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Application Of Integrated Geophysical Surveys In The Identification Of Hidden Fire Sources In Spontaneous Combustion Zones In Coal Seams, Ma Zijun, Yang Haiyan, Li Wenyu, Xu Yunlei, He Yunlan, Liu Zhuoming, Li Peng, Huang Jiu Dec 2023

Application Of Integrated Geophysical Surveys In The Identification Of Hidden Fire Sources In Spontaneous Combustion Zones In Coal Seams, Ma Zijun, Yang Haiyan, Li Wenyu, Xu Yunlei, He Yunlan, Liu Zhuoming, Li Peng, Huang Jiu

Coal Geology & Exploration

Spontaneous combustion in coal seams, a factor influencing the development of many mining areas in China, can cause severe coal resource loss and environmental pollution. The positioning and distribution identification of hidden fire sources can provide an important basis for coal mine enterprises to prepare prevention and control measures. They are also a hot research topic and challenge in the field of coal fire disasters. Suitable channels for ventilation and oxygen supply are necessary for spontaneous combustion in coal seams. When the oxidative heat release rate of coals exceeds the heat dissipation rate, coal temperature will rise until the occurrence …


Chromium-Contaminated Sites: Migration Characteristics And Monitoring Using Dual-Frequency Ip Method, Wei Kaiyao, Liu Zhimin, Liang Chen, Zhang Jie, Ma Qiang Dec 2023

Chromium-Contaminated Sites: Migration Characteristics And Monitoring Using Dual-Frequency Ip Method, Wei Kaiyao, Liu Zhimin, Liang Chen, Zhang Jie, Ma Qiang

Coal Geology & Exploration

Given that the migration process of chromium-contaminated sites is subjected to various uncertainties, it is difficult to investigate the migration characteristics and explore the monitoring process using experiments. Based on the basic law of groundwater flow and the migration mechanisms of pollutants, this study conducted a simulation analysis of the migration characteristics of static chromium contamination sources and the law of changes in the migration characteristics using the COMSOL software. Then, this study verified the reliability and accuracy of numerical forward simulations through physical simulation experiments on a static soil bin. Specifically, using the model of chromium contamination source migration …


Dual-Frequency Transmission Radio Wave-Based Exploration Method And Its Application, Fu Xianjie, Hu Ze'an, Wu Rongxin, Li Peng Dec 2023

Dual-Frequency Transmission Radio Wave-Based Exploration Method And Its Application, Fu Xianjie, Hu Ze'an, Wu Rongxin, Li Peng

Coal Geology & Exploration

Coal seams can act as the guided wave layers of high-frequency electromagnetic waves, and radio wave perspective technology can be used to detect geological structures within coal seams of a working face. Presently, radio wave perspective methods usually use a single frequency, leading to some problems such as improper frequency selection and limited detection accuracy in the exploration of mining faces. In response, this study developed a dual-frequency transmission radio wave-based exploration method. Based on theoretical analysis, as well as the field strength of dual-frequency perspective and attenuation coefficient, this study derived the calculation formula for the absorption factor γ …


The Application Of The Opposing Coils Transient Electromagnetic Method And Microtremor Survey Method In Shallow Karst Detection, Zhang Xueliang, Xie Tao, Zhou Wei, Gao Hui, Deng Dong, Qu Jingyi Dec 2023

The Application Of The Opposing Coils Transient Electromagnetic Method And Microtremor Survey Method In Shallow Karst Detection, Zhang Xueliang, Xie Tao, Zhou Wei, Gao Hui, Deng Dong, Qu Jingyi

Coal Geology & Exploration

Concealed karsts frequently lead to disasters such as ground collapse, water reservoir seepage, and tunnel water inrush. Identifying the distribution and development of karsts in advance holds great significance for guiding engineering design and construction in karst areas. Geophysical methods rank among the most effective methods for karst detection. Given the problems of karst development, limited space, and serious electromagnetic interference in the tank farms of the Longkou Port, Shandong Province, this study explored shallow karsts in these farms through the joint application of the opposing coils transient electromagnetic (OCTEM) method and the microtremor survey method. Firstly, surface scanning was …


Advances In Research On Active Faults And Exploration Of Relevant Frontier Scientific Problems, Xu Xiwei, Li Feng, Cheng Jia, Liu Baojin, Chen Guihua, Li Kang, Ren Junjie, Jia Qichao Dec 2023

Advances In Research On Active Faults And Exploration Of Relevant Frontier Scientific Problems, Xu Xiwei, Li Feng, Cheng Jia, Liu Baojin, Chen Guihua, Li Kang, Ren Junjie, Jia Qichao

Coal Geology & Exploration

This study reviewed the approval and initiation processes and major research contents of China's active fault-related projects, such as the urban active fault survey projects, large-scale mapping programs of active faults, and the earthquake hazard assessment of active faults in key earthquake monitoring and prevention areas. By combining the scientific investigation results of the surface rupture zones induced by strong earthquakes over the past 20 years, this study elaborated on significant advances achieved in the following aspects: the survey and positioning techniques for concealed active faults under strong-noise and weak-signal conditions, the quantitative identification techniques for fault activity, theories and …


Application Of High-Precision Lidar Technology In Research On Active Fault-Induced Offset Geomorphic Features - A Case Study Of The Juxian-Tancheng Segment Of The Yishu Fault Zone, Yang Bin, Wang Hualin, Wu Hongbin, Ge Fugang, Zou Hao, Su Sili Dec 2023

Application Of High-Precision Lidar Technology In Research On Active Fault-Induced Offset Geomorphic Features - A Case Study Of The Juxian-Tancheng Segment Of The Yishu Fault Zone, Yang Bin, Wang Hualin, Wu Hongbin, Ge Fugang, Zou Hao, Su Sili

Coal Geology & Exploration

The Tancheng-Lujiang fault zone (also referred to as the TanLu fault zone), one of the most significant large-scale active faults in eastern China, has great seismogenic potential while passing through several cities with the activities and accumulation of human beings. To investigate the geometric distribution and activity characteristics of the TanLu fault zone, this study focused on the Juxian-Tancheng segment of the Yishu fault zone—a part of the TanLu fault zone. Given the vegetation coverage in eastern China, airborne light detection and ranging (LiDAR) and terrestrial laser scanning were employed to collect high-precision topographic data of the Zuoshan (Yibujian), Zhonghuashan, …


Table Of Contents, The Editors Dec 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Optimization Of Data Acquisition Parameters For Deep Seismic Reflection Surveys In Complex Terrain, Yan Yunxiang, Li Pei, Zhi Min, Liu Jianda, Wang Zichen, Zhang Ying, Pei Gendi, Li Linyuan, Mou Qi, Jia Jin Dec 2023

Optimization Of Data Acquisition Parameters For Deep Seismic Reflection Surveys In Complex Terrain, Yan Yunxiang, Li Pei, Zhi Min, Liu Jianda, Wang Zichen, Zhang Ying, Pei Gendi, Li Linyuan, Mou Qi, Jia Jin

Coal Geology & Exploration

Fujian, located in the orogen region of the coastal areas of southeast China, exhibits well-developed structures and complex surface conditions, which make deep seismic reflection surveys challenging. In response to the diversity and complexity of seismogeological conditions in Fujian, this study optimized the seismic excitation means based on previous deep seismic surveys. Specifically, the combination of large, medium, and small guns was transitioned into the layout of normal guns (spacing of shot points: 600 m) and large shots (spacing of shot points: 15 km), leading to enhanced folds of large shots. Through simulation analysis, this study calculated the spacing of …


Mechanical Behavior And Failure Response Characteristics Of Hard Sandstones Considering Bedding Dip Angles, Song Zhanping, Liu Hongke, Zheng Fang, Cheng Yun, Sun Yinhao, Song Wanxue Dec 2023

Mechanical Behavior And Failure Response Characteristics Of Hard Sandstones Considering Bedding Dip Angles, Song Zhanping, Liu Hongke, Zheng Fang, Cheng Yun, Sun Yinhao, Song Wanxue

Coal Geology & Exploration

This study focuses on the mechanical behavior and failure responses of hard sandstones considering bedding dip angles. Through uniaxial compression tests of hard sandstones with different bedding dip angles, this study delved into the influence of bedding dip angles on the mechanical behavior of hard sandstones and the relationship between the bedding dip angles and fractal characteristics of hard sandstone fragments. The test results show that bedding dip angles produced negligible effects on the type of the stress-strain curves of hard sandstones. However, low dip angles (0°, 22.5°, and 45°) corresponded to unimodal curves, while high dip angles (67.5° and …


Coal-Based Solid Waste From The Panyi Mine In The Huainan Mining Area: Fine-Scale Chemical Structure And Ecological Risk Assessment Of Heavy Metals, Yin Wenwen, Zhang Liqun, Ding Dan, Shan Shifeng, Chen Yongchun, An Shikai, Zheng Liugen Dec 2023

Coal-Based Solid Waste From The Panyi Mine In The Huainan Mining Area: Fine-Scale Chemical Structure And Ecological Risk Assessment Of Heavy Metals, Yin Wenwen, Zhang Liqun, Ding Dan, Shan Shifeng, Chen Yongchun, An Shikai, Zheng Liugen

Coal Geology & Exploration

The utilization of clean coal-based solid waste is a pressing issue in the ecological construction of mining areas. To address this issue, the key is to ascertain the structures and morphology of heavy metals in coal-based solid waste. This study investigated the coal gangue and fly ash samples from the Panyi Mine in the Huainan mining area, Anhui Province. First, this study characterized the coal-based solid waste using microanalysis methods, such as X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Then, it examined the fine-scale chemical structure and heavy metal dissemination …


Current States , Prediction And Prevention Suggestions For Water Hazard Accidents In China’S Coal Mines, Sun Wenjie, Li Wenjie, Ning Dianyan, Ren Lingfeng Dec 2023

Current States , Prediction And Prevention Suggestions For Water Hazard Accidents In China’S Coal Mines, Sun Wenjie, Li Wenjie, Ning Dianyan, Ren Lingfeng

Coal Geology & Exploration

At present, the pattern of coal resource development in China has changed, but the water hazard accidents that restrict the safety production of coal mine still occur from time to time. In order to explore the characteristics and laws of water hazard accidents in coal mines in China and scientifically study and judge the evolution trend of water hazard accidents, study was performed in terms of the year, region, accident level and influencing factors of water hazard accidents, with the nationwide water hazard accidents from 2001 to 2022 as the statistical objects. Meanwhile, the Long Short-Term Memory (LSTM) model was …


Zagamiite, Caal2si3.5o11, The Hexagonal High-Pressure Cas Phase With Dominant Si, As A Mineral From Mars, Chi Ma, Oliver Tschauner, John R. Beckett, Eran Greenberg, Vitali B. Prakapenka Dec 2023

Zagamiite, Caal2si3.5o11, The Hexagonal High-Pressure Cas Phase With Dominant Si, As A Mineral From Mars, Chi Ma, Oliver Tschauner, John R. Beckett, Eran Greenberg, Vitali B. Prakapenka

Geoscience Faculty Research

Within the Ca-Al-silicate system, dense, layered hexagonal phases occur at high temperatures and pressures between 20 and 23 GPa. They have been observed both in nature and in experiments. In this study, we describe the endmember with a dominant sixfold coordinated Si as a mineral zagamiite (IMA 2015-022a). This new mineral identified in Martian meteorites has a general formula of (Ca,Na)(Al,Fe,Mg)2(Si,Al,□)4O11, thus defining CaAl2Si3.5O11 as a previously unknown endmember of the hexagonal CAS phases. Zagamiite assumes space group P63/mmc with a unit cell of a = 5.403(2) Å, c = 12.77(3) Å, V = 322.9(11) Å3, and Z = 2. …


The Magmatic Origin Of The Columbia River Gorge, Usa, Nathaniel Klema, Leif Karlstrom, Charles Cannon, Chengxin Jiang, Jim O'Connor, Ray E. Wells, Brandon Schmandt Dec 2023

The Magmatic Origin Of The Columbia River Gorge, Usa, Nathaniel Klema, Leif Karlstrom, Charles Cannon, Chengxin Jiang, Jim O'Connor, Ray E. Wells, Brandon Schmandt

Geology Faculty Publications and Presentations

Along subduction zones, high-relief topography is associated with sustained volcanism parallel to the plate margin. However, the relationship between magmatism and mountain building in arcs is poorly understood. Here, we study patterns of surface deformation and correlated fluvial knickpoints in the Columbia River Gorge to link long-term magmatism to the uplift and ensuing topographic development of the Cascade Range. An upwarped paleochannel exposed in the walls of the Gorge constrains unsteady deep magma flux, the ratio of intrusive to extrusive magmatic contributions to topography, and the impact of magmatism on Columbia River incision since 3.5 million years ago. Geophysical data …


Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti Dec 2023

Reverse Pseudo-Gours: A New Sub-Type Of Folia Observed In The Nerja Cave (Se Spain), Cristina Liñán Baena, Concepción Jiménez De Cisneros, Yolanda Del Rosal, Paolo Forti

International Journal of Speleology

A new sub-type of folia named “reverse pseudo-gour” has been observed and described in the Nerja Cave, southern Spain. It consists of fairly vertical, thin barriers (about 5 mm high and 2 mm thick) that develop on the underside of a sub-horizontal surface (shelfstone) and grow in the opposite direction to normal gours (rimstone dams), generating sinuous shapes. Their mineral composition is essentially calcium carbonate, although globular aggregates composed of clay and phosphate minerals have also been identified. The genesis and evolution of these reverse pseudo-gours occur just at the air-water interface and are controlled by (1) the sub-horizontality of …


Studying The Impact Of The Geospace Environment On Solar Lithosphere Coupling And Earthquake Activity, Dimitar Ouzounov, Galina Khachikyan Dec 2023

Studying The Impact Of The Geospace Environment On Solar Lithosphere Coupling And Earthquake Activity, Dimitar Ouzounov, Galina Khachikyan

Mathematics, Physics, and Computer Science Faculty Articles and Research

In solar–terrestrial physics, there is an open question: does a geomagnetic storm affect earthquakes? We expand research in this direction, analyzing the seismic situation after geomagnetic storms (GMs) accompanied by the precipitation of relativistic electrons from the outer radiation belt to form an additional radiation belt (RB) around lower geomagnetic lines. We consider four widely discussed cases in the literature for long-lived (weeks, months) RBs due to GMs and revealed that the 1/GMs 24 March 1991 with a new RB at L~2.6 was followed by an M7.0 earthquake in Alaska, 30 May 1991, near footprint L = 2.69; the 2/GMs …


Studi Alimentari Italiani E Geologia: Vino E Vulcani Da Diverse Prospettive, Maria Varriale Gomez Dec 2023

Studi Alimentari Italiani E Geologia: Vino E Vulcani Da Diverse Prospettive, Maria Varriale Gomez

Italian Renaissance Foodways

Nel mio progetto di integrazione avanzata, mi impegnerò in un'esplorazione interdisciplinare del vino. Analizzerò il vino utilizzando gli studi alimentari italiani e la geologia, concentrandomi in particolare sugli effetti che i vulcani hanno avuto sul vino in Italia sin dal Medioevo e dal Rinascimento. Nel corso della storia, il vino è stato una parte cruciale della cultura italiana e i vulcani del paese hanno influenzato la produzione della bevanda in modi diversi come la varietà delle uve coltivate e il suo sapore basato sulla composizione del terreno vulcanico. Le numerose regioni in Italia producono vino diverso in gran parte a …


Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery Dec 2023

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery

Earth and Planetary Sciences ETDs

The 1.2 Ma Valles Caldera in north-central New Mexico hosts a young igneous volcanic hydrothermal system after the model proposed in Goff and Janik (2000). The Sulphur Springs area within Valles Caldera is an acid-sulfate area typical of this model, discharging acidic waters (pH 1.5-3) formed by oxidation of magmatic H2S at the surface. We report on samples obtained from springs and streams collected between October 2021 and May 2023 in the Sulphur Creek and Alamo watersheds. Sulphur Creek receives input from Sulphur Springs and exhibits low pH (2-4) and high concentrations of Al (≤110 mg/L), Fe (≤60 …


Transport And Mixing Of Water Masses Across The Southeast Caribbean Ocean Imaged By Seismic Reflection Data, Joseph Renzaglia Dec 2023

Transport And Mixing Of Water Masses Across The Southeast Caribbean Ocean Imaged By Seismic Reflection Data, Joseph Renzaglia

Earth Sciences Theses and Dissertations

The Caribbean Sea serves as a major pathway for global thermohaline circulation (THC), which is a complex and vital component of the Earth’s climate system, influencing global heat distribution and oceanic circulation. Though relatively stratified, it is the boundary layer that distributes mass and temperature between the surface waters and the deep ocean where we observe various multiscale mixing processes from mesoscale to fine-scale. In regions where bathymetry is shallower and mechanical mixing forces, such as winds and tides, are more dominant, diapycnal diffusivity is typically stronger, driving vertical mixing. This type of mixing occurs at small scales, typically as …


Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton Dec 2023

Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton

Electronic Theses and Dissertations

Noctis Labyrinthus (NL) is an extensional trough network connecting the Tharsis rise and Valles Marineris on Mars. Chaotic terrains are a group of polygonally-fractured surface features commonly associated with subsidence due to rapid fluid loss within the subsurface. Polygonal surface patterns are seen at both sites, where geometric topographic highs are bounded by low troughs. Lineaments, topography, and geomorphology of NL and chaotic terrains were analyzed to determine tectonics and fluid influence in the formation and evolution of both sites. NL shows preferential fracture patterns associated with regional extension. Lineaments within chaotic terrains do not show cumulative preferential trends but …


Observed Impacts Of Large Wind Farms On Grassland Carbon Cycling, Donghai Wu, Steven M. Grodsky, Wenfang Xu, Naijing Liu, Rafael M. Almeida, Liming Zhou, Lee M. Miller, Somnath Baidya Roy, Geng Xia, Anurag A. Agrawal Dec 2023

Observed Impacts Of Large Wind Farms On Grassland Carbon Cycling, Donghai Wu, Steven M. Grodsky, Wenfang Xu, Naijing Liu, Rafael M. Almeida, Liming Zhou, Lee M. Miller, Somnath Baidya Roy, Geng Xia, Anurag A. Agrawal

School of Earth, Environmental, & Marine Sciences Faculty Publications

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Celestial Bodies, Rebecca L. Rand, Mark Popinchalk Dec 2023

Celestial Bodies, Rebecca L. Rand, Mark Popinchalk

Capstones

Most of us will never come close to touching space. But space touches us every day. On Celestial Bodies, journalist Rebecca Rand and astronomer Mark Popinchalk explore the ways outer space interacts with life on earth.

In Episode 1, hosts Rebecca Rand and Mark Popinchalk explore how, for millions of years, trees have been recording celestial events in space. Within the rings of their trunks, trees store radiation from solar flares, supernovae, and changes in the earth’s magnetic field. The hosts talk to Dr. Ben Pope to learn more about what we can discover by looking at radioactive molecules …


Paleoclimate Of The Peruvian Andean Highlands During The Late Holocene, Jarunetr Sae-Lim Dec 2023

Paleoclimate Of The Peruvian Andean Highlands During The Late Holocene, Jarunetr Sae-Lim

Arts & Sciences Graduate Student Theses and Dissertations

The tropical and central Andean highlands (>4,000 m above sea level) supply critical freshwater resources to the Amazon Basin, supporting large communities in mountain regions and lowlands. Due to the scarcity of historical weather data spatially and temporally, it is challenging to quantify hydroclimate and environmental responses to anthropogenic climate change. Paleoclimate reconstruction and modeling can provide critical insights into key hydroclimate processes and how hydroclimate in this region has responded to climate change and variability through time. However, biomarker-based paleoclimate proxy reconstructions are still very rare in this region. This dissertation quantifies local-scale and regional-scale hydroclimate and environmental …


Analyzing The Shark Paleoecology Of Coastal Georgia From The Miocene And Pliocene Epochs, Joshua Lee Clark, Benjamin Angalet Dec 2023

Analyzing The Shark Paleoecology Of Coastal Georgia From The Miocene And Pliocene Epochs, Joshua Lee Clark, Benjamin Angalet

Georgia Journal of Science

The field of shark paleoecology often yields indecisive conclusions based on the limited fossilization of their anatomical structures, with the exception of their teeth. The majority of the Atlantic coast has been studied regarding the presence of certain prehistoric shark species from the Miocene, Pliocene, and Pleistocene epochs. However, information pertaining to the Georgia coast and understanding its potential community structure is relatively understudied. This study was conducted in which thousands of fossil shark specimens and subsequent marine fauna were collected from dredge spoils created by the US Army Corps of Engineers (USACE): Savannah District. A total of 5,127 fossil …


Response Differences Of Two Maize Hybrid Varieties To The Application Of Bioagent-Ameliorant And Chicken Manure In Fertile Soil, Endang Kantikowati, Karya, Yudi Yusdian, Dian Murti Minangsih, Tien Turmuktini, Erna Yuliani, Fija Faujiah Dec 2023

Response Differences Of Two Maize Hybrid Varieties To The Application Of Bioagent-Ameliorant And Chicken Manure In Fertile Soil, Endang Kantikowati, Karya, Yudi Yusdian, Dian Murti Minangsih, Tien Turmuktini, Erna Yuliani, Fija Faujiah

Jurnal Kultivasi

To ensure adequate nutrition for the growth of maize (Zea mays L.) in sustainable agriculture, it is necessary to apply bio-agent soil conditioner and manure. This study aims to determine the effect of doses of bioagent-ameliorant and chicken manure on growth and yield components. The research was conducted in highland with an altitude 800 m above sea level. This study used an experimental method with two sets of experiments, namely experiments using one and two-cobs maize cultivars. The experiment used a randomized block design (RBD) with two treatment factors and three replications. The first treatment factor was the dose of …


Free-Radical Scavenging Activity And Total Phenolic Compounds Of Red And Green Poinsettia Leaves (Euphorbia Pulcherrima Willd.) From Lombok Island, Handa Muliasari, Baiq Sopiah, Emmy Yuanita, Baiq Nila Sari Ningsih Dec 2023

Free-Radical Scavenging Activity And Total Phenolic Compounds Of Red And Green Poinsettia Leaves (Euphorbia Pulcherrima Willd.) From Lombok Island, Handa Muliasari, Baiq Sopiah, Emmy Yuanita, Baiq Nila Sari Ningsih

Makara Journal of Science

To determine the free-radical scavenging activity and total phenolic content of the ethanol extract of Poinsettia leaves (Euphorbia pulcherrima Willd.) from Lombok Island, we used the 1,1-diphenyl-2-picrylhydrazyl method and expressed the total phenolic content as gallic acid equivalent (GAE) per gram of ethanol extract. The results show the strong antioxidant activity (79.77 ppm) of the ethanol extract of red Poinsettia leaves and the moderate antioxidant activity of green Poinsettia leaves (118.350 ppm). The ethanol extracts of red and green Poinsettia leaves possessed an average of 63.276 ± 0.228 and 22.715 ± 0.090 mg GAE/g extract total phenolic contents, respectively. …


Enzymatic Screening And Genotypic Characterization Of Thermophilic Bacteria From The Hot Springs Of Sarawak, Malaysia, Seng Chiew Toh, Samuel Lihan, Sui Sien Leong, Azizul Hakim Lahuri, Wai Cheong Woon, Wing Woh Ng Dec 2023

Enzymatic Screening And Genotypic Characterization Of Thermophilic Bacteria From The Hot Springs Of Sarawak, Malaysia, Seng Chiew Toh, Samuel Lihan, Sui Sien Leong, Azizul Hakim Lahuri, Wai Cheong Woon, Wing Woh Ng

Makara Journal of Science

Owing to their eccentric thermostable ability, thermophiles are among the most utilized extremophiles in various industries, such as manufacturing, and clinical research. Researchers believe that many unknown thermophiles are yet to be discovered. This study aimed to genotypically characterize the diversity of thermophiles and screen them for the potential production of enzymes in the recreational hot springs located at Northwest Coast of Borneo. Water samples were collected at 45 °C–50 °C from Annah Rais and Panchor hot springs during the sampling period from January 2018 to January 2019. Three samples (water and sediment) were collected twice in a 3-week interval …


Quantifying Current Soil Brine Contamination Within The Smackover Oil Field In Arkansas Using Multispectral Digital Imagery, Victoria Williams Dec 2023

Quantifying Current Soil Brine Contamination Within The Smackover Oil Field In Arkansas Using Multispectral Digital Imagery, Victoria Williams

Electronic Theses and Dissertations

A remote sensing study was performed to quantify current soil brine contamination across the historic Smackover Oil Field in south-central Arkansas, United States. The oil field was established in 1922 and was not subject to the future waste regulations created by the Arkansas Oil and Gas Commission. Brine is a waste product of oil manufacturing which contains water with high salt levels. The storage and transport of brine in the oil field created landscape scarring across the study area.

Landsat 9 multispectral digital imagery was utilized to create supervised classification maps based on earthen pits and creek scarring across the …


Morphological And Structural Characterization Of Shortening Landforms On Mars, Leta Mccullough Dec 2023

Morphological And Structural Characterization Of Shortening Landforms On Mars, Leta Mccullough

Theses and Dissertations

The lithosphere of Mars accommodates shortening through folding and faulting, producing landforms qualitatively categorized as wrinkle ridges or lobate scarps. However, we lack a deep understanding of the morphological differences between these landforms. This study aimed to develop a quantitative model for shortening landform classification based on surface morphology and subsurface architecture. We developed this model by mapping 100 landforms in a GIS, recording parameters for each landform. We conducted a Discriminant Function Analysis (DFA) using these morphometrics. This DFA produced a predictive linear function for categorizing wrinkle ridges and lobate scarps. We then modeled the subsurface structural geology of …


Investigating The Effects Of A Southward Flow In The Southeastern Florida Shelf Using Robotic Instruments, Alfredo Quezada Dec 2023

Investigating The Effects Of A Southward Flow In The Southeastern Florida Shelf Using Robotic Instruments, Alfredo Quezada

All HCAS Student Capstones, Theses, and Dissertations

We deployed a Slocum G3 glider fitted with an acoustic Doppler current profiler (ADCP), a Conductivity-Temperature-Depth sensor (CTD), optics sensor channels, and a propeller on the Southeastern Florida shelf. The ADCP and CTD provide continuous measurements of Northern and Eastern current velocity components, salinity, temperature, and density, throughout the water column in a high-current environment. The optics sensor channels are able to provide measurements of chlorophyll concentrations, colored dissolved organic matter (CDOM), and backscatter particle counts. Additionally, for one of the glider deployments, we deployed a Wirewalker wave-powered profiling platform system also fitted with an ADCP and a CTD in …


Prevalence, Faunal Composition, And Vertical Distribution Of Bioluminescence In The Pelagic Gulf Of Mexico: Fishes, Crustaceans, Cephalopods And Gelatinous Megaplankton, Devynne M. Brown Dec 2023

Prevalence, Faunal Composition, And Vertical Distribution Of Bioluminescence In The Pelagic Gulf Of Mexico: Fishes, Crustaceans, Cephalopods And Gelatinous Megaplankton, Devynne M. Brown

All HCAS Student Capstones, Theses, and Dissertations

Bioluminescence is the phenomenon of light emission by living organisms. It occurs through a chemical reaction within an organism and serves various purposes. The diversity of bioluminescent capabilities and occurrence in unrelated taxa suggest that bioluminescence has evolved independently numerous times amongst taxa thriving in certain environments. One such environment is the deep ocean, where little to no sunlight penetrates the water column, specifically in the mesopelagic (200-1000 m depth) and bathypelagic (> 1000 m) zones. The mesopelagic and bathypelagic zones have been extensively sampled and well documented in the Gulf of Mexico (GoM), one of the few places globally …