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Articles 91 - 120 of 11735
Full-Text Articles in Entire DC Network
Three-Dimensional, Collaborative Detection Approach For Fire Zones In Shallowly Buried Coal Seams And Its Application, Fan Kaixiang, Hu Xiangming, Hong Haibo, Dong Hao, Yu Shijian, Wei Zhengrong, Guo Yongxiang
Three-Dimensional, Collaborative Detection Approach For Fire Zones In Shallowly Buried Coal Seams And Its Application, Fan Kaixiang, Hu Xiangming, Hong Haibo, Dong Hao, Yu Shijian, Wei Zhengrong, Guo Yongxiang
Coal Geology & Exploration
Objective Fire zones in shallowly buried coal seams have long restricted safe and efficient coal mining due to their considerably hidden and hazardous nature. However, individual methods for fire source detection are susceptible to geological conditions and ambient noise, suffering from limited detection dimensions and the presence of technical blind spots. Therefore, they fail to accurately localize hidden fire sources in shallow coal seams. Methods This study proposes a three-dimensional, collaborative multi-source detection approach that combines the self-potential (SP) method, the radon measurement (Rn) method, electrical resistivity tomography (ERT; also referred to as high-density resistivity method), and the transient electromagnetic …
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Evaluation Of Deep High-Quality Reservoirs Based On The Fuzzy Analytic Hierarchy Process And The Entropy Weight Method: A Case Study Of The No. 8 Coal Seam In The East-Central Ordos Basin, Yan Ronghui, Xu Hao, Hu Jianling, Li Xiaotian, Jiao Pengshuai, Huang Daojun, Chen Shida, Wu Xiaozhuo
Coal Geology & Exploration
Objective Significant breakthroughs have been achieved in the exploration and exploitation of coalbed methane (CBM) in the deep No. 8 coal seam within the east-central Ordos Basin. However, a comprehensive quantitative evaluation system at the regional scale is yet to be established for reservoirs in the No. 8 coal seam. Methods Based on logs, coal quality, and measured physical property data from over 270 wells in the east-central Ordos Basin, this study developed a comprehensive evaluation system for deep coal reservoirs using the fuzzy analytic hierarchy process combined with the entropy weight method. Specifically, the evaluation system consisted of nine …
Co2 Fracturing Stimulation Technology For Low-Yield Directional Coalbed Methane Wells And Its Applications, Zhang Junsheng, Cao Yunxing, Wang Li, Wang Zhongbin, Yang Baige, Shi Bin, Cao Yongsen, Xu Fengyi
Co2 Fracturing Stimulation Technology For Low-Yield Directional Coalbed Methane Wells And Its Applications, Zhang Junsheng, Cao Yunxing, Wang Li, Wang Zhongbin, Yang Baige, Shi Bin, Cao Yongsen, Xu Fengyi
Coal Geology & Exploration
Background In China, low-yield coalbed methane (CBM) wells represent a high proportion of approximately 57% (over 12400 wells), generally encountering challenges such as low pressure, dry reservoirs, and near-wellbore formation damage and blockage. Conventional hydraulic fracturing is prone to induce water blocking damage, while treatments such as acidification offer only limited blockage-removing radii. Therefore, existing techniques are insufficient to achieve blockage removal and permeability enhancement while avoiding reservoir damage. Exploring efficient waterless stimulation technologies suitable for these low-yield wells is of great significance for increasing CBM production and advancing the CBM industry. Methods This study investigated directional wells PXC-03 and …
Water Hazards In Thick Floor Aquicludes For Coal Mining Above Confined Aquifers In North China-Type Coalfields: Patterns, Mechanisms, And Prevention And Control, Meng Haopeng, Yin Shangxian, Lian Huiqing, Yin Huichao, Hou Enke, Zhang Yi’An, Wang Zhuo, Jin Zidong, Cai Xiangjun, Cao Min, Wang Jianguang
Water Hazards In Thick Floor Aquicludes For Coal Mining Above Confined Aquifers In North China-Type Coalfields: Patterns, Mechanisms, And Prevention And Control, Meng Haopeng, Yin Shangxian, Lian Huiqing, Yin Huichao, Hou Enke, Zhang Yi’An, Wang Zhuo, Jin Zidong, Cai Xiangjun, Cao Min, Wang Jianguang
Coal Geology & Exploration
Background Water hazards in coal seam floors represent a core challenge restricting the exploitation of deep coal resources in North China-type coalfields. As coal mining extends to greater depths, previous studies and experience exhibit limited applicability in the pattern classification, mechanism interpretation, and prevention and control of water hazards in thick floor aquicludes. Therefore, there is an urgent need to make breakthroughs and improvements in these three aspects.Methods Using several methods, including case-based induction, theoretical analysis, numerical simulation, and technical summary, this study developed a classification system based on parallel multiple criteria for floor water hazards by combining available …
Assessing Fault-Induced Floor Water Inrushes Based On Improved Water Inrush Coefficients, Jiao Bin, Tan Wenfeng, Li Hongsheng, Chen Juntao, Gao Hongbing, Zhao Zizhang, Wu Fangcan
Assessing Fault-Induced Floor Water Inrushes Based On Improved Water Inrush Coefficients, Jiao Bin, Tan Wenfeng, Li Hongsheng, Chen Juntao, Gao Hongbing, Zhao Zizhang, Wu Fangcan
Coal Geology & Exploration
Background As coal mining in mines constantly expands to greater depths, water hazards in the Ordovician limestone aquifers of coal seam floors pose a serious threat to the mining of coal seams in lower formations. Fault reactivation represents a primary factor inducing water inrushes. However, the original water inrush coefficient (T = p/M) suffers from certain limitations when used to assess the water inrushes in areas with faults. Methods Four models of floor water inrushes induced by non-penetrating faults (i.e., concealed hydraulically conductive faults, concealed isolated faults, and exposed faults) and penetrating faults were constructed, and …
Numerical Simulations And Dispersion Analysis Of 3d In-Seam Waves Based On Finite Difference Method On Curvilinear Grids, Liu Dan, Ren Zhiming
Numerical Simulations And Dispersion Analysis Of 3d In-Seam Waves Based On Finite Difference Method On Curvilinear Grids, Liu Dan, Ren Zhiming
Coal Geology & Exploration
Background With the comprehensive advancement in intelligent coal mine construction, creating high-precision, transparent geological models of coal seams and their surrounding strata has emerged as a prerequisite for intelligent coal mining. The accurate identification of concealed geological anomalies, such as folds and faults, within coal seams represents a key challenge in safe coal mining. In-seam seismic exploration has become an important approach to detecting underground concealed structures owing to its advantages, including a considerable detection distance along coal seams, high precision, pronounced frequency dispersion effects, and facilitating the identification of waveform signatures. However, conventional methods for seam wave simulation are …
Table Of Contents, The Editors
Enhanced Adaptive Smith Predictor Control For Underground Coal Gasification With Long Time Delays, Tang Yang, Wu Qiong, Zhang Lei, Zhou Mingjun, Wan Min, Liao Zhuodong
Enhanced Adaptive Smith Predictor Control For Underground Coal Gasification With Long Time Delays, Tang Yang, Wu Qiong, Zhang Lei, Zhou Mingjun, Wan Min, Liao Zhuodong
Coal Geology & Exploration
Background Underground coal gasification (UCG) represents an in situ conversion technology used to convert solid coals into gaseous fuel. However, the reaction process during UCG exhibits significant time delays. Such a limitation will reduce the response capability of the UCG system and is prone to induce overshoot and oscillation, thereby increasing the system’s control difficulty and reducing its stability and dynamic performance. Method To address these issues, this study proposed an enhanced Smith predictor control algorithm based on a genetic algorithm and established a semi-physical experimental platform integrating a physical distributed control system DCS-Matlab for modeling. Using the platform, experiments …
Discovery And Implications For Ore Prospecting Of Gravitational Gliding Structures In The Lutang Coal-Based Graphite Mining Area, Hunan Province, China, Xiao Jincheng, Lu Jiang, Liu Zhiyu, Zhu Linying, Xiao Haibin, Li Long, Xiao Jing
Discovery And Implications For Ore Prospecting Of Gravitational Gliding Structures In The Lutang Coal-Based Graphite Mining Area, Hunan Province, China, Xiao Jincheng, Lu Jiang, Liu Zhiyu, Zhu Linying, Xiao Haibin, Li Long, Xiao Jing
Coal Geology & Exploration
Background Data from previous exploration and studies indicate that the Lutang coal-based graphite mining area in Hunan Province falls within the Lutang-Shatian synclinorium in terms of tectonic location, with coal-bearing strata dominated by the upper member of the Upper Permian Longtan Formation. Influenced by the intrusion of granites, coal seams adjacent to the Qitianling pluton on the eastern flank of the mining area have undergone contact metamorphism, forming coal-based graphite. Previous exploration results suggest that the Qitianling pluton has a maximum burial depth measured at an elevation of 0 m or less. However, with constant underground exposure in mines, previous …
Comparison Of Log-Based Coal Structure Identification Methods For Structurally Complex Areas: A Case Study Of The Huainan Mining Area, Zhang Zixin, Zhou Xiaozhi, Chen Xuehua
Comparison Of Log-Based Coal Structure Identification Methods For Structurally Complex Areas: A Case Study Of The Huainan Mining Area, Zhang Zixin, Zhou Xiaozhi, Chen Xuehua
Coal Geology & Exploration
Objective CO2 displacing coalbed methane (CBM) provides substantial environmental and energy benefits. However, differences in coal structures represent a key geological factor influencing the effectiveness of this technique. Constrained by the complex geological conditions for CBM occurrence and the impacts of multiple factors on the log responses of coal structures, traditional log-based methods for coal structure identification face challenges such as much human intervention, complex feature engineering, and poor adaptability. This study aims to achieve effective identification of complex coal structures within a single coal seam. Methods An asymmetric convolution kernel-based convolutional neural network (CNN) model for coal structure …
Heterogeneity And Its Controlling Effect On Coalbed Methane Productivity For Deep Coal Reservoirs In The Northern Part Of The Eastern Margin Of The Ordos Basin, Xi Zhaodong, Tang Shuheng, Wu Jian, Zhang Songhang, Zhao Hang, Chen Jiang, Li Yanfei
Heterogeneity And Its Controlling Effect On Coalbed Methane Productivity For Deep Coal Reservoirs In The Northern Part Of The Eastern Margin Of The Ordos Basin, Xi Zhaodong, Tang Shuheng, Wu Jian, Zhang Songhang, Zhao Hang, Chen Jiang, Li Yanfei
Coal Geology & Exploration
Objective With the continuous advancement in the exploration and exploitation of coalbed methane (CBM), the focus of research and practices is gradually shifting from shallow to deep parts. Deep CBM, an important unconventional natural gas resource, has become a strategic replacement to ensure energy security and prompt industrial development in China. However, deep coal reservoirs exhibit strong heterogeneities, posing a core geological challenge to their efficient exploration and development. Methods This study investigated the deep No. 8 coal seam in the northern part of the eastern margin of the Ordos Basin. By integrating multiple technical methods, including geostatistics, spatial interpolation, …
Helium Origin And Primary Factors Controlling Helium Enrichment For Bauxite Gas Reservoirs In The Longdong Area, Ordos Basin, Chen Keyu, Wang Xiaofeng, Liu Wenhui, Zhang Dongdong, Li Xiaofu
Helium Origin And Primary Factors Controlling Helium Enrichment For Bauxite Gas Reservoirs In The Longdong Area, Ordos Basin, Chen Keyu, Wang Xiaofeng, Liu Wenhui, Zhang Dongdong, Li Xiaofu
Coal Geology & Exploration
Objective Significant breakthroughs have been achieved in the exploration of bauxite gas reservoirs in the Taiyuan Formation, Longdong area, Ordos Basin. Bauxites are generally considered to hold great helium generation potential due to their relatively high uranium (U) and thorium (Th) contents. However, there remains a lack of quantitative studies on their actual contribution to helium abundance in natural gas in the area. Methods To determine dominant helium source rocks and mechanisms behind helium enrichment, this study investigated the bauxite gas reservoirs within the Taiyuan Formation in the Longdong area. Through analyses of the composition, carbon isotopes, and noble gas …
Damage And Fracture Field Evolution In The Overburden Of An Extremely Thick Coal Seam Under Multi-Layered Fully Mechanized Top-Coal Caving Mining, Zhang Cun, Fan Baiqiang, Ren Yiming, Zhao Ruihang, Peng Baoshan, Pan Weidong, Liu Shiqi
Damage And Fracture Field Evolution In The Overburden Of An Extremely Thick Coal Seam Under Multi-Layered Fully Mechanized Top-Coal Caving Mining, Zhang Cun, Fan Baiqiang, Ren Yiming, Zhao Ruihang, Peng Baoshan, Pan Weidong, Liu Shiqi
Coal Geology & Exploration
Objective Multi-layered fully mechanized top-coal caving mining represents a primary method for exploiting extremely thick coal seams. Quantitatively characterizing the damage patterns and fracture field evolution characteristics of the overburden in stopes subjected to high-intensity layered mining is critical to the safe production of coal mines. Methods The extremely thick B1 coal seam (average thickness: 53.59 m) in the No. 2 mine of the Dajing mining area in the Zhundong coalfield was selected as the engineering background. By integrating physical simulation using similar materials and numerical simulation, this study revealed the geometric and fractal characteristics of damage to the overburden …
Triaxial Shear Test-Derived Strength Model Of Deeply Buried Frozen Calcareous Clay Incorporating The Effect Of Unfrozen Water Content, Xing Lezhang, Rong Chuanxin, Chang Lei, Wang Bin, Deng Jiyuan
Triaxial Shear Test-Derived Strength Model Of Deeply Buried Frozen Calcareous Clay Incorporating The Effect Of Unfrozen Water Content, Xing Lezhang, Rong Chuanxin, Chang Lei, Wang Bin, Deng Jiyuan
Coal Geology & Exploration
Background The Huanghuai mining area represents an important coal base in eastern China. However, the Cenozoic calcareous clay in the area exhibits high plasticity, low permeability, and potential expansion and deformation during freezing, leading to unstable freezing performance. Consequently, artificial ground freezing (AGF) in the area generally faces a risk of cost surge or out of control due to the excessive thickness or limited strength of frozen walls.Methods This study investigated calcareous clay remolded based on soil samples from the Huanghuai mining area. Using a low-field nuclear magnetic resonance (LF-NMR) spectrometer and a high-pressure triaxial system, this study systematically …
Bp-Kan-Based Inversion Imaging For Borehole Resistivity Method And Its Application, Xu Zhongzhong, Yin Longlong, Cheng Jiulong, Xu Jinpeng, Lu Cunjin, Zhao Hongpeng
Bp-Kan-Based Inversion Imaging For Borehole Resistivity Method And Its Application, Xu Zhongzhong, Yin Longlong, Cheng Jiulong, Xu Jinpeng, Lu Cunjin, Zhao Hongpeng
Coal Geology & Exploration
Objective In the monitoring of coal seam mining-induced deformation and failure of surrounding rocks, the borehole resistivity method stands out due to its capacity for dynamic, three-dimensional (3D) full-space measurements. However, conventional resistivity inversion for the method is generally carried out using the least squares algorithm, leading to limited accuracy in practical engineering. In recent years, neural network-based inversion has demonstrated the potential for addressing this challenge, while its performance is yet to be further improved. Methods In this context, inversion imaging based on a back propagation-Kolmogorov-Arnold network (BP-KAN) was proposed for the borehole resistivity method, aiming to accurately monitor …
Design Of An Intelligent Failure Diagnosis And Early Warning System For Tunnel Drilling Rigs In Coal Mines, Song Haitao, Zhang Naiwen, Han Jian, Wu Min
Design Of An Intelligent Failure Diagnosis And Early Warning System For Tunnel Drilling Rigs In Coal Mines, Song Haitao, Zhang Naiwen, Han Jian, Wu Min
Coal Geology & Exploration
Objective In coal mines, harsh environments and complex geological conditions underground lead to frequent failures of tunnel drilling rigs. However, conventional techniques for failure diagnosis and early warning suffer from limitations in diagnostic accuracy, real-time performance, and interpretability. Therefore, these techniques are insufficient for both the rapid identification of the anomalous status of tunnel drilling rigs and the early warning of their potential failures. Methods Considering the complex underground environments in coal mines, this study developed an intelligent failure diagnosis and early warning system for tunnel drilling rigs in coal mines, placing a particular emphasis on key technologies for failure …
A Method For Optimizing The Digital Twin Model Of The Mechanical-Electro-Hydraulic System Of Cantilever Tunnel Boring Machines, Wang Yan, Jia Zeyu, Zhao Yihui, Wei Shirui, Zhang Xuhui, Zhao Youjun, Han Xiao
A Method For Optimizing The Digital Twin Model Of The Mechanical-Electro-Hydraulic System Of Cantilever Tunnel Boring Machines, Wang Yan, Jia Zeyu, Zhao Yihui, Wei Shirui, Zhang Xuhui, Zhao Youjun, Han Xiao
Coal Geology & Exploration
Objective Cantilever roadheaders represent roadway tunnelling equipment that integrates the deep coupling of mechanical, electrical, and hydraulic systems, and their control accuracy directly determines the forming quality of roadways.Methods Cantilever roadheaders involve nonlinear mechanical motion, hydraulic control, and cutting load, rendering it challenging to establish accurate control models. Using the philosophy of digital twin modeling, this study developed a method for optimizing the digital twin model of the mechanical-electro-hydraulic system of cantilever roadheaders based on virtual-physical consistency evaluation. Specifically, a digital twin model of the mechanical-electro-hydraulic system was developed using multi-domain co-simulation between AMESim and Simulink. This model allows …
Global Performance Of Remote Sensing-Based And Reanalysis-Driven Models To Estimate Open Water Evaporation, Júlia Brusso Rossi, Ayan Santos Fleischmann, Leonardo Laipelt, Bruno Comini De Andrade, Joshua B. Fisher, Justin L. Huntington, Christopher Pearson, R. Iestyn Woolway, Roseilson Vale, Júlio Tota, Gabriel B. Senay, Huilin Gao, Anderson Ruhoff
Global Performance Of Remote Sensing-Based And Reanalysis-Driven Models To Estimate Open Water Evaporation, Júlia Brusso Rossi, Ayan Santos Fleischmann, Leonardo Laipelt, Bruno Comini De Andrade, Joshua B. Fisher, Justin L. Huntington, Christopher Pearson, R. Iestyn Woolway, Roseilson Vale, Júlio Tota, Gabriel B. Senay, Huilin Gao, Anderson Ruhoff
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Evaporation plays an essential role in the water cycle, influencing local and regional climates while directly impacting water availability in lakes. However, directly measuring evaporation over water bodies remains challenging due to the high costs of installing and maintaining the required in situ instrumentation. Although several remote sensing algorithms have been providing evaporation estimates, the lack of a global validation hinders our understanding of their relative uncertainties and performances across different regions. Here, we analyze the performance of a suite of models that leverage satellite data and meteorological reanalysis to estimate evaporation over lakes worldwide. We compare 3 remote sensing‐based …
Paleoseismological Study Of The Active Faults Of Northern Cyprus, Hasan Elmaci, Şule Gürboğa, Seli̇m Özalp, Hasret Ozan Avci, Hakan Aydoğan, Ayhan Yavuzoğlu, Ali̇ Atalay Yüce, Meryem Kara, Ahmet Rasi̇mcan Öztürker
Paleoseismological Study Of The Active Faults Of Northern Cyprus, Hasan Elmaci, Şule Gürboğa, Seli̇m Özalp, Hasret Ozan Avci, Hakan Aydoğan, Ayhan Yavuzoğlu, Ali̇ Atalay Yüce, Meryem Kara, Ahmet Rasi̇mcan Öztürker
Turkish Journal of Earth Sciences
The tectonic framework of Northern Cyprus is presented in this study based on integrated fieldwork and paleoseismology. We identified multiple fault systems including the 214-km Dardere (Ovgos) Fault Zone (with seven segments), the Haspolat Transfer Fault, Mersinlik Fault, Yamaçköy Fault Zone, Boğazköy Fault, Alsancak Fault, and Geçitköy-Koruçam Fault Zone. Eleven paleoseismological trenches were excavated, with six yielding reliable results in terms of dating and stratigraphy. The results indicate recurrence intervals exceeding ~2500 years across different fault segments. The Dardere (Ovgos) Fault Zone shows the potential to generate earthquakes of up to Mw 7.80 with evidence of Holocene activity. The Haspolat …
Integrated Edge Detection Of Gravity Data And Seismicity Approach For Mapping Potential Faults In The Bolu Region, Hazel Deni̇z Toktay, Burçi̇n Di̇dem Tamtaş
Integrated Edge Detection Of Gravity Data And Seismicity Approach For Mapping Potential Faults In The Bolu Region, Hazel Deni̇z Toktay, Burçi̇n Di̇dem Tamtaş
Turkish Journal of Earth Sciences
The Bolu region, situated along the western–central segment of the North Anatolian Fault Zone (NAFZ), is characterized by a complex fault architecture in which multiple overlapping strike-slip segments and associated subsurface structures accommodate active crustal deformation. Although the principal fault strands of the NAFZ have been well mapped, several clusters of seismicity are observed in areas without clear surface fault expression, indicating the presence of subsurface or poorly expressed fault zones. In this study, we integrated edge detection methods with a seismicity approach to delineate active and buried structural features across the Bolu region. Bouguer gravity anomalies derived from the …
The Harmancık “Purple Jade”: A Unique Blueschist-Facies Metatrachyte With Significant Geoarchaeological Value, Gülteki̇n Topuz, Aral I. Okay, Constantinos Mavrogonatos, Osman Candan, Michael Brandl, Onur Bamyaci, Serap Ala Çeli̇k, Frederik Vingaard, Warren Thompson, Peter Christian Toft, Benjamin Dominguez Heredia, Tonny Bernt Thomsen, Lasse Vilien Sørensen
The Harmancık “Purple Jade”: A Unique Blueschist-Facies Metatrachyte With Significant Geoarchaeological Value, Gülteki̇n Topuz, Aral I. Okay, Constantinos Mavrogonatos, Osman Candan, Michael Brandl, Onur Bamyaci, Serap Ala Çeli̇k, Frederik Vingaard, Warren Thompson, Peter Christian Toft, Benjamin Dominguez Heredia, Tonny Bernt Thomsen, Lasse Vilien Sørensen
Turkish Journal of Earth Sciences
The so-called Harmancık “purple jade” from the Bursa region of northwestern Türkiye has attracted attention as a gemstone; however, its geological characteristics and provenance have long remained uncertain. This short communication presents new field observations along with mineralogical and petrological data concerning the provenance, metamorphic evolution, and geoarchaeological relevance of this unique rock type. The rock occurs as loose boulders scattered across cultivated fields in the villages of Akpınar, Kocapınar, and Gedikören, where it was previously interpreted either as part of Neogene sedimentary successions or as a high-pressure metamorphic rock affected by contact metamorphism. Our detailed mapping and field observations …
Toward The Significance Of Crevasse Orientation In Low And High Crevassed Regions On The Kennicott Glacier, Alaska, Usa, Claire A. Sturm
Toward The Significance Of Crevasse Orientation In Low And High Crevassed Regions On The Kennicott Glacier, Alaska, Usa, Claire A. Sturm
DePaul Discoveries
Supraglacial landforms serve as potential indicators of underlying bedrock morphology and glacier dynamics. The distribution and morphology of crevasses are closely associated with stress fields and ice-flow regimes, representing processes of stable glaciers, in contrast to their reduced occurrence in stagnant or receding ice masses. The orientation and density of crevasses influence a glacier’s ability to absorb solar energy, as they facilitate movement of meltwater down to subglacial rivers. Beyond the meltwater acting as a lubricant for basal sliding, the slope of the bedrock further impacts the local velocity and ice deformation of a glacier. The study of ice-fracturing mechanics …
Ecological Footprint Assessment, Santina Benincasa
Ecological Footprint Assessment, Santina Benincasa
Open Educational Resources
This handout guides students through a structured ecological footprint assessment using the online Footprint Calculator. By following a series of steps—selecting their location, entering detailed lifestyle information, and reviewing personalized results—students evaluate how many planets would be required if everyone lived with their same resource consumption patterns. The activity prompts learners to identify the largest contributors to their footprint, quantify their impact in global hectares, and explore scenario-based changes that could reduce their environmental demand. Through reflection, students consider how everyday human behaviors influence Earth’s productive capacity and resource availability. Overall, the exercise encourages critical thinking about sustainability and personal …
Observing System Simulation Experiments To Investigate Impacts Of Deep-Tropospheric Uas Flights On Forecasts, Kenneth Alexander Swan
Observing System Simulation Experiments To Investigate Impacts Of Deep-Tropospheric Uas Flights On Forecasts, Kenneth Alexander Swan
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
Uncrewed aircraft systems have emerged as a promising option to address meteorological gaps in observations in the lower troposphere. With recent advancements, UAS may be able to address gaps aloft in areas that lack coverage from radiosondes and commercial aircraft. UAS have shown the potential to significantly benefit NWP forecasts from profiles in the lowest 2 km AGL, but the impact of UAS profiles to the tropopause has yet to be quantified. Additionally, the impacts of hazardous flying conditions that UAS would encounter need to be addressed to guide future UAS capabilities. To address these questions, we designed an observing …
Elemental Analysis Of Upper Devonian To Lower Mississippian Organic-Rich Mudstone Cores From Kentucky By Portable X-Ray Fluorescence (Pxrf), Alex M. Washburn
Elemental Analysis Of Upper Devonian To Lower Mississippian Organic-Rich Mudstone Cores From Kentucky By Portable X-Ray Fluorescence (Pxrf), Alex M. Washburn
KGS Research Data Set
This dataset contains high-density portable X-ray fluorescence (pXRF) elemental analyses of 1,867 m (6,125 ft) of Upper Devonian to Lower Mississippian organic-rich mudstone cores from Kentucky. Analyses were collected from cores across the Illinois Basin, Cincinnati Arch, and Appalachian Basin to support regional evaluation of elemental variability, chemostratigraphy, and redox-sensitive trace-metal enrichment in Devonian–Mississippian mudstone successions. All measurements were conducted using a Bruker Tracer 5 pXRF analyzer with the factory “Mudrock Air” calibration, using analytical settings optimized for both low-atomic-number elements and transition metals/redox-sensitive trace elements. Reference materials SARM-41 and SGR-1 were analyzed throughout the analytical sequence to monitor instrument …
Synoptic Conditions Favoring Tropical Cyclone-Enhanced Southwest Monsoon High Precipitation Events In The Philippines, Alwin Andriel L. Bathan, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, John A. Manalo, Jun Matsumoto
Synoptic Conditions Favoring Tropical Cyclone-Enhanced Southwest Monsoon High Precipitation Events In The Philippines, Alwin Andriel L. Bathan, Lyndon Mark P. Olaguera, Faye Abigail T. Cruz, Jose Ramon T. Villarin, John A. Manalo, Jun Matsumoto
SOSE Affiliate: Manila Observatory
The interaction of tropical cyclones (TCs) with the southwest monsoon frequently causes heavy precipitation events (HPEs) and widespread flooding across the Philippines. Despite their substantial socio-economic impacts, the synoptic conditions that favor these events remain insufficiently understood, underscoring the need for systematic investigation to help improve forecasting and risk assessment. Lag composite analysis of daily rainfall records and reanalysis data from July to September for the period 1981–2023 shows that HPEs are more likely to occur when: (1) enhanced monsoon westerlies are present over the tropical Indian Ocean for at least nine days before the HPE, (2) a TC passes …
Block Kinematics, Interseismic Coupling And Fault Slip Rates In The Aegean Region From Gps And Earthquake Slip Vector Data: 1. Upper Plate Structures, Konstantinos Chousianitis, Sotiris Sboras, Volkan Özbey, Robert Mccaffrey, Semih Ergintav
Block Kinematics, Interseismic Coupling And Fault Slip Rates In The Aegean Region From Gps And Earthquake Slip Vector Data: 1. Upper Plate Structures, Konstantinos Chousianitis, Sotiris Sboras, Volkan Özbey, Robert Mccaffrey, Semih Ergintav
Geology Faculty Publications and Presentations
We represent the active deformation of the Aegean region with an elastic‐kinematic block model composed of a finite number of rotating crustal blocks whose boundaries coincide with major active structures. A total of 832 GPS velocities and 146 earthquake slip vectors were inverted to provide estimates of block rotations and interseismic locking on block‐bounding faults so as to best reproduce the observed deformation field. Our regional model allowed us to derive a self‐consistent set of geodetic slip rates for upper plate faults and the Hellenic subduction system, the results of which are presented in a companion paper, and to determine …
Soil Moisture Regime Effects On Greenhouse Gas Emissions In A Native Tallgrass Prairie In The Ozark Highlands, Thomas William Dockery
Soil Moisture Regime Effects On Greenhouse Gas Emissions In A Native Tallgrass Prairie In The Ozark Highlands, Thomas William Dockery
Graduate Theses and Dissertations
The Ozark Highlands is an ecoregion in the mid-southern portion of the United States that is characterized by a mosaic of tallgrass prairies, oak (Quercus spp.) savannas, and oak-hickory (Carya spp.) forests, which represents a unique biophysical transition zone between the relatively dry grasslands of the west and the humid forests of the southeast. Quantifying greenhouse gas (GHG) emissions, namely carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), from natural, undisturbed ecosystems is critical to understanding atmospheric warming and climate-change implications. The objective of this study was to simultaneously evaluate CO2, CH4, and N2O emissions in an aquic and …
Hydroclimatic Whiplash Across The Contiguous United States: Characterizing Wet–Dry Transitions In Pdsi And Phdi, James Lam, Thomas Christopher Piechota
Hydroclimatic Whiplash Across The Contiguous United States: Characterizing Wet–Dry Transitions In Pdsi And Phdi, James Lam, Thomas Christopher Piechota
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Hydroclimatic whiplash, characterized by rapid transitions between wet and dry conditions, poses a growing challenge for water resource management and ecosystem stability. However, the spatial and statistical characteristics of wet–dry transitions across the contiguous United States are not fully understood. This study analyzed Palmer Drought Severity Index (PDSI) and Palmer Hydrological Drought Index (PHDI) records from 344 NOAA climate divisions spanning 1895–2024. Whiplash was defined as a transition between severe drought and severe wetness within 12-month rolling windows. Statistical descriptors including lag-1 autocorrelation, variance, and skewness were evaluated for whiplash and non-whiplash windows to assess differences between them. Whiplash hotspots …
Instructions To Authors, Academy Editors
Instructions To Authors, Academy Editors
Journal of the Arkansas Academy of Science
No abstract provided.