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Articles 9541 - 9570 of 59520

Full-Text Articles in Earth Sciences

Enhancing Basic Geology Skills With Artificial Intelligence: An Exploration Of Automated Reasoning In Field Geology, Perry Ivan Quinto Houser May 2023

Enhancing Basic Geology Skills With Artificial Intelligence: An Exploration Of Automated Reasoning In Field Geology, Perry Ivan Quinto Houser

Open Access Theses & Dissertations

This thesis explores the use of Artificial Intelligence, specifically semantics, ontologies, and reasoner techniques, to improve field geology mapping. The thesis focuses on two use cases: 1) identifying a geologic formation based on observed characteristics; and 2) predicting the geologic formation that might be expected next based upon known stratigraphic sequence. The results show that the ontology was able to correctly identify the geologic formation for the majority of rock descriptions, with higher search results for descriptions that provided more detail. Similarly, the units expected next were correctly given and if incorrect, would provide a flag to the field geologist …

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Enhancing Earthquake Detection Through Machine Learning- An Application To The 2017 Mw 8.2 Tehuantepec Earthquake In Mexico, Marc Adrian Garcia May 2023

Enhancing Earthquake Detection Through Machine Learning- An Application To The 2017 Mw 8.2 Tehuantepec Earthquake In Mexico, Marc Adrian Garcia

Open Access Theses & Dissertations

The Tehuantepec seismic gap, located off the southern shore of Oaxaca and Chiapas, Mexico, was previously thought to be an aseismic zone due to no significant event in 100 years. The September 8, 2017 (M8.2) Tehuantepec earthquake disproved this idea and added many questions surrounding the Mexican subduction zone. Specifically, the earthquake did not occur at the subduction megathrust. It ruptured the subducting plate below the megathrust and appeared to stop at the megathrust. Following this event, as well as the September 19, 2017 (M7.1) Morelos-Puebla earthquake, researchers from the University of Texas at El Paso (UTEP), Universidad Autónoma Cuidad …

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Performance Classification Of Ornstein-Uhlenbeck-Type Models Using Fractal Analysis Of Time Series Data., Peter Kwadwo Asante May 2023

Performance Classification Of Ornstein-Uhlenbeck-Type Models Using Fractal Analysis Of Time Series Data., Peter Kwadwo Asante

Open Access Theses & Dissertations

This dissertation aims to assess the performance of Ornstein-Uhlenbeck-type models by examining the fractal characteristics of time series data from various sources, including finance, volcanic and earthquake events, US COVID-19 reported cases and deaths, and two simulated time series with differing properties. The time series data is categorized as either a Gaussian or a Lévy process (Lévy walk or Lévy flight) by using three scaling methods: Rescaled range analysis, Detrended fluctuation analysis, and Diffusion entropy analysis. The outcomes of this analysis indicate that the financial indices are classified as Lévy walks, while the volcanic, earthquake, and COVID-19 data are classified …

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Explaining Spatio-Temporal Evolution Of Extreme Hydro-Climatic Events Using A Complex Network Framework, Somnath Mondal May 2023

Explaining Spatio-Temporal Evolution Of Extreme Hydro-Climatic Events Using A Complex Network Framework, Somnath Mondal

All Dissertations

Severe hydroclimatic extreme events, such as droughts, heatwaves, and heavy rainfall, are occurring with increasing frequency and causing significant impacts on both people and the environment. These events also compound in space and time, leading to even more significant consequences. Therefore, it is essential to comprehend these phenomena' concurrent and time-delayed progression across different temporal and spatial scales to address adaptation and mitigation effectively. To accurately understand and map the co-evolution of extreme events, it's necessary to have a thorough grasp of their spatiotemporal patterns, how they propagate and interact with one another, and the underlying mechanisms driving their occurrence. …

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Characterization Of Hematite Coated Bedrock Fault Scarps In The Northern Colorado River Extensional Corridor Near Lake Mead, Nevada, Molly E. Pickerel May 2023

Characterization Of Hematite Coated Bedrock Fault Scarps In The Northern Colorado River Extensional Corridor Near Lake Mead, Nevada, Molly E. Pickerel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fault mirrors are reflective, thin, typically <1 mm thick, fault slip surfaces in exhumed fault zones that can provide a record of thermal, chemical, and rheological changes to fault materials during deformation. This study investigates a series of hematite coated fault mirrors along bedrock fault scarps in Miocene volcanic rocks near Lake Mead, Nevada. The studied faults are located in a structurally complex area that includes NE-SW trending left-lateral strike-slip faults of the Lake Mead fault system, NW-SE right-lateral strike-slip faults of the Las Vegas Shear Zone, and N-S striking extensional faults of the Northern Colorado River Extensional Corridor.New zircon U-Pb ages from fault scarp host rocks 21-BC-03 and 21-BC-05 are and 13.86 ± 0.27 Ma and 12.90 ± 0.31 Ma (2σ standard error), respectively. New apatite (U-Th)/He dates range from 5.64 ± 0.46 Ma to 12.4 ± 0.36 Ma (2σ standard error) and are interpreted to be partially reset after eruption due to reheating. Inverse thermal history modeling in HeFTy of apatite He dates indicates a thermal history of reheating to ~65 °C which is interpreted as shallow burial around ~11 - 5 Ma followed by cooling to the surface, interpreted as exhumation between ~4.5 - 2 Ma. The zircon U-Pb ages, apatite He dates, and inverse thermal history models indicate the fault host rocks were erupted to the surface and stayed within the upper ~2 km of the crust since the Miocene. Nearly vertical fault scarps that host the fault mirror surfaces exhibit two sets of slickenlines, indicating oblique and strike-slip motion, with different orientations indicating that there have been multiple episodes of deformation along the surfaces. Three of the five studied fault scarps have E-W orientations, and one scarp is NW-SE, and one is NE-SW striking. The studied faults are interpreted to have been active during deformation associated with the Lake Mead Fault System and the Las Vegas Valley Shear Zone at 13 – 9 Ma and record both strike slip and oblique slip events in the complex strain field during this time. Micro-nano scale texture and grain morphology analysis of the hematite fault mirror volumes shows extreme strain localization along the fault mirror surface. Some fault mirrors exhibit multiple domains separated by discrete slip surfaces. Comminution and cataclasis appear to be the dominant deformation mechanisms in the fault mirror volume. Hematite textures and morphologies are consistent with observations from other fault systems that are interpreted to record aseismic to sub-seismic slip rates, and relatively low coseismic temperature rise. Fluid injection veins and post-deformation FeO mineralization in fractures are interpreted as evidence of high fluid pressures during slip and fluid circulation postdeformation. The new geochronologic and microstructural data inform on the processes operating along discrete fault surfaces in the shallow crust since the Miocene in the Lake Mead region.

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Morphologic Comparisons Of Recrystallized And Neocrystallized Fibrous Amphibole Asbestos: Implications For Corresponding Health Risk Potential, Natalie G. Renkes May 2023

Morphologic Comparisons Of Recrystallized And Neocrystallized Fibrous Amphibole Asbestos: Implications For Corresponding Health Risk Potential, Natalie G. Renkes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The presence of naturally-occurring asbestos (NOA) is increasingly concerning for scientists, health and regulatory agencies, and citizens living in impacted areas. It is commonly believed that fibrous amphibole asbestos can only form through neocrystallization. In southern Nevada, NOA occurs as a result of hydrothermal alteration of granitic rock producing fibrous amphibole both as cross-cutting neocrystallized veins and via recrystallization of original magmatic hornblende crystals. Fibers with a greater aspect ratio are known to have increased toxicity. This study measured the maximum length and average width of both neocrystallized and recrystallized fibers to see if the morphologies were similar. Neocrystallized and …

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Evaluation Of Zero-Net-Rate Pumping Tests, Austin Smith-Jones May 2023

Evaluation Of Zero-Net-Rate Pumping Tests, Austin Smith-Jones

All Theses

Accurately estimating the distribution of aquifer properties is key to understanding contaminant movement in the subsurface. The distribution of aquifer properties is typically addressed using slug or constant-rate well tests, and the pros and cons of these tests are well known. Slug tests are appealing because they avoid removing contaminated water, but their results are affected by well skin and the small volume of displaced water limits the volume of aquifer that can be evaluated. Constant-rate well tests have the disadvantage of requiring disposal of potentially contaminated water, but they can generate properties that are more representative than slug tests, …

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Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris May 2023

Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris

All Theses

Since the 1950s, the United States has produced approximately 90,000 metric tons of spent nuclear fuel (SNF) (Office of Nuclear Energy, 2022); however, no long-term storage solutions are available. Technecium-99 and neptunium-237, two fission products found in SNF, readily form highly mobile species in oxidizing conditions (Hu, 2008; Bondietti, 1979) and have respective half-lives of 2.13 x 105 and 2.14 x106 years (Hu, 2010). Considering these characteristics, 99Tc and 237Np are two risk-driving isotopes found in SNF storage. The process of macropore-facilitated preferential flow, transport through cracks within a soil matrix, has been recognized to increase …

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Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping May 2023

Quantifying Heterogeneity Along A Hillslope Using Seismic Refraction, Structure From Motion, And X-Ray Fluorescence In The Piedmont, South Carolina, Leah Topping

All Theses

The critical zone (CZ) is the life sustaining outer layer of the earth that spans from the top of unweathered bedrock to the tops of the trees. This dynamic zone is always evolving because a variety of chemical, physical, and biological processes transform bedrock into regolith, creating a spatially heterogeneous CZ architecture. This study aims to investigate the relationships between regolith thickness, seismic velocities, and chemical profiles as a function of slope position and it is hypothesized bedrock composition, fracture density, and foliation are the key factors controlling the physical heterogeneity in the top 1-2 meters of the CZ. To …

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Net-Zero Target And Emissions From Land Conversions: A Case Study Of Maryland's Climate Solutions Now Act, Philip Hutton May 2023

Net-Zero Target And Emissions From Land Conversions: A Case Study Of Maryland's Climate Solutions Now Act, Philip Hutton

All Theses

Many climate change “solution” plans include net-zero goals, which involve balancing the anthropogenic greenhouse gas emissions (GHG) with their removal. Achieving net-zero goals is particularly problematic for soils because they are often excluded from GHG inventories and reduction plans. For example, Maryland’s Climate Solutions Now Act (Senate Bill 528) put forward a target of net-zero emissions by 2045. To achieve these goals, the state of Maryland (MD) needs to quantify GHG emissions. Soils are currently excluded from MD’s GHG assessments. This study examines the challenges in meeting net-zero goals by using carbon dioxide (CO2). The current study quantified …

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Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee May 2023

Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Comprehending the natural water resource is imperative for the entire state of Nevada and of particular significance for Southern Nevada, where rapid population growth and climate change are placing significant strain on supplies. This research underscores the significance of water chemistry in identifying potential water source areas through trace elements. For the first time, the study proposed measuring the compositions of the entire suite of metal elements, ranging from Li to U, in over 40 springs in the Moapa Valley and its upper gradient valleys, utilizing the iCAP Qc ICP-MS (Inductively Coupled Plasma Mass Spectrometer) at UNLV. The research evaluated …

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Critical Metals: From Granitic Pegmatites To The Anthropogenic Cycle, Dalton Mccaffrey May 2023

Critical Metals: From Granitic Pegmatites To The Anthropogenic Cycle, Dalton Mccaffrey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Critical metals are vital to the functionality of the modern world. The increased diversity and usage intensity of these commodities in defense-related and strategic technologies (e.g., jet engines, rocket assemblies), modern infrastructure and products (e.g., high-strength steel, cellular phones, laptop computers), and energy-related, low-emissions technologies (e.g., nuclear reactors, solar panels, wind turbines, hybrid and electric vehicles) has drastically increased our reliance on critical metals and, thus, the United States (and global) exposure to supply restrictions. Granitic pegmatites are unique mineral deposits that represent a past, present and future resource for many (approximately half) of these critical resources. Even with the …

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Modeling The Impacts Of Sea Level Rise In Coastal Virginia At Multiple Scales, George Murray Mcleod Iv May 2023

Modeling The Impacts Of Sea Level Rise In Coastal Virginia At Multiple Scales, George Murray Mcleod Iv

OES Theses and Dissertations

Relative sea level is increasing along the Mid-Atlantic coast of the United States and the rate of relative sea level rise (ΔRSL) for Coastal Virginia is approximately double the rate of global sea level rise (ΔSLRG)(1). The potential impacts posed to communities by ΔRSL are best understood by examining the spatial relationship between the upper limits of ocean-connected waters and the geographic positioning of critical natural and societal assets. This research examines this problem at three spatial scales to quantify the impacts of ΔRSL and storm flooding events on (i) structural and transportation infrastructure for the tide-influenced coastal zone of …

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Assessment Of Phytoplankton Assemblages And Harmful Algal Blooms In New Jersey, Yaritza Acosta Caraballo May 2023

Assessment Of Phytoplankton Assemblages And Harmful Algal Blooms In New Jersey, Yaritza Acosta Caraballo

Theses, Dissertations and Culminating Projects

Urbanization, industrialization, and climate change have played a major role in the pollution of waterways, leading to a global increasing trend of harmful algal blooms (HAB) while jeopardizing water quality. Phytoplankton and HAB were evaluated within the highly urbanized and historically polluted state of New Jersey to help provide statewide baseline data for HAB and water quality management. A total of three studies were included in this dissertation. In the first study, phytoplankton communities were characterized in freshwaters of New Jersey during the cyanobacterial HAB season and their relationships to water quality at both statewide and ecoregion levels were examined. …

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Seasonal Variations In Nutrient And Total Suspended Solids Sources And Fluxes In Rivers Of Northern New Jersey And Newark Bay, Usa, Jing Nie May 2023

Seasonal Variations In Nutrient And Total Suspended Solids Sources And Fluxes In Rivers Of Northern New Jersey And Newark Bay, Usa, Jing Nie

Theses, Dissertations and Culminating Projects

In recent decades, aquatic systems have experienced major problems with water quality due to high nutrient concentrations from both point and non-point sources resulting from industrialization, urbanization, and population growth. While nutrient pollution due to land use change cannot be ignored, point sources such as combined sewer overflows and discharging sites have also contributed to the problem. Integrated hydrodynamic, chemical, and biological models have been developed to simulate nutrient transportation from both sources. This paper reviews and analyzes water quality data from published literature to evaluate nutrient pollution in aquatic systems and emphasizes the need for a continuously developed integrated …

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Antarctic Peninsula Ice Sheet Dynamics In The Pliocene From Sedimentological Interpretation Of Ocean Drilling Program Site 1097, Ridley Joseph May 2023

Antarctic Peninsula Ice Sheet Dynamics In The Pliocene From Sedimentological Interpretation Of Ocean Drilling Program Site 1097, Ridley Joseph

Theses, Dissertations and Culminating Projects

Studying ice sheet behavior during the Pliocene Epoch is of great importance. The Early Pliocene was characterized by warm climatic conditions, similar carbon dioxide levels and high sea levels compared to the present. This time frame provides essential information on the foreseeable future of Earth’s cryosphere, particularly if climate change continues to persist. The sedimentary record of the Antarctic Peninsula Ice Sheet (APIS) is the focus of this study. At Ocean Drilling Program (ODP) Site 1097, cores were drilled into Pliocene strata at a shallow depth on the Antarctic Peninsula continental shelf. Sedimentary facies were interpreted, and twenty samples were …

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Potential Of Increased Thermal Tolerance As A Response To Acute Heat Stress In A Disease-Transmitting Mosquito Species, Nicole Ashley Scanlon May 2023

Potential Of Increased Thermal Tolerance As A Response To Acute Heat Stress In A Disease-Transmitting Mosquito Species, Nicole Ashley Scanlon

Theses, Dissertations and Culminating Projects

Each year hundreds of millions of people are infected with mosquito-borne illnesses. West Nile Virus is the leading cause of mosquito-borne diseases in the United States (McDonald et al., 2021). The first case of West Nile Virus was detected in the United States in 1999 (Sejvar, 2003). Since that time the number of cases has dramatically risen. Mosquitoes are ectotherms which means their body temperature is dependent on the thermal conditions outside of their body. Because of this they are very sensitive to changes in their environment. The Earth’s average temperature has been slowly but steadily rising. This small but …

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An Age, Size, And Climate Response Study Of Old Growth Shortleaf Pine In The Mccurtain County Wilderness Area, Oklahoma, Nicholas Cancalosi-Dean May 2023

An Age, Size, And Climate Response Study Of Old Growth Shortleaf Pine In The Mccurtain County Wilderness Area, Oklahoma, Nicholas Cancalosi-Dean

Graduate Theses and Dissertations

Increment cores were extracted from 483 trees distributed over 21 semi-randomly sampled 0.1-hectare plots on three distinct landscape positions in the McCurtain County Wilderness Area (MCWA), a 57 square kilometer tract of uncut shortleaf pine in southeastern Oklahoma. Forty additional cores were taken off plot from older-appearing trees. All sampled trees were shortleaf pine (Pinus echinata) with a diameter at breast height (DBH) of at least 10 cm. Hardwoods were not included in the size and age analyses. The study site chosen for the sampling was made up of four parallel east-west trending ridges near North Linson Creek, making up …

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The Terroir Of Swiss Cheese: A Temporal And Geomorphological Investigation Of The Martian Co2 Sublimation Pits, Racine D. Cleveland May 2023

The Terroir Of Swiss Cheese: A Temporal And Geomorphological Investigation Of The Martian Co2 Sublimation Pits, Racine D. Cleveland

Graduate Theses and Dissertations

Observations by NASA Mars Global Surveyor showed evidence of rough topography on the South Pole of Mars. The topography is the result of CO2 sublimation processes that occur through the changing seasons on the red planet. These sublimation areas are known to scientists as Swiss Cheese Features (SCF). SCF are erosional degradation pits that have been studied for over two decades. Studies show that these SCF increase in area over time, but these values are collected by hand on a per feature basis. Models for the pit evolution have also played a part in understanding these SCF. This work is …

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Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud May 2023

Identifying Taphonomic Distribution Patterns At The Gray Fossil Site, Shawn Haugrud

Electronic Theses and Dissertations

Since the early days of the discovery of the Gray Fossil Site (GFS), meticulous efforts to preserve the spatial data were a priority. Direct surveying of fossils prior to recovery, as well as grid mapping the site, provided relative spatial data within a square meter. Such efforts meant that even fragments and microfossils, recovered during the screening operations and eventual concentrate picking, maintained some spatial data. Available spatial data are used to identify smaller deposits within the greater system, as well as non-random distribution patterns among a number of GFS taxa. Patterns are particularly pronounced in the large-bodied taxa, Teleoceras …

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First Skulls Of Arctomeles Dimolodontus (Mustelidae: Melinae) From The Gray Fossil Site (Early Pliocene, Tn) Reveal Extreme Intraspecific Variation, Charles Bruce May 2023

First Skulls Of Arctomeles Dimolodontus (Mustelidae: Melinae) From The Gray Fossil Site (Early Pliocene, Tn) Reveal Extreme Intraspecific Variation, Charles Bruce

Electronic Theses and Dissertations

Here, a morphological description of the extinct meline badger Arctomeles dimolodontus from the Gray Fossil Site (GFS), Tennessee is provided with comparison to extant Meles meles. Originally described solely on upper teeth of a single individual, the recovery of several crania and jaws provides a sample of at least five individuals, affording the largest known fossil sample in North America of the enigmatic Melinae. Examination of A. dimolodontus skull material reveals extreme intraspecific variation in previously identified diagnostic characters, highlighting the need for caution when identifying fossil taxa based on similarly fragmentary remains. Dental variation is likely a result …

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Assessing A Pandemic: Spatiotemporal Analysis Of Covid-19 In Tennessee School-Age Children, Omobolaji Olawuyi May 2023

Assessing A Pandemic: Spatiotemporal Analysis Of Covid-19 In Tennessee School-Age Children, Omobolaji Olawuyi

Electronic Theses and Dissertations

This study is a spatiotemporal analysis of the COVID-19 pandemic in school-age children (5-18 years) in Tennessee, from 2020-03-19 to 2022-02-12. Trend Analysis, Emerging Hot Spot Analysis, and a time series revealed three significant waves in both age groups. Therefore, Change Point Detection at the county level was completed using six defined change points to identify the wax and wane of the three COVID-19 waves. Hierarchical Cluster Analysis grouped counties with similar change points into six clusters. No spatial pattern was observed in distribution of the six clusters, however, when each change point was evaluated separately, spatial autocorrelation was present, …

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Hydrodynamic Characteristics And Sediment Distribution Patterns In Wulan Delta Estuary, Demak, Indonesia, Max Rudolf Muskananfola, Sigit Febrianto, Diah Ayuningrum Apr 2023

Hydrodynamic Characteristics And Sediment Distribution Patterns In Wulan Delta Estuary, Demak, Indonesia, Max Rudolf Muskananfola, Sigit Febrianto, Diah Ayuningrum

Makara Journal of Technology

The Wulan Delta, located in Wedung, Demak, was formed due to the sedimentation process of the Wulan and Serang rivers. Sediment transport starts from rivers to the sea; the process carries nutrients and various chemicals derived from agricultural, industrial, or household activities. This study aims to analyze the characteristics of hydrodynamics, suspended sediment, and bottom sediments in the Wulan Delta waters, Demak. Field data were collected in transitional season two (October) 2022. The obtained data were then analyzed in the laboratory at the Faculty of Fisheries and Marine Science. Results showed that the speed of the surface current in the …

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Numerical Simulation On Development Effect Of Tar-Rich Coal Through In-Situ Conversion By Convective Heating In Huangling Mining Area, Dong Guangshun, Zhu Chaofan, Li Jiazong, Xu Shaotao, Guo Wei Apr 2023

Numerical Simulation On Development Effect Of Tar-Rich Coal Through In-Situ Conversion By Convective Heating In Huangling Mining Area, Dong Guangshun, Zhu Chaofan, Li Jiazong, Xu Shaotao, Guo Wei

Coal Geology & Exploration

The effective development of tar-rich coal to extract oil is of great practical significance to alleviate the oil and gas tension in China, and the convective heating technology of underground in-situ mining is one of the main technologies for the effective development of tar-rich coal. Herein, the mining effect and energy return rate of the two heating media (high-temperature steam and nitrogen) under different injection pressures were studied by convective heating technology for underground in-situ conversion mining based on the tar-rich coal seam of Yan'an Formation in Huangling Mining Area. The results show that: the heating efficiency of steam injection …

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Mechanical Property Evaluation Of Coal Bed And Favorable Area Prediction Of Coalbed Methane (Cbm) Development Based On Well Logging: A Case Study Of No. 3 Coal Bed In Zhengzhuang Block, Southern Qinshui Basin, Qiu Feng, Liu Jinhua, Cai Yidong, Liu Dameng, Sun Fengrui Apr 2023

Mechanical Property Evaluation Of Coal Bed And Favorable Area Prediction Of Coalbed Methane (Cbm) Development Based On Well Logging: A Case Study Of No. 3 Coal Bed In Zhengzhuang Block, Southern Qinshui Basin, Qiu Feng, Liu Jinhua, Cai Yidong, Liu Dameng, Sun Fengrui

Coal Geology & Exploration

Accurately grasping the mechanical properties of coal is of great significance to reservoir reconstruction and CBM development. Herein, the prediction model of shear wave time difference in coal reservoir based on multiple logging parameters and the brittleness index evaluation model based on dynamic and static mechanical parameter conversion were established for the research horizon of No.3 coal bed in Zhengzhuang Block. The brittleness index of coal reservoir in the study area was comprehensively evaluated by elastic parameter method. By this way, it is found that the brittleness index of coal bed in single well is obviously affected by “boundary effect” …

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Volcano Opto-Acoustics: Mapping The Infrasound Wavefield At Yasur Volcano (Vanuatu), J. B. Johnson, T. Boyer, L. M. Watson, J. F. Anderson Apr 2023

Volcano Opto-Acoustics: Mapping The Infrasound Wavefield At Yasur Volcano (Vanuatu), J. B. Johnson, T. Boyer, L. M. Watson, J. F. Anderson

Geosciences Faculty Publications and Presentations

We explore the capabilities of volcano opto-acoustics, a promising technique for measuring explosion and infrasound resonance phenomena at open-vent volcanoes. Joint visual and infrasound study at Yasur Volcano (Vanuatu) demonstrate that even consumer-grade cameras are capable of recording infrasound with high fidelity. Passage of infrasonic waves, ranging from as low as 5 Pa to hundreds of Pa, from both explosions and persistent tremor, pressurizes and depressurizes ambient plumes inducing visible vaporization and condensation respectively. Optical tracking of these pressure wavefields can be used to identify spectral characteristics, which vary within Yasur's two deep craters and are distinct for explosion and …

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Threshold Segmentation Method Of Ct Scanning Data Of Coal And Rock Samples Considering Beam Hardening Effect And Its Application, Wang Kai, Fu Qiang, Xu Chao, Ai Zibo, Wang Lei, Shu Longyong Apr 2023

Threshold Segmentation Method Of Ct Scanning Data Of Coal And Rock Samples Considering Beam Hardening Effect And Its Application, Wang Kai, Fu Qiang, Xu Chao, Ai Zibo, Wang Lei, Shu Longyong

Coal Geology & Exploration

Beam hardening is a common phenomenon in the application of industrial computerized tomography (ICT). It can cause different grayscale values in components with the same density, which affects the threshold segmentation and later reconstruction of components seriously. Herein, study was conducted on the distribution law of grayscale values under the effect of beam hardening, so as to segment the CT scanning data of coal and rock samples under the beam hardening effect accurately. Through the study, it is found that the change in grayscale value on the grayscale beam could truly reflect the change in component density, which is proved …

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Sedimentary Coal-Controlling Effect And Coal-Forming Model Of Paleogene Coal Measures In Paralic Faulted Basin：A Case Study Of Huangxian Basin, Shandong Province, Wu Yue, Wang Dongdong, Wang Hailiang, Liu Haiyan, Li Zengxue, Zheng Xue Apr 2023

Sedimentary Coal-Controlling Effect And Coal-Forming Model Of Paleogene Coal Measures In Paralic Faulted Basin：A Case Study Of Huangxian Basin, Shandong Province, Wu Yue, Wang Dongdong, Wang Hailiang, Liu Haiyan, Li Zengxue, Zheng Xue

Coal Geology & Exploration

There are abundant coal-type oil and gas resources in Chinese sea area, but few researches have been conducted on the coal-type source rock, which seriously restricts the exploration of coal-type oil and gas resources in the sea area. Herein, this study on sedimentary coal-controlling effect and coal-forming model was carried out based on Huangxian Basin that is a paralic faulted basin with same coal-forming period, similar geological conditions and high degree of research for the coal basins in the sea area. Specifically, the pattern, evolution and sedimentary coal-controlling effect of paleogeography during the coal-forming period were reconstructed with full consideration …

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Deterioration Characteristics Of Water-Rock Interaction On Combustion Metamorphic Rocks In Northern Shaanxi, Hu Xin, Sun Qiang, Yan Changgen, Zhao Chunhu, Wang Shaofei Apr 2023

Deterioration Characteristics Of Water-Rock Interaction On Combustion Metamorphic Rocks In Northern Shaanxi, Hu Xin, Sun Qiang, Yan Changgen, Zhao Chunhu, Wang Shaofei

Coal Geology & Exploration

There are a lot of combustion metamorphic (CM) rocks formed by high temperature baking of coal fires in the border area of Shaanxi, Shanxi and Inner Mongolia in the northeastern margin of Ordos Basin. Compared with the virgin rock, the rock mass subjected to combustion metamorphism is broken in structure, with pores developed, and a large number of dangerous rock masses are formed under the long-term water-rock interaction. Herein, 50 dry-wet cycle experiments were carried out with the CM rocks in Daliuta Area of Shenmu in Shaanxi Province. Meanwhile, the changes in the physical and mechanical properties of CM rocks …

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Ecological Natural Restoration And Its Artificial Promotion Mode In Coal Mining Area, Liu Wei, Yin Qinrui, Liu Xianghong Apr 2023

Ecological Natural Restoration And Its Artificial Promotion Mode In Coal Mining Area, Liu Wei, Yin Qinrui, Liu Xianghong

Coal Geology & Exploration

The natural ecological restoration is an important direction of the national ecological restoration policy. Taking limited artificial measures to promote the natural ecological restoration in coal mining areas is in line with the actual engineering requirements under the context of "double carbon" goal and thus has a better prospect in market application. Herein, the research results in terms of natural ecological restoration were sorted out systematically for the three main types of damaged land in the coal mining areas. Meanwhile, the concept connotation of artificial promotion of natural restoration was studied and analyzed. Besides, the governance mode by zone and …

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