Earth Sciences Commons^™

Positioning Error Compensation Of Drilling Robot Arm For Coal Mine, Liang Chunmiao, Yao Ningping, Yao Yafeng, Peng Tao

Coal Geology & Exploration

At present, the pose of drilling robots is mostly adjusted by manual remote control and manual retest in combination. Full automatic adjustment has not been achieved. Besides, due to the low precision of open-loop control and inadequate automation capability, the accurate hole positioning and automatic construction of hole groups cannot be realized by drilling robots with water exploration and discharge, outburst prevention and punching prevention in coal mines. Herein, the kinematic model of drilling arm was established by analyzing the structure and action of the drilling robot’s drilling arm. Meanwhile, the dip angle factors such as machining error, body deformation …

Operation Process Identification For Intelligent Drill Rig Base On Analytic Hierarchy Process, Zhu Qianxiang, Luo Pengping, Wang Longpeng, Xing Wang, Wang Tianlong

Coal Geology & Exploration

It is very difficult to automatically identify the current process during the intelligent construction of coal mine drill rigs. In response to this, an operation process identification method was proposed, which includes hierarchical modeling of drill rig operation and probability inference of process execution. Firstly, the coupling process among the components of different granularity during the operation of drill rig is described and modeled based on the hierarchical analysis method, which reveals the interactive characteristics between equipment, function and system during the execution of each process. Secondly, Bayesian probabilistic reasoning method is introduced based on the above research to establish …

A Method For Coal Seam Pressure Relief Based On Steel Cone Impact, Ren Zhimin, Lyu Mengjiao, Wang Fei, Wang Yu, Zhang Guangtai

Coal Geology & Exploration

This study aims to solve the mining safety problems caused by rock bursts in coal mines. With the geological mining conditions of the No.3 coal seam in the Wulihou coal mine in Zuoquan County, Jinzhong City, Shanxi Province as the engineering background, this study proposed a method for coal seam pressure relief based on steel cone impact. Specifically, based on the electromagnetic repulsion generated between energized coils, this study derived the functions of impact force produced when a magnetically driven coil-wound steel cone impacted the coal seam. Combining the theory on elastic mechanics, this study analyzed the stress field distribution, …

Two-Phase Flow Chokeling Results And Control In High-Pressure Gas Wells Producing Water, Liu Xinfu, Liu Chunhua, Li Qingping, Yao Haiyuan, Hao Zhongxian, Liu Yongfei

Coal Geology & Exploration

Prediction and control of two-phase flow chokeling in tight gas wellbores are essential for the normal operation and hydrate control of high-pressure gas wells producing water. The thermodynamic differential equations of energy, kinetic energy and temperature and models of chokeling field for two-phase energy, system heat, mass balance and flow were developed under the conditions of isentropic adiabatic, isobaric heat capacity, constant volume heat capacity, and chokeling energy. A methodology on predicting characteristics and control of two-phase flow before and after chokeling was proposed for gas-water two phase flow. It provided a theoretical basis for optimizing the structural parameters of …

High-Accuracy Reconstruction Of Missing Ground-Penetrating Radar Signals Based On Projection Onto Convex Sets In The Curvelet Domain, Wu Qiming, Wang Honghua, Xi Yuhe, Wang Yucheng

Coal Geology & Exploration

Influence by the acquisition environments and instrument performance, missing signals and destructed channels are inevitable in measured ground-penetrating radar (GPR) profiles. They can cause event discontinuity of reflected and diffracted waves generated by targets, severely impairing the accuracy and resolution of subsequent processing and imaging. Hence, by combining the projection onto convex sets (POCS) algorithm extensively used in image processing with the curvelet transform exhibiting high sparsity, this study proposed a high-accuracy reconstruction method for missing GPR signals based on curvelet-domain POCS. Building on the compressive sensing theory, the objective function for missing signal reconstruction based on discrete curvelet transform …

Favorable Factors In Methane Production From Residual Coal Post-Biohydrogen Generation, Xia Daping, Liao Jiajia, Chen Zhenhong, Chen Xi, Guo Hongyu, Huang Dan

Coal Geology & Exploration

Determining favorable factors in methane production from residual coal post-biohydrogen production holds great theoretical and practical significance for improving the efficiency of methane production in the second stage of coal-based poly-generation. This study focuses on residual coal after hydrogen generation through anaerobic fermentation. Using coal samples from the Baiyinhua open-pit mine in Inner Mongolia as fermentation substrates, this study explored the dynamic trends of both the methane production and structure of the residual coal under different conditions by altering the aeration conditions and hydraulic retention time (HRT). Key findings are as follows: (1) Among the experiment groups with different atmosphere …

Numerical Simulation On Influence Of Skin Effect On Groundwater Flow Velocity In Wellbore, Wang Qihang, Li Xu, Guo Qiang, Kuai Dawei

Coal Geology & Exploration

Groundwater flow velocity in wellbore is usually measured by single-well tracking tests or Aqua Vision flow velocity and direction meters to calculate the groundwater flow velocity in the aquifer. Due to the impact of the skin structure, the groundwater flow field near the wellbore changes, causing a difference between the flow velocity in the wellbore and that in the aquifer. In order to investigate the influence of the skin effect on the groundwater flow velocity in the wellbore, a numerical model of groundwater flow that considers the skin effect was established using the COMSOL Multiphysics software. On this basis, the …

Leveraging Systems Thinking For Global Environmental Health, Martha M. Mcalister

USF Tampa Graduate Theses and Dissertations

Environmental health inequities such as household air pollution, inadequate water, sanitation, and hygiene, and chemical pollution persist globally and have myriad consequences on individual and societal well-being. Unfortunately, while billions of dollars and countless hours of research have been applied towards addressing these issues in development, humanitarian, and environmental justice contexts, attempts to reduce the environmental burden of disease can seem successful at first, but then backslide to pre-intervention conditions (or worse). This is indicative of policy resistance, a tendency of complex systems that makes it very difficult to enact change if the “rules” of the system are misunderstood. There …

Comparative Life Cycle Assessment Of Copper Production, Xiaohan Wu

Graduate Industrial Research Symposium

Copper demand will surge significantly in the context of global renewable energy technology implementation, but its production is an energy-intensive process. It is crucial to choose the best production method to reduce environmental damage in terms of the enormous copper supply. This research develops a multi-criteria life cycle assessment model for the three main copper production routes- pyrometallurgy, hydrometallurgy, and bioleaching. We complied material and energy flow data to assess each route's life cycle greenhouse gas (GHG) emissions, cost, and resource efficiency. Results indicate bioleaching emits the least GHG emissions (4.09 kg-CO2 eq/kg copper) among the three routes. Hydrometallurgy is …

Spatial Distribution And Movement Of Atlantic Tarpon (Megalops Atlanticus) In The Northern Gulf Of Mexico, Shane A. Stephens, Michael A. Dance, Michelle Zapp Sluis, Richard J. Kline, Matthew K. Streich, Gregory R. Stunz, Aaron J. Adams, R. J. David Wells, Jay R. Rooker

School of Earth, Environmental, & Marine Sciences Faculty Publications

Atlantic tarpon (Megalops atlanticus) are capable of long-distance migrations (hundreds of kilometers) but also exhibit resident behaviors in estuarine and coastal habitats. The aim of this study was to characterize the spatial distribution of juvenile tarpon and identify migration pathways of adult tarpon in the northern Gulf of Mexico. Spatial distribution of juvenile tarpon was investigated using gillnet data collected by Texas Parks and Wildlife Department (TPWD) over the past four decades. Generalized additive models (GAMs) indicated that salinity and water temperature played a significant role in tarpon presence, with tarpon occurrences peaking in the fall and increasing …

Publications And Other Works By R. F. Diffendal, Jr., Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

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Updated March 2024

Human-Wildlife Conflict And The Likelihood Of Reporting Losses In Nepal, Gita Bhushal, Bernabas Wolde, Pankaj Lal

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

All development indices are changing due to increased exploitation of nature and growing economies in developing countries. This situation may increase the intensity of conflict between humans and wild species, such as large carnivores. Despite the increasing intensity of human-wildlife conflicts and the existing compensation scheme that compensates for the loss, most losses to human-wildlife conflicts are not reported to authorities. Thus, this study was conducted in the Banke National Park of Nepal to explore possible factors influencing the propensity to report losses. All 197 surveyed participants reported suffering from crop raids by wild animals, and 80 respondents (40.60 %) …

Pcor Partnership Atlas, Wesley D. Peck, Kari Suedel, Kyle A. Glazewski, Kevin C. Connors, James A. Sorensen, Charles D. Gorecki, Brian P. Kalk, John A. Harju

EERC Maps and Infographics

The Plains CO₂ Reduction (PCOR) Partnership Atlas provides a profile of CO₂ sources and potential storage locations across the PCOR Partnership region. The revised sixth edition of the Atlas provides an up-to-date look at PCOR Partnership initiative activities, including additional regional characterization and updates on commercial projects. Additional background information on carbon capture, utilization, and storage (CCUS) is included to give a better understanding of how CCUS addresses concerns about climate change while allowing future energy needs to be met.

An Examination Of Thematic Research, Development, And Trends In Remote Sensing Applied To Conservation Agriculture, Zobaer Ahmed, Aaron Shew, Lawton Nalley, Michael Popp, V. Steven Green, Kristofor Brye

Center for Advanced Spatial Technologies Publications and Presentations

Conservation agriculture seeks to reduce environmental degradation through sustainable management of agricultural land. Since the 1990s, agricultural research has been conducted using remote sensing technologies; however, few previous reviews have been conducted focused on different conservation management practices. Most of the previous literature has focused on the application of remote sensing in agriculture without focusing exclusively on conservation practices, with some only providing a narrative review, others using biophysical remote sensing for quantitative estimates of the bio-geo-chemical-physical properties of soils and crops, and few others focused on single agricultural management practices. This paper used the preferred reporting items for systematic …

Exploitation Of Environmental Dna (Edna) For Ecotoxicological Research: A Critical Review On Edna Metabarcoding In Assessing Marine Pollution, Sakib Tahmid Rishan, Richard Kline, Md Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Highlights

• eDNA describes the genetic material of organisms present in aquatic environments.

• eDNA metabarcoding characterizes DNA of various marine species from a single sample.

• eDNA has enormous promise for ecotoxicological research in marine environments.

Abstract

The rise in worldwide population has led to a noticeable spike in the production, consumption, and transportation of energy and food, contributing to elevated environmental pollution. Marine pollution is a significant global environmental issue with ongoing challenges, including plastic waste, oil spills, chemical pollutants, and nutrient runoff, threatening marine ecosystems, biodiversity, and human health. Pollution detection and assessment are crucial to understanding the state of …

Predictive Understanding Of Lake Water Temperature And Dissolved Oxygen Profiles Across The Red River Basin Through Interpretable Machine Learning, Isabela Suaza Sierra

Open Access Theses & Dissertations

Accurately predicting lake water temperature (LWT) and dissolved oxygen (DO) is crucial for determining threshold values of fish survivability under warmer global conditions, with recreational fishing in reservoirs significantly contributing to regional economies, such as $779 million and $1,891 million annually to the economies of Oklahoma and Texas, respectively. Current mathematical models for temperature and oxygen profiles, which incorporate multi-layer and turbulent mixing equations, are complex and challenging to parameterize, particularly due to uncertainties in acquiring sufficient data for training and validation. Leveraging the flexibility and information extraction power of machine learning (ML) methods, this master thesis aimed to set …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Deep Coalbed Methane Production Technology For The Eastern Margin Of The Ordos Basin: Advances And Their Implications, Zeng Wenting, Xu Fengyin, Zhang Lei, Sun Weiwei, Wang Qian, Liu Yinhua, Yu Lizhu, Ji Liang, Zeng Quanshu, Zhang Kang

Coal Geology & Exploration

Contrasting with shallow to moderately deep coalbed methane (CBM) reservoirs, deep CBM reservoirs exhibit favorable coal structures, high formation pressure, high free gas ratios, and high contents of total dissolved solids (TDS) and CO₂. Extensive fracturing allows for CBM flowing at the initial stage, while the production parameters vary significantly throughout the CBM production. This requires wide technological boundaries of the main production technologies. Compared to shale gas and tight gas, deep CBM manifests different production mechanisms and relatively low free gas ratios, which lead to short flowing cycles of CBM. This necessitates timely water withdrawal for CBM …

Differences In Geological Conditions Of Deep And Shallow Coalbed Methane And Their Formation Mechanisms, Xu Hao, Tang Dazhen, Tao Shu, Li Song, Tang Shuling, Chen Shida, Zong Peng, Dong Yu

Coal Geology & Exploration

Deep coalbed methane (CBM) boasts abundant resources and great potential for exploitation. However, there is a lack of in-depth studies on the internal connections between deep and shallow CBM. This study investigated the Upper Paleozoic coalbed in the Ordos Basin. From the perspective of coalbed formation and evolution, it obtained three burial depth evolution modes of coalbed through summaries: both the maximum and present burial depths exceeding 2000 m, the maximum burial depth over 2000 m while the present burial depth less than 2000 m, and both the maximum and present burial depths less than 2000 m. This study systematically …

Occurrence Mechanism, Environment And Dynamic Evolution Of Gas And Water In Deep Coal Seams, Li Yong, Xu Lifu, Liu Yu, Wang Ziwei, Gao Shuang, Ren Ci

Coal Geology & Exploration

Accurately understanding of the occurrence states, relative content, and distribution characteristics of gas - water under deep conditions has important guiding significance for efficient exploration and development of coalbed methane (CBM). Based on the theoretical model, molecular simulation and systematic analysis of gas-water, the occurrence states of gas-water in coal seam is clarified, and the boundary and dynamic evolution process of gas-water dynamic migration and accumulation are revealed. Considering the coal - water interface interaction, the mobility and occurrence states of water, the coalbed water can be divided into movable water (gravity water and capillary water), bound water (adsorbed water, …

Effects Of Depth On Gas-Bearing Properties Of Coal Reservoirs And Their Coupling Relationships With Coalbed Methane Accumulation, Chen Shida, Hou Wei, Tang Dazhen, Li Xiang, Xu Hao, Tao Shu, Li Song, Tang Shuling

Coal Geology & Exploration

Burial depth serves as a comprehensive factor influencing coalbed methane (CBM) accumulation. Understanding the effects of depth on gas-bearing properties is critical for ascertaining the occurrence states and accumulation mechanisms of deep/shallow CBM. Based on the present situation of CBM exploration and the dissection of data from CBM exploration wells on the eastern margin of the Ordos Basin, this study explored the effects of burial depth on the gas content, saturated adsorbed gas capacity, and gas saturation of coal seams, as well as their coupling relationship with accumulation processes, using conventional and unconventional petroleum accumulation. The results indicate that CBM …

Deep Coalbed Methane Resources In The Shenmu-Jiaxian Block, Ordos Basin, China: Geological Characteristics And Potential For Exploration And Exploitation, Li Guoyong, Yao Yanbin, Wang Hui, Meng Lingjian, Li Peijie, Zhang Yongchao, Wang Jianwei, Ma Limin

Coal Geology & Exploration

China boasts abundant coalbed methane (CBM) resources in deep layers (burial depths: greater than 2000 m), with considerable potential for CBM exploration and development. Compared to medium and shallow CBM, deep CBM differs significantly in enrichment and accumulation patterns and exploitation means. Therefore, there is an urgent need to dissect key CBM blocks. The Shenmu-Jiaxian block, situated in the northeastern Ordos Basin, is currently in the early stages of deep CBM exploration, with enrichment characteristics and exploration potential remaining undefined. Based on recently obtained seismic data, logging data from over 300 wells, and analytical results from four cored wells, this …

Potential For The Production Of Deep To Ultradeep Coalbed Methane Resources In The Upper Permian Longtan Formation, Sichuan Basin, Ming Ying, Sun Haofei, Tang Dazhen, Xu Liang, Zhang Benjian, Chen Xiao, Xu Chang, Wang Jiaxian, Chen Shida

Coal Geology & Exploration

Breakthroughs have been achieved in the high-yield gas flow of coalbed methane (CBM) wells with burial depths ranging from 1000 to 2500 m in the Cainan area of the Junggar Basin and the Daning-Jixian and southern Yanchuan blocks on the eastern margin of the Ordos Basin, signifying the enormous potential for the production of deep CBM. In the Sichuan Basin, the thin to moderately thick coal seam groups (7‒15 layers) in the Upper Permian Longtan Formation primarily exhibit burial depths ranging between 2000 and 4500 m. In the central Sichuan Basin, characterized by north-dipping monoclines and local low-amplitude uplifts, deep …

Geological Characteristics And Favorable Area Evaluation Of Deep Coalbed Methane In Wangfu Fault Depression, Southern Songliao Basin, Shen Xia, Gong Haitao, Shao Mingli, Yang Minfang, Huo Wanguo

Coal Geology & Exploration

The Wangfu fault depression in the southern Songliao Basin is rich in coalbed methane (CBM) resources. However, CBM exploration in this area has been restricted by the low-level exploration of deep CBM and a lack of systematic studies on the geological characteristics of CBM, primary factors controlling CBM enrichment and accumulation, and the selection of favorable targets. Therefore, based on the systematical analysis of the geological characteristics of coal-bearing strata, this study identified the major factors controlling deep CBM accumulation, established the index system for favorable area selection, and predicted the favorable areas of CBM enrichment. The results show that: …

Moderately Deep Coalbed Methane Reservoirs In The Southern Qinshui Basin: Characteristics And Technical Strategies For Exploitation, Zhang Cong, Li Mengxi, Hu Qiujia, Jia Huimin, Li Kexin, Wang Qi, Yang Ruiqiang

Coal Geology & Exploration

This study investigated the northern Zhengzhuang-western Qinnan block for the purpose of achieving effective exploitation of moderately deep coalbed methane (CBM) reservoirs in the southern Qinshui Basin. Based on results from the analyses and tests of parametric wells, including core analysis and tests, injection/falloff tests, and in situ stress cyclic tests, as well as a large amount of dynamic and static data, this study expounded on the characteristics of moderately deep CBM reservoirs in the study area by comparison with shallow counterparts. Then, it explored the technical improvements in fracturing through vertical wells and staged fracturing through horizontal wells for …

A Calculation Model Of Free Gas Saturation In Deep Coalbed Methane Reservoirs And Its Application, Shi Juntai, Cao Jingtian, Xu Fengyin, Xiong Xianyue, Huang Hongxing, Sun Zheng, Jia Yanran, Ma Shurui, Zheng Haohang, Deng Ting, Li Jing, Li Xiangfang

Coal Geology & Exploration

In recent years, breakthroughs have been achieved in the exploration of deep coalbed methane (CBM) in China based on fine-scale geological research and techniques such as multistage hydraulic fracturing using proppants in a horizontal well. As a result, some wells yielded daily gas production of up to 100000 m³, inspiring confidence again in the CBM industry. However, since deep coal reservoirs occur in a complex geological environment characterized by high in-situ stress, high geotemperature, high pore pressure, and low permeability, there is an urgent need to reveal the typical parameters of coal reservoirs at different depths and the …

Mechanisms And Technological Parameter Optimization Of Near-Wellbore Laser Thermal Fracturing For Deep Coal Seams, Zhao Haifeng, Yang Ziyi, Liang Wei, Zhong Junbing

Coal Geology & Exploration

China boasts abundant deep coalbed methane (CBM) resources, which play a significant role in further CBM production. However, deep coal seams exhibit low porosities and ultra-low permeabilities due to intricate geological conditions. In the drilling process, drilling fluids enter the reservoirs, prone to cause near-wellbore contamination. Although conventional hydraulic fracturing technology tends to create fractures in the direction of the maximum horizontal principal stress, it is challenging for this technology to achieve blockage removing throughout the whole borehole. Laser thermal fracturing technology can break rocks in a short time. Furthermore, it allows for the laser irradiation angle to change freely …

Exploring The Principle And Method For Commingled Production Of Coal-Measure Gas Through Layered Pressure Relief In Surface Wells, Li Rui, Jin Lihong, Xia Binwei, Ge Zhaolong

Coal Geology & Exploration

This study aims to gain an in-depth understanding of factors restricting the commingled production of coal-measure gas and boost the contributions of various pay zones to gas production. To this end, it analyzed the essential factors of the dynamic, channel, and gas source conditions in the commingled production. The dynamic conditions for the commingled exploitation of multiple reservoirs can be met by (1) enhancing the flow conductivity of reservoirs by altering the crustal stress state and (2) changing reservoir fluid pressure by layers. Following this principle, this study proposed a method for the commingled production of coal-measure gas through layered …

Underground Coal Gasification: Overview Of Field Tests And Suggestions For Industrialization, Dong Zhen, Chen Yanpeng, Kong Lingfeng, Wang Feng, Chen Hao, Xue Junjie, Zhang Mengyuan, Chen Shanshan, Zhao Yufeng, Yu Yueyu, Gong Wanxing, Sun Hongliang, Wang Xinggang

Coal Geology & Exploration

Driven by the dual demands for achieving the goals of peak carbon dioxide emissions and carbon neutrality and for ensuring national energy security, underground coal gasification (UCG) in China is embracing a new historical development opportunity. To scientifically formulate a route for making technological breakthroughs in UCG and accelerate its industrialization, this study analyzed the history of UCG field tests, dividing UCG into three stages: UCG based on coal mines, vertical/directional wells, and horizontal wells. By exploring the underlying logic that propelled innovations in UCG technologies in different stages, this study delved into the technical and non-technical reasons for the …

Deep Coal Reservoirs In The Ningwu Basin: Geothermal Field Characteristics And Their Effects On Gas-Bearing Properties, Xi Zhaodong, Tang Shuheng, Liu Zhong, Qu Xiaorong, Zhang Pengbao, Su Yufei, Zhang Qian

Coal Geology & Exploration

Temperature acts as an important factor affecting the gas-bearing properties of deep coal reservoirs, further affecting the development performance of deep coalbed methane (CBM). Therefore, ascertaining the geothermal conditions of coal reservoirs and their effects on the gas-bearing properties of deep coal reservoirs is critical to the systemic understanding of the enrichment characteristics and production patterns of deep CBM. For coal seam No.9 in the Taiyuan Formation within the Ningwu Basin, over 90% of the area has burial depths exceeding 1000 m. In the hinterland of the basin, coal seams generally exhibit burial depths greater than 1500 m, with a …