Non-uniform Distributions of Gas Pressure and Coal Permeability in Coalbed Methane Reservoirs Induced by the Loess Plateau Geomorphology: A Case Study in Ordos Basin,China

Natural Resources Research - Coal mine methane (CMM) accumulation and permeability distribution characterization are the bases for a successful CMM drainage design. Before extending degassing...     

Characterization and Quantification of Mining-Induced Fractures in Overlying Strata: Implications for Coalbed Methane Drainage

Natural Resources Research - Coalbed methane (CBM) production in the overlying strata of coal reservoirs is often hampered by the unknown distribution of the mining-induced fractures....     

Differentiation of Carbon Isotope Composition and Stratabound Mechanism of Gas Desorption in Shallow-Buried Low-Rank Multiple Coal Seams: Case Study of Well DE-A,Northeast Inner Mongolia

Natural Resources Research - The desorbed gas composition and δ13C(CH4) and δD(CH4) of five coal groups in Well DE-A of the Labudalin Basin in northeastern Inner Mongolia show that the...     

Mechanical and Acoustic Emission Characteristics of Coal at Temperature Impact

Natural Resources Research - Coal and rock mass constitute a type of porous medium. This study investigated the influence of temperature impact on the mechanical properties and acoustic emission...     

Disaster-Triggering Mechanisms Based on Interaction of Various Factors in Structured Gas Migration in Coal Seams Under Loading and Unloading Conditions

Natural Resources Research - On the premise that the point of the maximum abutment pressure is the demarcation point of gas migration, an experimental research was conducted on gas-bearing coal by...     

Permeability Characteristics of Broken Coal and Rock Under Cyclic Loading and Unloading

Natural Resources Research - During longwall mining, the permeability evaluation in a caving zone is one of the most challenging risks for mine operators because it controls the behavior of gas...     

Co-production of Tight Gas and Coalbed Methane from Single Wellbore: a Simulation Study from Northeastern Ordos Basin,China

Natural Resources Research - Focusing on vertical multi-layer superimposition of unconventional natural gas reservoirs in coal-bearing strata, research on the co-production of tight gas and coalbed...     

Acoustic Emission and Energy Dissipation Characteristics of Gas-Bearing Coal Samples Under Different Cyclic Loading Paths

Natural Resources Research - Cyclic loading widely exists in coal mining activities, and it can significantly change the mechanical and seepage characteristics of coal. In this study, raw...     

Experimental Investigation of Anisotropic Thermal Deformation of Oil Shale Under High Temperature and Triaxial Stress Based on Mineral and Micro-fracture Characteristics

Natural Resources Research - The anisotropic deformation of oil shale at different temperatures should be given particular attention considering that thermal deformation affects borehole stability,...     

华北主要城市夏季高温气候特征及评估方法

利用我国华北地区1961~2000年夏季6~8月高温资料,探讨了华北地区主要城市高温过程,建立该地区强高温过程较完整的序列。分析华北主要城市北京、天津、石家庄、济南、太原市等夏季危害性高温气候特征。给出了东亚副热带高压和大陆变性高压的活动特点。观测结果表明,东亚副热带高压和大陆变性高压对华北地区主要城市夏季危害性高温在各地有很大差异,与相对湿度大小有密切关系。东亚副热带高压和大陆变性高压的活动是造成华北地区城市夏季危害性高温的主要影响系统。在此基础上建立了华北主要城市夏季危害性高温候、旬、月评估方法。其结果表明该方法对华北地区主要城市夏季危害性高温影响评估有应用价值。     

瞬变电磁法解释煤矿地下含水构造研究——以内蒙古东明露天矿为例

内蒙古呼伦贝尔东明露天煤矿矿坑边帮地下水渗漏的问题日益严重,矿区原有的疏干降水井排水能力及效果已不能满足生产需求,同时对矿区生态环境也造成一定程度破坏。目前,对矿区周边的水文地质条件和水力联系缺乏精准全面的认识和数据。通过瞬变电磁法对矿区地下水渗漏较严重的西北部进行三条勘探线(77个物理点)勘查,结果表明该区存在三处视电阻率低阻异常带,判定其主要为含水断层(裂隙)所致;结合矿区地形、地层岩性与矿区地下水矿化度,对上述异常带进行了科学合理的综合解释,并结合新施工的疏干降水井抽水验证了上述异常的可靠性,为矿区后期布置疏干降水井圈定了靶区,对当地同类型矿区地下水渗漏灾害治理起到了应用示范作用。     

中国沙尘暴分布规律及研究方法分析

在分析中国沙尘暴研究现状的基础上,对其时空分布规律、沙尘源地、移动路径、研究方法和手段进行了系统的总结。结果表明,中国沙尘暴分布与北方的沙漠、沙地、戈壁等荒漠化地区分布一致,存在4大沙尘源区。干枯的湖泊、弃荒土地、沙砾草场可能成为东北地区的主要沙源,应引起注意;沙尘暴移动路径主要有3条,分别归纳了各路径的特征;根据沙尘源区示踪方法的特点和实例,指出了适用条件和应用范围,为今后沙尘暴的研究和防治提供依据和思路。     

Gas Flow Characteristics and Optimization of Gas Drainage Borehole Layout in Protective Coal Seam Mining: A Case Study from the Shaqu Coal Mine,Shanxi Province,China

With increasing demands for coal resources, coal has been gradually mined in deep coal seams. Due to high gas content, pressure and in situ stress, deep coal seams show great risks of coal and gas outburst. Protective coal seam mining, as a safe and effective method for gas control, has been widely used in major coal-producing countries in the world. However, at present, the relevant problems, such as gas seepage characteristics and optimization of gas drainage borehole layout in protective coal seam mining have been rarely studied. Firstly, by combining with formulas for measuring and testing permeability of coal and rock mass in different stress regimes and failure modes in the laboratory, this study investigated stress–seepage coupling laws by using built-in language Fish of numerical simulation software FLAC^3D. In addition, this research analyzed distribution characteristics of permeability in a protected coal seam in the process of protective coal seam mining. Secondly, the protected coal seam was divided into a zone with initial permeability, a zone with decreasing permeability, and permeability increasing zones 1 and 2 according to the changes of permeability. In these zones, permeability rises the most in the permeability increasing zone 2. Moreover, by taking Shaqu Coal Mine, Shanxi Province, China as an example, layout of gas drainage boreholes in the protected coal seam was optimized based on the above permeability-based zoning. Finally, numerical simulation and field application showed that gas drainage volume and concentration rise significantly after optimizing borehole layout. Therefore, when gas is drained through boreholes crossing coal seams during the protective coal seam mining in other coal mines, optimization of borehole layout in Shaqu Coal Mine has certain reference values.

     

神府东胜煤田开发中人为泥石流发育现状及其分布特征

神府东胜煤田我国本世纪重要能源供应地，90年代大规模开发以来泥石流频繁发生，通过实地考察发现：神府东胜煤田泥石流规模小、同人为诱发的人为泥石流，泥石流的分布特征与人工采石场等弃土弃堆放地的分布紧密对应；泥石流呈集群式分布，与地面物质组成密切相关；泥石流主要分布在面积为1km^2以下的二级沟里。     

跨国人口迁移新特征下的移民研究转向——移民产业概念的提出、发展与应用

基于西方学界中移民产业的相关文献,系统梳理了移民产业概念的形成、发展与应用。研究发现：首先,移民产业概念在分析尺度上将宏观与微观相结合,并引入多主体分析的视角,因此其在解释跨国人口迁移在不同阶段的特征与机制方面显现出相对的灵活性;其次,移民产业概念主要被应用于解释流动性机制、跨国移民治理、跨国移民的在地化3个方面。通过对移民产业概念的渊源、发展和相关实证研究的梳理,以期为中国的移民研究提供新的视角、为移民管制及移民政策的制订提供参考与借鉴。     

Waveform Characteristics of Earthquakes Induced by Hydraulic Fracturing and Mining Activities: Comparison with Those of Natural Earthquakes

Natural Resources Research - Some industrial activities, such as underground mining, hydraulic fracturing (HF), can cause microearthquakes and even damaging earthquakes. In recent years, with the...     

职住分离的度量方法与空间组织特征——以北京市轨道交通对职住分离的影响为例

基于问卷调查获取的万份调查数据,构建了以通勤时间/距离为基础数据的职住分离度量模型,即基于频数分布法的通勤时间/距离和基于不同时段/区段范围内居民分布结构的"职住分离强度指数".根据上述判别模型与计算结果,发现:①各样本区居民通勤时间普遍增加,城市外围区轨道交通沿线居民通勤时间多数集中在40分钟以上,自购居民的通勤时间...     

老年人公交活动空间特征及影响因素研究——基于日常与偶发活动的对比分析

公交出行对保障老年人生活质量具有重要意义。论文以安徽省芜湖市区为研究区域,从频率分异的视角出发研究老年人公交活动空间,利用公交刷卡数据,对比分析日常与偶发活动空间的分布特征,并进一步借助地理加权回归方法探讨建成环境对其影响机制的差异。研究发现：① 老年人日常和偶发公交活动空间呈现出相似的圈层式空间分布特征,但偶发活动的圈层结构层次相对更加明显;② 日常与偶发活动空间的影响机制存在差异,建成环境在不同空间的影响强度和方向存在明显不同,尤其表现在城市外围空间。研究结果有助于更加全面地解读老年人活动空间的结构层次,并为面向不同城市空间、不同类型设施的系统性规划建设提供参考。