Physical Sciences and Mathematics Commons^™

The Evaluation Of Roughages Under The Gdr Feed Evalua­Tion System, Reinhard Schiemann

IGC Proceedings (1977-2023)

The purpose and content of the GDR Feed Evaluation System are discussed in the form of a summary report. The GDR Feed Eval­uation System incorporates, in a form suitable for practical application, the following:

Parameters and methods for the complex evaluation of feeds with particular refer­ence to energy and protein (including amino acids), prepared in the form of detailed feed tables for feeding and planning pur­poses [9, 10];

Parameters and methods for determining daily feed requirements and application rates, in the fonn of energy and nutrient • requirement standards for composing op­timum rations according to animal species and performance (9, …

Environmental Dna For Endangered Freshwater Mussel Monitoring: A Review On Global Synthesis Of Edna Methods, Challenges, And Innovative Strategies, Mizanur Rahman, Md. Saydur Rahman, Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Freshwater mussels (family Unionidae) are among the most endangered aquatic species worldwide, making effective monitoring vital for their conservation. Traditional surveys are laborious, time-consuming, and often miss rare or low-density populations. Environmental DNA (eDNA) is a highly sensitive, non-invasive approach for freshwater mussel detection and monitoring; however, uncertainties in ecological interpretation continue to limit its broader application in freshwater biodiversity monitoring. We conducted a systematic review of 49 peer-reviewed studies, identified through an extensive literature search, to assess temporal research trends, methodological advancements, ecological contexts, and regulatory readiness of freshwater mussel eDNA monitoring. Findings show that freshwater mussel eDNA research …

Mining Legacy And Wildfires: Interfacial Reactions Affecting Metal Mobility, Eresay Alcantar-Velasquez

Earth and Planetary Sciences ETDs

We identified water labile interfacial reactions between laboratory burned pinewood ash and mine waste solids that influence metal mobilization. The Upper Gallinas Creek Watershed in New Mexico is affected by wildfires and mining legacy. Pinewood and mine waste sediments were sampled from the area, and the pinewood was burned at 350°C to simulate medium burn intensity ignition. Rapid desorption and gradual dissolution of Mn and Fe was detected by ICP-MS as pH decreased over time. After reacting 18 MΩ ultra-pure water with a mixture of pinewood ash and mine waste sediments Fe (143%) and Mn (89.2%) concentrations increased over time. …

Mapping Along-Strike Changes In Shallow Subduction Zone Geometry At The Alaska Subduction Zone Using Seismic Reflection And Tectono-Geomorphic Analysis, Madelyn K. Hurd

Earth and Planetary Sciences ETDs

The Alaska subduction zone, where the oceanic Pacific plate subducts beneath the continental North American plate at a rate of 60-66 mm/yr, has hosted more >M8 earthquakes over the last century than any other subduction zone globally. The largest of these, the 1964 M9.2 Alaska earthquake, ruptured 800 km of the margin, including a high slip patch near the trench offshore Kodiak Island. The 1964 rupture area may have overlapped with the 1938 M8.3 Semidi earthquake rupture zone that lies to the west. Slip propagation near the subduction trench during large earthquakes can control tsunamigenesis, and differences in wedge geometry …

Information Theory Analysis Of Water Vapor Stable Isotopes From The Sail Campaign, Matthew John Rybecky

Earth and Planetary Sciences ETDs

Understanding the processes that control water vapor isotopic composition in mountain environ- ments is essential for interpreting isotope records and predicting water resource responses to cli- mate change. This thesis applies information theory to continuous, high-resolution water vapor stable isotope measurements from the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign in the East River watershed of Colorado’s Upper Gunnison Basin, spanning the winter- to-spring transition of 2022–2023. The analysis employs Shannon entropy, mutual information, transfer entropy, and joint transfer en- tropy (JTE) to quantify how environmental variables, including surface meteorology, radiation, tur- bulent fluxes, and ERA5 reanalysis products, transfer information …

Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby

Civil Engineering ETDs

Wildfires alter the water quantity and quality in downstream river networks. Fires promote biodiversity, maintain habitat, and provide many ecosystem services in a fire-adapted landscape. However, changes in the natural fire regimes can alter ecosystem function and threaten the water security of impacted downstream communities. The magnitude, timing, and persistence of these impacts are difficult to predict due to the lack of high-resolution datasets with adequate coverage to evaluate spatiotemporal trends after a fire. This dissertation moves us beyond the status quo to evaluate post-fire fluvial responses across scales, from the event-scale impacts after the Hermit’s Peak-Calf Canyon wildfire in …

Reading The Martian Surface: Impact Crater Distributions And Geochemical Signatures In Gale Crater As Recorded By The Curiosity Rover, Megan E. Hoffman

Earth and Planetary Sciences ETDs

The Curiosity rover has been exploring Gale crater, a large impact basin near the Mars equator since 2012. This mission has greatly improved our ability to explore the surface of Mars with a suite of geologic tools and cameras and has revealed that Mars likely once resembled present-day Earth. In this dissertation, I utilize measurements and data taken by Curiosity to analyze the distribution and preservation of small impact craters at meter scales, I quantify the formation characteristics of a small impact crater cluster, and I examine the presence of barium in a geologic unit with high-Si to constrain sediment …

Pebble Accretion: Compositions And Water Origins Of Terrestrial Planets, Susmita Garai

Earth and Planetary Sciences ETDs

Two leading models of planet formation invoke either stochastic collisions among km-sized planetesimals, or pebble accretion of sub-mm-cm solids regulated by gas drag. While collision based models typically require tens to hundreds of millions of years to assemble terrestrial planets, pebble accretion can produce Mars to Jupiter-mass bodies within the lifetime of the protoplanetary disk. Although widely accepted for the rapid growth of giant planet cores, the role of pebble accretion in forming terrestrial planets, including Earth, remains debated. Here, we investigate the consequences of pebble accretion for Earth’s origin. Here, I combine numerical models and laboratory experiments to find …

Exploring The Role Of A Mushy, Crustal Compliant Region In Volcano Deformation, Grant A. Block

Physics & Astronomy ETDs

Volcanoes are both creative and destructive forces that have shaped and continue to shape our world from early geologic time to the present day. Continued study of volcanic processes not only better prepares us for monitoring volcanic hazards but also allows us to better understand processes fundamental to Earth as we know it, such as the generation of the atmosphere and accretion of the continents. This dissertation focuses on an integral part of volcanic processes: the trans-crustal magmatic transport system. Specifically, we investigate regions of these transport systems where magma pools in melt-rich lenses within broader regions of low melt-fraction, …

Hydrus Modeling Of A Sahelian Agroforestry System: An Investigation Of Local Water Balance, Nicole A. Butler

Master's Theses

Effects of drought can devastate agricultural productivity in the West African Sahel. Climate complexities, such as lower-than-average rainfall and high winds, can lead to crop failure and low yields, thereby creating food security issues. Agriculture in the Sahel is primarily rainfed, and the rain is becoming increasingly unpredictable due to the changing climate. The method of intercropping groundnut (Arachis hypogea) and pearl millet (Pennisetum glaucum) with the shrub species Piliostigma reticulatum can combat the effects of climate change and restore degraded soil. Intercropping can increase water availability and crop yield when compared to crops grown in the absence of shrubs. …

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 …

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

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 …

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 …

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

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

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

Coal Geology & Exploration

No abstract provided.

History, Current Status, And Implications Of The Exploration And Exploitation Of Coal Resources In Guangxi, China, Wang Hui, Han Xiaozhong, Peng Zhilong, Li Huoying, Qin Baojian, Lu Ankang, Qin Xiaoyan, Peng Feifei, Xu Huiheng, Lan Bingui

Coal Geology & Exploration

Objective Based on a comprehensive review of the history and current status of coal exploration and exploitation, this study presents an analysis of both the endowment characteristics and the exploration and research levels of coal resources in Guangxi Zhuang Autonomous Region. From the perspective of coal self-sufficiency capacity and energy security guarantee, this study proposes several recommendations for the exploration and exploitation of coal resources in the region. Methods The exploration level, current status of exploitation, and supply-demand imbalance of coal resources in Guangxi are determined through a systematic literature review, surveys of coal mine enterprises, and exchanges with relevant …

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 …

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 …

Research And Practice Of Four-Dimensional In-Situ Stress Fields For Deep Coalbed Methane Production: A Case Study Of The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Chen Yiyu, Gao Deli, Zhao Haifeng, Chen Gaojie

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs are characterized by well-developed microstructures and natural fractures, along with highly heterogeneous rock mechanical properties and in-situ stress field distribution. The CBM production of the reservoirs tends to cause constantly evolving formation pressure and in-situ stress within the control ranges of CBM wells, further enhancing the complexity of stress distribution. Additionally, severe fracturing channeling can be observed between new and old wells. This phenomenon is primarily triggered by in-situ stress variations induced by large-scale fracturing and CBM production. Therefore, accurately assessing the dynamic evolutionary patterns of in-situ stresses in reservoirs after fracturing and during …

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, …

Enrichment Mechanisms Of U And Th Elements In The Bauxite Rock Series Of The Benxi Formation, Lower Carboniferous, Central North China Block, Bian Yukang, Zhang Xiaoyang, Chen Jinfeng, Lyu Dawei, Zhu Dongya, Liu Quanyou, Meng Qingqiang, Shen Xiaoli, Li Qing, Kong Weijiang, Dou Yunfei

Coal Geology & Exploration

Objective Uranium (U) and thorium (Th) in rocks and minerals are the material basis for the generation and release of crust-derived helium. Methods The enrichment characteristics and mechanisms of U and Th are key to understanding the accumulation of crust-derived helium reservoirs. Taking the bauxite series of the Benxi Formation in the central North China Block as the research object, this study reveals the enrichment mechanisms of U and Th in the bauxite series and calculates the helium generation rate by means of petrogeochemical and chronological research methods, combined with detrital zircon dating, sedimentary environment identification, and mass balance calculation. …

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 …

Sand Tank Experiments On The Seepage And Water Pressure Distribution During Single-Well Dewatering At The Bottom Of A Confined Aquifer, Wang Wenxue, Zhang Mengying, Li Yang, Fang Yuan, Zhao Shuli, Shen Mengjun

Coal Geology & Exploration

Background Depressurization through dewatering using inclined wells arranged at the aquifer bottom represents a crucial technical approach to the prevention and control of water-sand inrush disasters during coal mining beneath aquifers. However, the mechanisms underlying seepage-pressure interactions and water-preserved depressurization remain poorly understood. Methods Based on the water-yield properties of confined aquifers and the distribution characteristics of inclined wells for dewatering, this study developed a fan-shaped sand tank experimental system for simulating dewatering and seepage from confined aquifers. Using the experimental system, this study carried out seepage experiments using a partially penetrating well at the bottom of a confined aquifer …

Load Sharing Patterns And Their Key Influencing Factors For The Composite Structure Of A Lined Hard Rock Cavern For Compressed Air Energy Storage, Hu Lihua, Zhou Qiming, Zhang Kai, Yu Liyuan, Liang Xin, Sun Qiang, Wu Yun, Hu Chengguo, Li Wei

Coal Geology & Exploration

Objective Compressed air energy storage (CAES) in a lined hard rock cavern holds great prospects. However, the load sharing mechanisms of the cavern’s composite structure, comprising a sealing layer, lining, and surrounding rocks, remain poorly understood.Methods Based on the elastic analytical solutions of stress fields, this first study derived the radial load equilibrium equations for the composite structure of a lined hard rock cavern for CAES. Accordingly, a novel method for calculating the load sharing ratios of the composite structure was developed. Then, an analysis scheme for the load sharing ratios was designed. Using this scheme, this study investigated …

Cnn-Based Assessment Of The Degrees Of Fracture Development In Bedrocks And Classification Of Bedrock Weathering Zones, Lei Jian, Lu Haifeng, Fan Yufei

Coal Geology & Exploration

Background Bedrock weathering zones exhibit distinct vertical gradational characteristics. Accurately identifying the degrees of fracture development in the zones is critical to the safe production of mines in shallowly buried coal seams covered by thick water-bearing unconsolidated layers. Methods Focusing on the Qinan coal mine in Anhui Province, this study proposed a hybrid convolutional neural network (CNN) model, which enabled feature extraction using a synergistic architecture consisting of conventional convolutional layers and inception modules. Specifically, based on conventional log data and calculated shale content and fracture development index, combined with core observations, this study constructed a dataset containing labels that …

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

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 …