directly Integrated Acoustic System Combined with Pressure Experiments (DIASCoPE), was used with the D-DIA multi-anvil apparatus to transmit ultrasonic sound waves and collect the reflections. We use the DIASCoPE to obtain longitudinal (P) and shear (S) elastic wave velocities from San …

Findings Report: Virtual Workshop On ‘Resilient Supply Of Critical Minerals’, Marek Locmelis, Angela D. Lueking, Michael S. Moats, Kwame Awuah-Offei, Lana Z. Alagha, Mark W. Fitch, Alanna Krolikowski, Shelby Clark

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Executive Summary
On August 2-3, 2021, the Thomas J. O’Keefe Institute for Sustainable Supply of Strategic Minerals at Missouri University of Science and Technology (Missouri S&T) hosted the NSF-funded virtual workshop ‘Resilient Supply of Critical Minerals’. The workshop was convened via Zoom and attracted 158 registrants, including 108 registrants from academia (61 students), 30 registrants from government agencies, and 20 registrants from the private sector. Four topical sessions were covered:

A. Mineral Exploration and Source Diversification.
B. Supply Chain and Policy Issues.
C. Improving Mineral Recycling and Reprocessing Technologies.
D. Technological Alternatives to Critical Minerals.

Each topical session was composed …

Exploring Questions Of Tectonic Geomorphology In The Bear River Range, Utah Using Terrain Analysis And Reconstruction, Edward M. Grasinger

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Despite a long tradition of geologic studies in the region surrounding Utah State University, there remain unexplored questions and unutilized approaches for understanding the landscape evolution of the Bear River Range. A large-scale reconstruction of the East Cache fault system can be useful in estimating the total displacement of the fault, its geologic longevity, and total energy involved. Likewise, an analysis of reach-scale features of the Logan River can explore how tectonics and bedrock type affect the patterns and history of the river. Geographic Information Systems (GIS) software is useful in reconstructing, visualizing, and measuring such geomorphological features and changes …

Simulating Cambrian Climate: The Significance Of Atmospheric Co2 Concentration And Continental Position, Grace Cutting

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The Cambrian Period began approximately 541 million years ago, and is known for the “Cambrian Explosion”, a time when multicellular life began to rapidly diversify. There is natural historic evidence (isotopes, rock formations, and fossils) that suggests the Cambrian Period experienced a warm climate. However, there is also conflicting evidence that the Cambrian climate may have undergone freezing and thawing cycles, with ice possibly present near the equator. It is critical to understand how ecosystems were able to adapt to past climate changes, especially when analyzing the impacts of modern human activity on climate. Climate model simulations were run to …

Geologic Study Of The Palisades Park, Spokane, Washington, Ethan Jeffrey Ducken, Alex Michael Navarra

Geosciences Student Work

The Palisades Park is a large City owned tract of land located on the western bluffs above Spokane. The purpose of this project was to create a geologic map and assess the features within the park for the benefit of a public conservation group, Friends of the Palisades. There are 3 main units identified by previous research in the vicinity. Volcanic rock units are part of the Columbia River Basalt Group (CRBG), which erupted primarily between 16.5 to 15.6 MA (Hammond 2013). Large sedimentary interbeds identified as Latah formation present between CRB flows (Swanson et al 1979a, 1979b). Latah formation …

Mapping Of Geological Structural Features In Lolgorien, Narok County, Kenya: Using Hillshade Analysis, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi

Tanzania Journal of Science

Despite Lolgorien being one of the most active gold mining areas in Kenya, it is one of the most geologically understudied areas. To the best knowledge of the authors, Lolgorien geological map was last updated in the 1940s. Current technologies such as remote sensing allow new structural features such as faults to be easily identified. In this regard, this study employed remote sensed data to map structural features found in and around Lolgorien Subcounty, Narok, Kenya. This was done to identify any new structural features that might have been missed in the past. Shuttle Radar 152 Topography Mission Digital Elevation …

Integration Of Geophysics And Remote Sensing Techniques In Mapping Zones Mineralised With Disseminated Gold And Sulphide Minerals In Lolgorien, Narok County, Kenya, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi

Tanzania Journal of Science

Even though ground geophysical surveys (especially Induced polarization and resistivity) are applied in mineral exploration, their effectiveness in identification of mineralised zones is often enhanced by integrating other mineral exploration techniques such as remote sensing and geological investigations. Integrating different techniques helps in reducing uncertainty that is often associated with mineral exploration. The methods being integrated also depend on characteristics of mineralisation and those of host rock. In this study, geophysical survey methods (induced polarization and resistivity) were integrated with remote sensing and geological methods to delineate mineralised zones in Lolgorien beyond reasonable doubt. By integrating these methods, it was …

Spatial And Temporal Patterns Of River Incision And Terrace Deposition In Response To Climate And Tectonics In Southern Taiwan, Dominique M. Shore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geologists often look at the Earth’s surface to understand the underlying processes that cause mountain formation. As tectonic forces drive uplift of Earth’s surface, processes of erosion transport sediment to lower elevations. Climate can play a large role in landscape formation as well as increased precipitation, accelerating rates of erosion. Rivers leave markers of landscape evolution through terrace landforms, former river floodplains that are left behind when rivers incise into a valley. To better understand landscape response to uplift, this research investigated the initial linkages between uplift, hillslope erosion (mass wasting) and river incision. At some point, it is thought …

Discussion On Roof Water Loss Control Method Of Coal Seam Based On Pre-Splitting Grouting Reformation(P-G), Zhao Chunhu, Wang Hao, Jin Dewu

Coal Geology & Exploration

In view of the technical requirements of roof water disaster prevention and water resources collaborative protection faced by coal mining in western coal mining area, this paper puts forward a technical idea of roof water loss control based on pre-splitting grouting reformation(P-G) according to the strain strength theory of material mechanics and the statistical results of mining fracture zones of different overburden types. The basic principle is that the continuous bedrock layer will be fractured into discontinuous rock layers by fracturing technology, and by weakening the “tip effect” of upward expansion of mining induced water flowing fracture in hard rock …

Validating Geoclaw For Simulating Teton Dam Failure By Comparison With Hec-Ras Results And Historical Observations, Hannah R. Spero

Geosciences Undergraduate Theses

The combination of dams degrading with age and other factors like climate change, technical errors, and human errors lead to dams breaching and failing worldwide. In the United States, over 40,000 dams pose a threat to downstream inhabited areas and constitute a widespread hazard if they were to breach. Therefore, it is critical to accurately predict the resultant floods’ downstream flow behavior to create a more resilient community. By improving research, we can concurrently develop and improve mitigation strategies for downstream communities. This study benchmarks the GeoClaw numerical modeling software with the well-documented 1976 Teton Dam failure. A vital tool …

Characterization Of Uranium, Lead, And Rare Earth Element Pollution In Natural Soils And Sediments, Hope Rasmussen

Civil and Environmental Engineering Theses and Dissertations

Heavy metals in the environment add to the global burden of pollution, negatively impacting public health and ecosystem resilience. This study included projects regarding uranium (U), lead (Pb), and rare earth elements (REE) in natural samples, due to their known toxicity, ubiquity, and relevance in context to recent pollution trends. The first project focused on testing the potential of using a hydroxyapatite product as a remediation solution for U-contaminated groundwater and soil at an EPA Superfund site. The results showed that the U was sequestered in a highly crystalline mineral form within the solids, guiding the EPA to specify the …

Geology Study – Drilling Down At Red Trail Energy, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about a 2019–2020 geophysical survey near Richardton, North Dakota. The survey investigated the area’s feasibility as a CO₂ storage site, as part of the Red Trail Energy carbon capture and storage (CCS) research effort. Summarizes survey process and results. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Geology And Fossils Of North Central Texas (Fort Worth To Mineral Wells): Texas Academy Of Science February 28 2021, R. Larell Nielson

Faculty Publications

The 2021 Texas Academy of Science Geology field trip will be a virtual field trip that you may run at any time. It will have two parts;Part 1 consists of a video discussion of each stop( https://www.youtube.com/watch?v=EJKSgqtLvw0)and Part 2 consists of this field trip guidebook (for use when visiting each of the locations). The field trip will start at Holiday Park,near Benbrook,southwest of Fort Worth,Texas, and will end at the Mineral Wells Fossil Park, west of Minerals Wells, Texas. T

Age And Paleoenvironmental Significance Of The Frazer Beach Member: A New Lithostratigraphic Unit Overlying The End-Permian Extinction Horizon In The Sydney Basin, Australia, James L. Crowley

Geosciences Faculty Publications and Presentations

The newly defined Frazer Beach Member of the Moon Island Beach Formation is identified widely across the Sydney Basin in both outcrop and exploration wells. This thin unit was deposited immediately after extinction of the Glossopteris flora (defining the terrestrial end-Permian extinction event). The unit rests conformably on the uppermost Permian coal seam in most places. A distinctive granule-microbreccia bed is locally represented at the base of the member. The unit otherwise consists of dark gray to black siltstone, shale, mudstone and, locally, thin lenses of fine-grained sandstone and tuff. The member represents the topmost unit of the Newcastle Coal …

Toward An Integrative Geological And Geophysical View Of Cascadia Subduction Zone Earthquakes, Maureen A.L. Walton, Lydia M. Staisch, Tina Dura, Jessie K. Pearl, Brian Sherrod, Joan Gomberg, Simon Engelhart, Ray E. Wells, Multiple Additional Authors

Geology Faculty Publications and Presentations

The Cascadia subduction zone (CSZ) is an exceptional geologic environment for recording evidence of land-level changes, tsunamis, and ground motion that reveals at least 19 great megathrust earthquakes over the past 10 kyr. Such earthquakes are among the most impactful natural hazards on Earth, transcend national boundaries, and can have global impact.Reducing the societal impacts of future events in the US Pacific Northwest and coastal British Columbia, Canada, requires improved scientific understanding of megathrust earthquake rupture, recurrence, and corresponding hazards. Despite substantial knowledge gained from decades of research, large uncertainties remain about the characteristics and frequencies of past CSZ earthquakes. …