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Full-Text Articles in Earth Sciences

Enhancing Agricultural Sustainability Under Climate Change: A Multi-Scale Framework Integrating Climate Extremes, Resource Efficiency, And Data-Driven Modeling, Shahryar Fazli Dec 2026

Enhancing Agricultural Sustainability Under Climate Change: A Multi-Scale Framework Integrating Climate Extremes, Resource Efficiency, And Data-Driven Modeling, Shahryar Fazli

Computational and Data Sciences (PhD) Dissertations

Agricultural systems are increasingly challenged by climate variability, where shifting temperature regimes, hydrological variability, and the rising frequency of compound and cascading extremes threaten global food security and resource sustainability. Addressing these challenges requires integrated frameworks that bridge biophysical monitoring, predictive modeling, and adaptive decision-making. This dissertation develops a data-driven, multi-scale framework to quantify and enhance agricultural resilience by integrating remote sensing, climate analytics, and machine learning across the United States, with a focus on California and the Western U.S.

First, hyperspectral and thermal remote sensing data from EMIT and OpenET are integrated to characterize crop nitrogen–water interactions and assess …


Long-Term Analysis Of Pm2.5 Elemental Composition And Source Contributions In Coastal Urban Environments Of Corpus Christi And Houston In Texas, Sai Deepak Pinakana, Jeremy A. Sarnat, Amit U. Raysoni Dec 2026

Long-Term Analysis Of Pm2.5 Elemental Composition And Source Contributions In Coastal Urban Environments Of Corpus Christi And Houston In Texas, Sai Deepak Pinakana, Jeremy A. Sarnat, Amit U. Raysoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Long-term assessments of fine particulate matter play a key role in identifying persistent and emerging emission contributors. Coastal urban areas are highly susceptible to transboundary dust and wildfire events in addition to local pollution sources. Multi-decadal assessments in these regions using chemical speciation data could offer insights into major pollutant sources and their trends. This study utilizes nearly two decades of PM2.5 elemental composition data at two major coastal cities in Texas: Houston and Corpus Christi. Fourteen trace elements were analyzed to characterize the seasonal variability and long-term source evolution using a combination of Spearman’s correlation analysis, principal component analysis, …


Evaluating The Transformation Of Land Cover, Land Surface Temperature, And Urban Heat Island In Sylhet Division Through Geospatial Analysis, Md Fazle Rabbi Joy, Md Abdur Rahim, Md Mahfuzar Rahman, Sumiaya Amin Preota, Mohammed Mahathee Hossain Dec 2026

Evaluating The Transformation Of Land Cover, Land Surface Temperature, And Urban Heat Island In Sylhet Division Through Geospatial Analysis, Md Fazle Rabbi Joy, Md Abdur Rahim, Md Mahfuzar Rahman, Sumiaya Amin Preota, Mohammed Mahathee Hossain

School of Earth, Environmental, & Marine Sciences Faculty Publications

Rapid and unplanned urbanization has significantly transformed land use/land cover (LULC), contributing to increased land surface temperature (LST) and the emergence of urban heat islands (UHIs), especially in ecologically fragile regions. This study focuses on the Sylhet Division of Bangladesh, assessing LULC changes, LST dynamics, and UHI expansion from 1994 to 2024 using Landsat satellite imagery, normalized difference vegetation index (NDVI), normalized difference water index (NDWI) indices, and field-based LST validation. Unsupervised classification reveals a 191.75% increase in settlement areas and a 25.65% loss in forest cover. Correspondingly, the highest LST zones (> 30 °C) were absent in 1994 but …


Beyond Legacy Indices: A Critical Review Of The Modified Nemerow, Mean Enrichment Quotient, And Aggregated Multivariate Environmental Risk (Amer) Indices For Heavy Metal Pollution In Sediments, Md Shahnul Islam, Anjuman Ara Dec 2026

Beyond Legacy Indices: A Critical Review Of The Modified Nemerow, Mean Enrichment Quotient, And Aggregated Multivariate Environmental Risk (Amer) Indices For Heavy Metal Pollution In Sediments, Md Shahnul Islam, Anjuman Ara

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Background: Heavy metal pollution in sediments poses persistent ecological risks due to metal toxicity, bioaccumulation, and potential for remobilization. Legacy indices have been widely used for decades but suffer from fundamental flaws, including arbitrary background dependence, lack of grain-size normalization, and poor ecological relevance.

Objective: This review critically evaluates three emerging sediment pollution indices, the Modified Nemerow, Mean Enrichment Quotient (MEQ), and Aggregated Multivariate Environmental Risk (AMER) index, to assess their methodological advances and potential to replace legacy approaches.

Methods: A structured literature search was conducted in Web of Science, Scopus, and Google Scholar (2010–2026). Using an adapted Birch framework, …


Managing Collaboration Under Conservation Crisis: Trust, Risk, And Control In The Gulf Of Maine Fishery Management Network, Evelyn Roozee, Owen Temby, Dongkyu Kim, Antonia Sohns, Anthony Rocha Lima, Jasper R. De Vries, Gordon M. Hickey Nov 2026

Managing Collaboration Under Conservation Crisis: Trust, Risk, And Control In The Gulf Of Maine Fishery Management Network, Evelyn Roozee, Owen Temby, Dongkyu Kim, Antonia Sohns, Anthony Rocha Lima, Jasper R. De Vries, Gordon M. Hickey

School of Earth, Environmental, & Marine Sciences Faculty Publications

Transboundary fishery management and the intertwined conservation of critically endangered species represent significant governance challenges that require ongoing inter-organizational communication, collaboration, and collective action to achieve shared objectives. Previous research suggests that inter-organizational collaborative performance depends heavily on different dimensions of trust and complementary control mechanisms to mitigate the perceived risks of collaborating and enable the reciprocal sharing of resources and the coordination of activities. However, it is unclear how proposed relationships between trust, risk, and control are shaped by disruptions to established transboundary management networks. This study presents the results of survey research conducted in the Gulf of Maine …


Restructuring Our Agriculture Industry To Reduce The Eutrophication Of The Great Lakes, Kathryn B. Dunn Oct 2026

Restructuring Our Agriculture Industry To Reduce The Eutrophication Of The Great Lakes, Kathryn B. Dunn

Tredway Library Prize for First-Year Research

No abstract provided.


First Evaluation Of Contrast-Enhanced Micro-Xct As A Tool For Organismal And Reproductive Trait Observations In Corals Based On Scans Of Thesea Nivea Deichmann, 1936, Erin E. Easton Oct 2026

First Evaluation Of Contrast-Enhanced Micro-Xct As A Tool For Organismal And Reproductive Trait Observations In Corals Based On Scans Of Thesea Nivea Deichmann, 1936, Erin E. Easton

School of Earth, Environmental, & Marine Sciences Faculty Publications

Micro-X-ray computed tomography (micro-XCT) with contrast enhancement is considered a non-destructive tool that is increasingly being applied to explore the internal and external structures of vertebrates and invertebrates. Although micro-XCT has been applied to corals to study skeletal features, contrast enhancement has not been applied to evaluate the utility for visualization of soft tissue structures in corals. This study is the first to evaluate the utility of contrast enhancement to visualize internal and external features, including soft tissue features, of octocorals. Contrast staining of a Thesea nivea specimen with 2.5% Lugol's iodine permitted visualization of soft tissues with sufficient density …


Blue Carbon Ecosystems As Climate Solutions: Sequestration Across Coastal And Marine Environments, Allison K. White, Richard J. Kline, Md. Saydur Rahman Oct 2026

Blue Carbon Ecosystems As Climate Solutions: Sequestration Across Coastal And Marine Environments, Allison K. White, Richard J. Kline, Md. Saydur Rahman

School of Earth, Environmental, & Marine Sciences Faculty Publications

Blue carbon ecosystems (BCEs) such as mangroves, salt marshes, and seagrasses, sequester significant amounts of CO2 from the atmosphere. These ecosystems capture and store carbon in biomass and sediments over long periods. Other marine ecosystems, including the open ocean, kelp forests, bivalve reefs, and coral reefs, have been excluded from the BCEs, but they have the potential to serve as crucial blue carbon sinks or to support adjacent BCEs. Climate change, however, poses severe threats to these ecosystems. Rising sea levels, increasing temperatures, and ocean acidification can lead to habitat loss, reduced biodiversity, and impaired carbon sequestration capacity. Consequently, anthropogenic …


Evaluating Peak Metamorphic Conditions Of The Kyanite-Bearing Rocks At Willis Mountain, Virginia, Usa, Emma J. Hunt, Peter Horvath, Connor R. Gregory, Jade D. Sabillon, Ethan H. Watson Sep 2026

Evaluating Peak Metamorphic Conditions Of The Kyanite-Bearing Rocks At Willis Mountain, Virginia, Usa, Emma J. Hunt, Peter Horvath, Connor R. Gregory, Jade D. Sabillon, Ethan H. Watson

Earth and Environmental Sciences Publications

Willis Mountain, near Dillwyn in central Virginia, is the world’s largest kyanite deposit located in the Chopawamsic Fm. of the Piedmont province. However, little is known about the temperature and pressure conditions under which the kyanite deposit and its surrounding rocks formed, compared with similar-aged rocks in the Blue Ridge province to the southwest. Willis Mountain is composed of kyanite-bearing muscovite schists to kyanite quartzites which contain up to 55% kyanite. The following methods were used to evaluate the metamorphic conditions, with multiple calibrations for each: phase equilibrium modelling; trace element thermometry (titanium in quartz and zirconium in rutile); garnet-biotite …


Table Of Contents, The Editors Sep 2026

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Unique Connotation Of Geological-Engineering Dual Sweet Spot Evaluation For Effective Coalbed Methane Exploitation, Luo Pingya, Zhu Suyang Sep 2026

Unique Connotation Of Geological-Engineering Dual Sweet Spot Evaluation For Effective Coalbed Methane Exploitation, Luo Pingya, Zhu Suyang

Coal Geology & Exploration

Objective In China, the exploitation of deep and shallow coalbed methane (CBM) still relies on the evaluation approach oriented to the geological-engineering dual sweet spots of unconventional hydrocarbons. However, exemplary CBM production technologies delivered unsatisfactory performance in other blocks and failed to find wide application even in zones with overlapping geological and engineering sweet spots. This issue represents the principal theoretical and technical challenge confronting the comprehensive development of the CBM industry in China. Methods This study aims to elucidate the causes of this issue and provide corresponding solutions, as well as clarifying the conditions for the effective linkage between …


Exploration And Prospects Of Engineering Technologies For Deep Coal Seam Development Based On The Well Factory Mode, Gao Deli, Dong Xuelin, Bi Yansen Sep 2026

Exploration And Prospects Of Engineering Technologies For Deep Coal Seam Development Based On The Well Factory Mode, Gao Deli, Dong Xuelin, Bi Yansen

Coal Geology & Exploration

Background Given China's energy and mineral resource endowment, the efficient and green development and utilization of deep coal resources are expected to become a significant strategic option for facilitating the country's green energy transition and achieving its goals of peak carbon dioxide emissions and carbon neutrality. This significant demand may be satisfied through development using a structurally complex well factory mode. Method This study introduces the basic concept of a three-dimensional, multi-functional, and precisely controllable underground structurally complex well factory, designed for the efficient and green development of unconventional energy and mineral resources. It then discusses the well factory engineering …


Differential Accumulation Of Coalbed Methane In Medium- To Low-Rank Coal Seams In A Strongly Compressional Tectonic Setting In The Tarim Basin, Liu Honglin, Wang Hongyan, Wang Haichao, Deng Ze Sep 2026

Differential Accumulation Of Coalbed Methane In Medium- To Low-Rank Coal Seams In A Strongly Compressional Tectonic Setting In The Tarim Basin, Liu Honglin, Wang Hongyan, Wang Haichao, Deng Ze

Coal Geology & Exploration

Background The Tarim Basin contains abundant coal and coalbed methane (CBM) resources. However, the geological accumulation patterns of CBM in the basin remain poorly understood. This leads to a relative lack of targeted technologies for the exploration and development of both deep coal reservoirs and steeply dipping coal seams, further rendering it challenging to achieve breakthroughs in CBM development in the basin. Methods Based on test data from 92 coal samples, data on the drilling and production tests of more than 10 exploration wells, and 3D seismic interpretation results, this study systematically investigated the distribution of coal-bearing strata, as well …


Variable-Temperature And Variable-Pressure Adsorption Characteristics Of Deep Coalbed Methane And Their Implications, Jiang Wenping, Sun Siqing, Jin Xianglan, Tian Bofan, Tian Xinjuan Sep 2026

Variable-Temperature And Variable-Pressure Adsorption Characteristics Of Deep Coalbed Methane And Their Implications, Jiang Wenping, Sun Siqing, Jin Xianglan, Tian Bofan, Tian Xinjuan

Coal Geology & Exploration

Background Investigating the adsorption characteristics of coalbed methane (CBM) helps bridge key geological information concerning deep CBM, including occurrence state, free gas proportion, and gas-bearing properties, with the gas production potential and commercial exploitation of CBM wells. Such investigation represents a key component of the evaluation, exploration, and exploitation of CBM reservoirs. Methods Using deep coal samples collected from three representative regions, this study designed high-temperature and high-pressure methane isothermal adsorption experiments, together with variable-temperature and variable-pressure methane adsorption experiments, using nuclear magnetic resonance (NMR). The adsorption characteristics of the coal samples derived using the different experimental methods were subsequently …


Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu Sep 2026

Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu

Coal Geology & Exploration

Background Deep coalbed methane (CBM) holds an important strategic position in China's unconventional natural gas system. However, concerning deep CBM occurrence, there remains a lack of systematic quantitative understanding of the underlying mechanisms and the controlling effects of pore structure. Methods This study investigated high-rank coal samples collected at a burial depth of approximately 2000 m from the No. 8 coal seam in the Daning-Jixian block along the eastern margin of the Ordos Basin. Using multiscale pore characterization techniques, including low-temperature liquid nitrogen adsorption, high-pressure mercury injection, and low-temperature CO2 adsorption, the full-scale pore size distribution of the coal …


Controlling Effects Of Ash Yield On The Adsorption-Desorption Behavior And Production Potential Of Methane In Deep Coal Reservoirs, Huang Daojun, Liu Xinshe, Chen Shida, Sun Wen, Jiao Pengshuai, Wang Huaichang Sep 2026

Controlling Effects Of Ash Yield On The Adsorption-Desorption Behavior And Production Potential Of Methane In Deep Coal Reservoirs, Huang Daojun, Liu Xinshe, Chen Shida, Sun Wen, Jiao Pengshuai, Wang Huaichang

Coal Geology & Exploration

Objective The lithotype and quality characteristics of coals significantly affect the reservoir permeability and production potential of coalbed methane (CBM). However, there remains a lack of clear understanding of the controlling effects of ash yield on the gas-bearing properties and methane adsorption-desorption behavior of coal seams under comparable thermal maturity. Focusing on coal samples obtained through continuous sealed coring from the No. 8 coal seam in well M172 in the east-central part of the Ordos Basin, this study aims to clarify the impacts of ash yield on the pore structure, adsorption capacity, desorption process, and resource recoverability. This effort is …


Components And Isotope Fractionation Of Deep Coalbed Methane And Their Geological Implications In The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Zhang Yun, Wang Hongna, Chen Yiyu, Chen Gaojie, Wang Jun, Liu Lingqi, Li Panxue, He Hongcheng, Li Wenbiao Sep 2026

Components And Isotope Fractionation Of Deep Coalbed Methane And Their Geological Implications In The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Zhang Yun, Wang Hongna, Chen Yiyu, Chen Gaojie, Wang Jun, Liu Lingqi, Li Panxue, He Hongcheng, Li Wenbiao

Coal Geology & Exploration

Objective The components of deep coalbed methane (CBM), along with its isotopic composition and fractionation patterns, hold great significance for revealing the genetic types, occurrence characteristics, flow, and production patterns of CBM. Methods This study investigated the Shanxi and Benxi formations in the Daning-Jixian block, Ordos Basin. A range of analyses and tests were conducted, including field CBM desorption experiments on coal samples from the deep parts of both formations, continuous monitoring of wellhead gas from two production wells, physical property tests on the samples, organic petrological experiments, and geochemical analysis. Furthermore, this study analyzed the components and isotopes of …


Investigating The Mechanisms Controlling Gas Flow In Coal Reservoirs Based On Multi-Scale Digital Rocks, Han Lei, Huang Dongxiang, Zhang Xiaodong, Shen Jian, Zhang Shuo, Ni Xiaoming, Liu Xiao Sep 2026

Investigating The Mechanisms Controlling Gas Flow In Coal Reservoirs Based On Multi-Scale Digital Rocks, Han Lei, Huang Dongxiang, Zhang Xiaodong, Shen Jian, Zhang Shuo, Ni Xiaoming, Liu Xiao

Coal Geology & Exploration

Background Deep coal reservoirs exhibit highly heterogeneous pore-fracture structures. However, limited by a single imaging resolution, conventional digital rock techniques struggle to characterize complex pore-fracture networks across multiple scales. This poses significant scientific challenges for the fine-scale characterization of deep coal reservoirs and the investigation of their seepage mechanisms. Methods This study investigated deep coalbed methane (CBM) reservoirs in the north-central Qinshui Basin. The pore-fracture structures of coal samples were characterized by integrating X-ray computed tomography (CT), mercury injection capillary pressure (MICP), and scanning electron microscopy (SEM). Digital rock models incorporating multi-scale pores and fractures were then constructed by integrating …


Investigating The Characteristics Of Ch4 Adsorption In Coal Reservoirs Based On Interpretable Machine Learning, Chen Ruibin, Zhou Sandong, Zhang Weixin, Yan Detian, Wang Hua Sep 2026

Investigating The Characteristics Of Ch4 Adsorption In Coal Reservoirs Based On Interpretable Machine Learning, Chen Ruibin, Zhou Sandong, Zhang Weixin, Yan Detian, Wang Hua

Coal Geology & Exploration

Objective Accurately predicting methane (CH4) adsorption capacity in coal reservoirs is critical to the efficient exploration and exploitation of coalbed methane (CBM). Existing studies largely rely on experimental data from a small number of samples and theoretical adsorption models such as Langmuir. However, these studies exhibit time-consuming and laborious processes, as well as conclusions with limited generalizability, posing challenges to their widespread applications across different basins. Methods Based on 1150 sets of experimental data on CH4 adsorption in coals, this study investigated five machine learning models, namely artificial neural network (ANN), support vector machine (SVM), K-nearest neighbor …


Mechanical Anisotropy And Depth Effects Of Deep Coal Seams, Mei Xiaofan, Wang Cong, Wang Kaifeng, Tang Shuheng, Zhang Songhang, Xi Zhaodong Sep 2026

Mechanical Anisotropy And Depth Effects Of Deep Coal Seams, Mei Xiaofan, Wang Cong, Wang Kaifeng, Tang Shuheng, Zhang Songhang, Xi Zhaodong

Coal Geology & Exploration

Objective The mechanical properties of coal seams determine the stability, fracability, and fracturing performance of deep coal reservoirs. Since the in situ stress applied to coal increases with burial depth, deep coal differs from its shallow counterpart in damage behavior, key mechanical parameters, and failure mechanism. Furthermore, deep coal exhibits pronounced mechanical anisotropy.Methods Focusing on the No. 9 coal seam in the Linxian area along the eastern margin of the Ordos Basin, this study carried out triaxial compression tests at 60℃ under different confining pressures to determine the mechanical anisotropy of deep coal. By comparing the full stress-strain curves, …


An Improved Brittleness Characterization Method For Deep Coalbed Methane Reservoirs And Its Application To Well Logs, Huang An’Er, Gong Fei, Peng Suping, Zou Guangui, Zhang Zhaoji, Wu Yiquan, Rong Zhihong, Li Qingrun Sep 2026

An Improved Brittleness Characterization Method For Deep Coalbed Methane Reservoirs And Its Application To Well Logs, Huang An’Er, Gong Fei, Peng Suping, Zou Guangui, Zhang Zhaoji, Wu Yiquan, Rong Zhihong, Li Qingrun

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs are characterized by high pressure, low porosity, and low permeability. Therefore, large-scale volume fracturing is required for their commercial development. As an important engineering sweet spot parameter for selecting optimal fracturing targets, the brittleness index can reflect the difficulty in generating complex fracture networks during fracturing. However, existing brittleness characterization methods are largely applicable to strata with high brittle mineral content, such as shales and sandstones, while methods for characterizing the brittleness of deep CBM reservoirs with high organic matter content and low brittle mineral content are lacking. Methods Rock physics experiments on 20 …


A Fault Identification Method For Deep Coalbed Methane Reservoirs Based On An Improved Transunet, Gao Congshun, Wu Haibo, Liu Lei, Wang Zijian, Huang Xuanyu, Jia Lilan, Xu Aiguo Sep 2026

A Fault Identification Method For Deep Coalbed Methane Reservoirs Based On An Improved Transunet, Gao Congshun, Wu Haibo, Liu Lei, Wang Zijian, Huang Xuanyu, Jia Lilan, Xu Aiguo

Coal Geology & Exploration

Objective Small-scale faults in deep coalbed methane (CBM) reservoirs significantly affect CBM enrichment and the deployment of development wells. However, deep seismic data tend to suffer from low signal-to-noise ratios (SNRs) and poor continuity of reflection events, while conventional methods are likely to miss small-scale faults. To address these limitations, this study proposes a fault identification method based on an improved TransUNet. Methods The proposed method is developed based on the R50-ViT-B_16 TransUNet architecture. A coordinate attention (CA) module is introduced before the skip connections enter the decoder to enhance the feature representation of the locations and directional continuity of …


Petrophysical Model-Driven Seismic Inversion For Physical Property Parameters Of Deep Coalbed Methane Reservoirs, Chen Yang, Guo Qiang, Ba Jing Sep 2026

Petrophysical Model-Driven Seismic Inversion For Physical Property Parameters Of Deep Coalbed Methane Reservoirs, Chen Yang, Guo Qiang, Ba Jing

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) reservoirs typically exhibit complex pore-fracture structures, as well as strong nonlinear and non-unique corresponding relationships between elastic and physical property parameters. In this context, this study develops a seismic petrophysical inversion method that accounts for pore structure variations. Methods This study investigated deep CBM reservoirs along the eastern margin of the Ordos Basin. First, a petrophysical model based on variable pore aspect ratios was established, and the corresponding linearized forward operator was derived. Then, the pore aspect ratios were estimated using near-borehole log data. Meanwhile, the multimodal prior distributions of reservoir physical property parameters were …


Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang Sep 2026

Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang

Coal Geology & Exploration

Objective Coal macrolithotype represents a key geological property in the exploration and recovery of deep coalbed methane (CBM) resources, and its accurate identification is of great significance for selecting the optimal geological and engineering sweet-spot intervals. However, conventional coal macrolithotype identification relies heavily on core observation, suffering from prohibitively high costs since core data are extremely valuable and thus feature a small sample size. Meanwhile, conventional log-based threshold methods face challenges in effectively characterizing the complex boundaries between coal macrolithotypes.Methods This study investigated the No. 8 coal seam of the Benxi Formation, Shenmu area, eastern Ordos Basin. Based on …


A Probabilistic Lithofacies Classification Method For Deep Coal Measures, Xu Aiguo, Zhang Pingsong, Wu Haibo, Li Shenglin Sep 2026

A Probabilistic Lithofacies Classification Method For Deep Coal Measures, Xu Aiguo, Zhang Pingsong, Wu Haibo, Li Shenglin

Coal Geology & Exploration

Background Deep coal measures contain multiple unconventional reservoir types, including coal, shale, and tight sandstone. Accurate lithofacies classification helps identify the resource and engineering targets of unconventional gas within these deep sequences, thus guiding category-based extraction and efficient development. However, conventional lithofacies classification methods largely rely on elastic parameters derived based on the isotropic-medium assumption or linear amplitude variation with offset (AVO) inversion while neglecting the pronounced vertical transverse isotropy (VTI) anisotropy of deep coal measures, severely limiting the lithofacies classification accuracy. Methods This study develops a probabilistic lithofacies classification method for deep coal measures. First, high-accuracy elastic parameters, including …


Multi-Round Diverting Fracturing Technology For Deep-Seated Thin Coal Seams And Its Application: A Case Study Of The G3-1 Well Group In The Yichuan Block, Ordos Basin, Li Shuguang, Nie Zhihong, Ji Liang, Zhou Changhui, Bai Kunsen, Huang Li, Zhen Huaibin, Xing Xuejie, Zhao Haifeng Sep 2026

Multi-Round Diverting Fracturing Technology For Deep-Seated Thin Coal Seams And Its Application: A Case Study Of The G3-1 Well Group In The Yichuan Block, Ordos Basin, Li Shuguang, Nie Zhihong, Ji Liang, Zhou Changhui, Bai Kunsen, Huang Li, Zhen Huaibin, Xing Xuejie, Zhao Haifeng

Coal Geology & Exploration

Objective Deep coal seams in the Yichuan block of the Ordos Basin are characterized by small thicknesses, vertical multi-layer superimposition, and strong vertical and horizontal heterogeneities. When used to develop these coal seams, multi-stage horizontal well fracturing faces challenges such as uneven fracture propagation across various stages in the horizontal direction and a low production degree of multiple coal seams in the vertical direction, complicating commercial exploitation. To address these issues, this study proposes a multi-round diverting fracturing technology based on a vertical cluster well group. In this technology, vertical layered fracturing using vertical cluster wells is employed to achieve …


Scaling And Blockage In Deep Coalbed Methane Wells: Mechanisms And Countermeasures, Zhang Lei, Chen Ming, Zhen Huaibin, Zeng Wenting, Hao Pengcheng, Hou Wei, Yin Decai, Zhang Kang, Liu Chuanqing, Tian Zhida, Liu Qihu, Wang Qian, Xiong Wei, Sun Weiwei, Xia Fei, Wang Chunyan Sep 2026

Scaling And Blockage In Deep Coalbed Methane Wells: Mechanisms And Countermeasures, Zhang Lei, Chen Ming, Zhen Huaibin, Zeng Wenting, Hao Pengcheng, Hou Wei, Yin Decai, Zhang Kang, Liu Chuanqing, Tian Zhida, Liu Qihu, Wang Qian, Xiong Wei, Sun Weiwei, Xia Fei, Wang Chunyan

Coal Geology & Exploration

Background The exploitation of deep coalbed methane (CBM) is accompanied by continuous pressure drawdown. In this case, scaling and blockage are prone to occur in systems where formation water with high total dissolved solids (TDS) and high-concentration CO2 coexist. In the middle to late production stage, the blockage of both wellbore and flow pathways in reservoirs frequently leads to abrupt declines in gas production and bottomhole pressure or even induces the shutdown of natural flowing production, severely restricting the stable production of deep CBM wells. Methods This study investigated the Daning-Jixian block in the eastern Ordos Basin. Using multiple …


Technology Roadmap And Countermeasures For Lean Development Of Low-Grade Deep Coalbed Methane: A Case Study Of The Linxing-Shenfu Block, Ordos Basin, Wu Guang’Ai, Xing Xuesong, Wu Jianshu, Zhu Ying, Zi Jingyu, Wang Zhi, Hou Yanan, Cheng Yuxiong, Liu Xin Sep 2026

Technology Roadmap And Countermeasures For Lean Development Of Low-Grade Deep Coalbed Methane: A Case Study Of The Linxing-Shenfu Block, Ordos Basin, Wu Guang’Ai, Xing Xuesong, Wu Jianshu, Zhu Ying, Zi Jingyu, Wang Zhi, Hou Yanan, Cheng Yuxiong, Liu Xin

Coal Geology & Exploration

Background Accelerating deep coalbed methane (CBM) exploitation is a strategic initiative for the energy security and energy mix optimization of China. The Linxing-Shenfu block in the Ordos Basin holds considerable resource potential of deep CBM. However, this block exhibits typical geological characteristics of low-grade deep CBM, including the complete absence of free gas, gas content < 14 m3/t, reservoir permeability < 0.1 × 10−3 μm2, and strong heterogeneity. These characteristics lead to low efficiency of conventional development models. Therefore, there is an urgent need to develop an efficient technical system tailored to these characteristics. Method To address the core contradiction between reservoir …


Numerical Simulation Of Stress Shadow Effect And Cluster Spacing Optimization For Multi-Cluster Fracturing In Deep Coalbed Methane Horizontal Wells, Guo Guangshan, Deng Zhiyu, Sun Le, Pu Yifan, Wu Jian, Tao Shu, Chen Shaojuan, Chen Shida Sep 2026

Numerical Simulation Of Stress Shadow Effect And Cluster Spacing Optimization For Multi-Cluster Fracturing In Deep Coalbed Methane Horizontal Wells, Guo Guangshan, Deng Zhiyu, Sun Le, Pu Yifan, Wu Jian, Tao Shu, Chen Shaojuan, Chen Shida

Coal Geology & Exploration

Purpose Multi-stage, multi-cluster fracturing in horizontal wells represents a key technique for deep coalbed methane (CBM) recovery and the sustainable development of the industry. However, during multi-cluster fracturing in deep CBM horizontal wells, the stress shadow effect tends to induce non-uniform fracture propagation and a limited stimulated reservoir volume (SRV). Methods To address these challenges. this study established a two-dimensional (2D) numerical model for multi-cluster hydraulic fracturing in horizontal wells using the finite element method. Then, it systematically analyzed the impacts of in situ stress and cluster spacing on both the stress shadow effect and the competitive propagation of hydraulic …


Fracturing With Three-Dimensional Full-Scale Fracture Network Propping For Deep Coalbed Methane Reservoirs: A Novel Ceramic Micro-Proppant And Its Verification Through Numerical Simulations, Li Xiang, Xu Jun, Li Ting, Zhang Xiaoyu, Yang Bo Sep 2026

Fracturing With Three-Dimensional Full-Scale Fracture Network Propping For Deep Coalbed Methane Reservoirs: A Novel Ceramic Micro-Proppant And Its Verification Through Numerical Simulations, Li Xiang, Xu Jun, Li Ting, Zhang Xiaoyu, Yang Bo

Coal Geology & Exploration

Objective and Methods Conventional fracturing struggles to achieve the long-term effective propping of complex fracture networks during the development of deep coalbed methane (CBM) reservoirs. To address this challenge, this study developed a novel ceramic micro-proppant suitable for the volumetric microfracture propping and, through numerical simulations, verified its performance when it was applied to reservoir stimulation in conjunction with the technology of fracturing with three-dimensional full-scale fracture network propping. First, a novel ceramic micro-proppant with a core-shell structure was designed according to the requirements of microfracture propping. Its key properties, including compressive strength, settling behavior, hydraulic conductivity, and stability, were …