鄂庄煤矿2煤层瓦斯地质规律研究

通过对鄂庄煤矿2煤层采掘区井下钻孔瓦斯煤样直接法测试结果及勘探钻孔瓦斯样资料的综合分析,阐明了影响鄂庄井田2煤层瓦斯赋存的主要地质因素和矿井未采区煤层瓦斯含量预测的思路和方法.探讨了鄂庄井田2煤层瓦斯赋存的规律.在分析低瓦斯矿井瓦斯涌出特点和影响因素的基础上,指出瓦斯异常涌出是低瓦斯矿井瓦斯防治的重点.     

黄陵二号煤矿瓦斯地质规律及涌出量预测

用地质观点研究煤层瓦斯赋存已获得实践检验,瓦斯的赋存及涌出与地质因素密不可分.在收集并整理黄陵二号煤矿井田地质资料和瓦斯资料的基础上,分析了井田地质构造特征,结合瓦斯地质理论,研究地质构造、煤层顶底板岩性、煤层埋藏深度、水文地质条件等因素对瓦斯赋存的影响,融合矿井勘探及生产期间实测瓦斯含量数据,采用瓦斯地质统计法建立回采面绝对瓦斯涌出量与煤层瓦斯含量的关系式,并以此对矿井未采区的瓦斯涌出量进行了预测.     

用多元线性回归分析法预测矿井深部瓦斯涌出量

利用常村井田 2 1采区一分层回采时实测的绝对瓦斯涌出量数据和采区内 1 2个钻孔的原始数据 ,用多元线性回归分析法 ,找出了控制瓦斯涌出量的主要地质因素是煤层厚度和煤层埋深 .根据回归方程 ,计算出矿井瓦斯梯度为每百米增加 0 .67m3/min ,并对矿井深部一分层开采时的瓦斯涌出量进行了预测 .以 5m3/min绝对瓦斯涌出量等值线为界 ,把整个井田划分为低瓦斯区和中高瓦斯区 ,指出在矿井深部煤层开采时 ,必须提前制定出防止瓦斯事故发生的有效措施     

龙永煤田瓦斯地质因素初探

在介绍龙永煤田地质概况的基础上,分析了矿区瓦斯涌出特征;从煤层顶、底板岩性特征、地质构造、煤层埋藏深度和地下水等方面分析了影响瓦斯赋存的地质因素,对可能出现高瓦斯的井田(块段)或矿井进行了预测.     

龙永煤田瓦斯地质因素初探

在介绍龙永煤田地质概况的基础上,分析了矿区瓦斯涌出特征;从煤层顶、底板岩性特征、地质构造、煤层埋藏深度和地下水等方面分析了影响瓦斯赋存的地质因素,对可能出现高瓦斯的井田(块段)或矿井进行了预测.     

用多元线性回归分析法预测矿井深部瓦斯涌出量

利用常村井田21采区一分层回采时实测的绝对瓦斯涌出量数据和采区内12个钻孔的原始数据,用多元线性回归分析法,找出了控制瓦斯涌出量的主要地质因素是煤层厚度和煤层埋深.根据回归方程,计算出矿井瓦斯梯度为每百米增加0.67*!m3/min,并对矿井深部一分层开采时的瓦斯涌出量进行了预测.以5*!m3/min绝对瓦斯涌出量等值线为界,把整个井田划分为低瓦斯区和中高瓦斯区,指出在矿井深部煤层开采时,必须提前制定出防止瓦斯事故发生的有效措施.     

金发煤矿开采层瓦斯地质规律研究及危险性预测

矿井瓦斯赋存规律及涌出量预测是矿井瓦斯治理的重要理论依据.深入研究分析了金发煤矿瓦斯地质赋存规律控制因素,定性分析了金发煤矿地质构造、煤层上覆基岩厚度、顶底板岩性、水文地质条件等控制要素,确定埋深是影响矿井C8、C9煤瓦斯含量最重要因素.结合矿井实测瓦斯涌出量,预测了煤与瓦斯区域突出危险性.结果表明:煤层埋深与瓦斯含量呈正相关关系;瓦斯压力是判定该矿C8、C9煤瓦斯突出危险性的最重要指标,矿界内煤层瓦斯压力大于0.74 MPa的区域具有突出危险性,煤矿的突出危险区主要在矿界西北边靠近矿2坐标点附近.     

上京井田顺层滑动构造对瓦斯赋存的控制

本文通过对上京井田顺层滑动构造的形迹特征、空间展布特征和瓦斯涌出特征的分析，讨论了顺层滑动构造对该井田煤层中瓦斯赋存的控制，认为顺层滑动构造是造成煤层中瓦斯赋存异常的最主要因素之一，瓦斯含量的高低与顺层滑动构造发育程度密切相关。     

上京井田顺层滑动构造对瓦斯赋存的控制

本文通过对上京井田顺层滑动构造的形迹特征、空间展布特征和瓦斯涌出特征的分析，讨论了顺层滑动构造对该井田煤层中瓦斯赋存的控制，认为顺层滑动构造是造成煤层中瓦斯赋存异常的最主要因素之一，瓦斯含量的高低与顺层滑动构造发育程度密切相关。     

文宾山井田地质条件对瓦斯赋存的影响及防范措施

通过分析漳平文宾山井田地质条件对瓦斯赋存的影响,提出要查清低瓦斯矿井煤层瓦斯的富集区,编制瓦斯含量预测图,并完善矿井通风系统及瓦斯管理工作,采取必要的防范措施,才能更好地为煤矿安全生产服务.     

两软一硬煤层突出控制因素与发生规律

针对两软一硬煤层特殊的瓦斯地质条件,以云盖山井田一矿二1煤层为例,探寻了两软一硬煤层煤与瓦斯突出的控制因素,分析了掘进工作面掘进期间突出预测指标的分布特征,总结归纳了"两软一硬"煤层煤与瓦斯突出发生规律.研究结果表明,由于地质构造变动,云盖山一矿二1煤层产状变化较大,煤层倾角发生急剧变化的地带,地应力集中;受层间滑动构造的影响,煤层厚度变化较大,具有突然增厚、变薄以至尖灭、挤灭现象;二1煤层构造软煤呈连续层状发育.因此,在煤层薄、厚交接处(煤层急剧变化带),小断层附近,应力集中,瓦斯积聚,煤体破坏严重,易发生突出.此项研究,可为地质条件类似矿井开展瓦斯地质研究和瓦斯灾害防治工作提供方法借鉴和理论指导.     

煤矿深部开采煤层气含量计算的解析法

针对矿井深部煤层中地温和地应力梯度对煤的孔隙率和煤层渗透率的影响以及煤的吸附特性参数受温度影响变化的特点 ,在矿井深部煤层气压力解析算法的基础上 ,提出了考虑地温和地应力梯度影响的煤层气含量计算的新方法 .现场实测煤层气压力和理论计算的煤层气压力及煤层气含量的对比分析表明 ,该计算方法能较准确地反映现场实测结果 ,从理论上进一步完善了矿井深部煤层煤层气含量的计算方法 ,并对其分布规律的预测具有重要理论价值 .     

Exploitation technology of pressure relief coalbed methane in vertical surface wells in the Huainan coal mining area

Exploitation technology of pressure relief coalbed methane in vertical surface wells is a new method for exploration of gas and coalbed methane exploitation in mining areas with high concentrations of gas, where tectonic coal developed. Studies on vertical surface well technology in the Huainan Coal Mining area play a role in demonstration in the use of clean, new energy re-sources, preventing and reducing coal mine gas accidents and protecting the environment. Based on the practice of gas drainage engineering of pressure relief coalbed methane in vertical surface wells and combined with relative geological and exploration en-gineering theories, the design principles of design and structure of wells of pressure relief coaibed methane in vertical surface wells are studied. The effects of extraction and their causes are discussed and the impact of geological conditions on gas production of the vertical surface wells are analyzed. The results indicate that in mining areas with high concentrations of gas, where tectonic coal developed, a success rate of pressure relief coalbed methane in surface vertical well is high and single well production usually great. But deformation due to coal exploitation could damage boreholes and cause breaks in the connection between aquifers and bore-holes, which could induce a decrease, even a complete halt in gas production of a single well. The design of well site location and wellbore configuration are the key for technology. The development of the geological conditions for coalbed methane have a sig-nificant effect on gas production of coalbed methane wells.     

Status of research on biogenic coalbed gas generation mechanisms

Biogenic coalbed gas,how it is generated and the geochemical characteristics of the gas are gaining global attention.The ways coalbed gas is generated,the status of research on the generation mechanism and the methods of differentiating between biogenic gasses are discussed.The generation of biogenic coalbed methane is consistent with anaerobic fermentation theory.Commercial biogenic coalbed gas reservoirs are mainly generated by the process of CO2 reduction.The substrates used by the microbes living in the coal include organic compounds,CO2,H2 and acetate.The production ratio and quantity of biogenic coalbed methane depend on the exposed surface area,the solubility and permeability of the coal and the microbial concentration in the coal seam.It is generally believed that biogenic coalbed gas has a value for σ13C1＜-5.5%,C1/C1+＞0.95.The H isotope ratio is controlled by both the environment and the generation mechanism:typically σD1＜-20%.Biogenic methane formed by CO2 reduction has more σD1 than that formed by acetate fermentation.     

煤田瓦斯涌出与地质因素关系的初步探讨

以苏邦井田几个开采中的矿井瓦斯地质统计资料为依据，对煤体中瓦斯涌出与井田的地质构造、煤层埋藏深度、围岩性质等地质因素之间的关系进行了探讨。     

沁水盆地南部煤层气藏特征

以油气、煤田和煤层气勘探阶段积累的资料为基础,系统探讨了沁南煤层气藏的特征.通过对气藏静态特征(包括煤层空间几何形态、煤层气成分和含量、储层物性、吸附特征、储层压力及封闭条件)和动态过程(包括煤层气形成、运移和聚集)的分析,指出晚古生代的煤层在经历了印支期和燕山期两次煤化作用生成的煤层气,在喜马拉雅期遭受了严重的调整与改造后逐渐形成现今的沁南煤层气藏.直接控制该煤层气藏中煤层气富集程度的因素为顶底板与边界断层.目前的高产煤层气井基本上都位于地下水滞流区.     

中国煤储层岩石物理学因素控气特征及机理

基于全国主要矿区或勘探区统计资料,总结了煤级、煤岩类型、显微组分组成等煤的岩石物理学因素与煤层含气量、吸附性、渗透性等之间的关系,探讨了煤储层岩石物理学特征的控气作用机理．发现煤级－含气量的“包络线”具有阶段性演化规律,最大含气量的显著变化与煤化作用阶跃高度一致,煤储层含气量较高的地区沿纬向等间距展布且与较高煤级煤分布区吻合,煤的兰氏体积与镜质组含量关系中存在一个镜质组含量临界值．指出不同煤化作用阶段控气作用的实质在于煤物理结构和化学结构的演化,沉积作用控气的思路对煤储层渗透率非均质性预测具有一定实践意义．     

The current perspective of the PA 1957 gas well pillar study and its implications for longwall gas well pillars

Many states rely upon the Pennsylvania 1957 Gas Well Pillar Study to evaluate the coal barrier surrounding gas wells. The study included 77 gas well failure cases that occurred in the Pittsburgh and Freeport coal seams over a 25-year span. At the time, coal was mined using the room-and-pillar mining method with full or partial pillar recovery, and square or rectangle pillars surrounding the gas wells were left to protect the wells. The study provided guidelines for pillar sizes under different overburden depths up to213 m(700 ft). The 1957 study has also been used to determine gas well pillar sizes in longwall mines since longwall mining began in the 1970 s. The original study was developed for room-and-pillar mining and could be applied to gas wells in longwall chain pillars under shallow cover. However, under deep cover, severe deformations in gas wells have occurred in longwall chain pillars. Presently, with a better understanding of coal pillar mechanics, new insight into subsidence movements induced by retreat mining, and advances in numerical modeling, it has become both critically important and feasible to evaluate the adequacy of the 1957 study for longwall gas well pillars. In this paper, the data from the 1957 study is analyzed from a new perspective by considering various factors, including overburden depth, failure location, failure time, pillar safety factor(SF), and floor pressure. The pillar SF and floor pressure are calculated by considering abutment pressure induced by full pillar recovery. A statistical analysis is performed to find correlations between various factors and helps identify the most significant factors for the stability of gas wells influenced by retreat mining. Through analyzing the data from the 1957 study, the guidelines for gas well pillars in the 1957 study are evaluated for their adequacy for roomand-pillar mining and their applicability to longwall mining. Numerical modeling is used to model the stability of gas wells by quantifying the mining-induced stresses in gas well casings. Results of this study indicate that the guidelines in the 1957 study may be appropriate for pillars protecting conventional gas wells in both room-and-pillar mining and longwall mining under overburden depths up to 213 m(700 ft),but may not be sufficient for protective pillars under deep cover. The current evaluation of the 1957 study provides not only insights about potential gas well failures caused by retreat mining but also implications for what critical considerations should be taken into account to protect gas wells in longwall mining.     

兖州煤田地质构造对瓦斯的控制作用

分析了兖州煤田煤层甲烷赋存特征及地质构造对煤层瓦斯的控制作用，提出应用瓦斯地质理论，加强瓦斯的预测和防治。     

重庆松藻矿区打通一矿M_8煤层瓦斯赋存地质规律

以重庆松藻矿区打通一矿为研究区,基于瓦斯地质理论,探讨了地质构造、煤厚、埋深、有效埋深以及顶底板岩性等地质因素对主采煤层M8煤层中瓦斯赋存的影响规律.通过数理统计的方法构建了各因素与瓦斯含量的回归方程,并对其进行了显著性检验.研究结果表明,煤厚、埋深等是影响打通一矿M8煤层瓦斯含量分布的主控因素,褶皱构造对瓦斯局部富集具有重要影响,而顶底板区域内岩性比较稳定,有利于瓦斯的保存,但不是引起含气性变化的主要因素.