淮北地区煤储层物性及煤层气勘探前景

研究了淮北地区地物构造演化及控气特征,结果认为：淮北地区印支期以来的构造演化对煤储层物性控制作用十分显著,以EW向的宿北断裂为界,北部地区煤层气勘探前景不佳,南部地区的东部,煤层的展布受褶皱形态的控制。在宿面向斜和南坪向斜中,煤层埋深、煤体结构、含气性、含气量和渗透率等储层物性均有利于煤层气的运移、聚集和保存,具有较好的煤层气勘探前景;临涣矿区强变形构造煤发育,煤体结构复杂,基本无勘探前景;涡阳矿区正断层发育,煤层气含量相对较小,但渗透性较好,值得进一步深入研究。     

沁水盆地郑庄区块构造演化与煤层气成藏

基于沁水盆地郑庄区块的构造发育特征,研究了自二叠纪煤系形成以来该区域构造应力场演化,分析了其对煤层气藏的控制作用,包括构造-埋藏史、后期成藏演化及成藏控制因素.研究表明:郑庄地区主要经历了印支期、燕山期、喜马拉雅早期和喜马拉雅晚期—现代4个期次的构造应力场演化.在构造控制下,二叠纪煤层经历了印支期和燕山中—晚期两次成烃作用,特别是燕山中、晚期煤层生气量巨大,是煤层气的主要成藏期.此后,随着地壳持续抬升剥蚀,煤层埋藏不断变浅,并发育了多组封闭性较好的节理.受南东侧的寺头断层控制,煤层埋深处于600～1 200m,为煤层气成藏以来的最浅埋藏,虽然本区二叠系煤层气的成藏时间较早,但保留的煤层气含量大,煤储层厚度大,且煤层埋藏适中.     

海孜煤矿构造变形及其对煤厚变化的控制作用

分析了海孜煤矿岩、煤层组合特征 ,总结了 7,8,9,1 0煤层的断层、层滑构造和煤厚变化情况 ,探讨了断层与层滑构造的形成机制以及构造变形对煤厚的控制作用 .结果表明 :7,8,9,1 0煤层等软弱层属于塑性层 ,而各煤层及顶底板岩层组合及构造变形又有较大区别 .在多期构造应力场作用下 ,7,8,9煤层以层滑构造发育为主 ,形成煤层急剧增厚变薄带 ,并见压剪和张剪性两种层间断层 ;1 0煤层以中小型剪切式断层为主 ,层滑构造发育程度次之 ,煤厚变化幅度较小 .断层和层滑构造又存在密不可分的组合关系     

河东煤田乡宁地区主煤层储层物性特征及意义

通过煤矿井下观察及室内测试，对研究区晚古生代煤系主要煤储层的物性特征及煤层气勘探开发前景进行了分析．结果表明：主要煤储层中割理较为发育，割理面以ＮＷ走向为主，且多为紧闭；孔隙率较高，孔比表面积主要分布于孔径较小的微孔和过渡孔段，孔隙的连通性较差，煤层渗透率极低；主要煤储层的含气性总体上较差，可能与喜山期的拉张应力作用有关，具有煤层气勘探开发前景的地区可能处于区内西北部的煤层深埋区及区内次级向斜等构造有利部位．     

南桐矿区警构造对破坏煤发育的控制

在详细研究南酮矿区破坏煤发育规律的基础上，论述了矿区构造对破坏煤发育的控制。具体表现在以下几个方面：（1）构造应力是造成煤层破坏的直接因素；（2）破坏煤是构造运动过程中压剪变形的产物，是构造演化过程中逐渐形成的；（3）煤层厚度、煤层在煤系剖面中的位置、煤层倾角和断裂发育情况控制了破坏煤的横向和纵向变化，其它因素的影响居次要地位。     

柴达木盆地北缘断裂构造变形特征

分析了柴达木盆地区域构造背景，研究了柴达木盆地北缘断裂构造的宏观及微观变形特征及不同方向、不同组合的断裂构造特征．断裂走向主要为NWW和NEE向，与区域构造线的展布方向具有较好的一致性．这些断裂构造基本以挤压逆冲性质为主，形成了具有不同结构特征的逆冲推覆构造．断裂构造往往具有多期叠加变形的特征．．不同时期构造应力作用方向和性质基本一致，反映了近NS向挤压应力的长期和持续作用，但不同变形期应力作用的强度和断裂的变形环境存在一定差异．     

河南省下二叠统山西组二_1煤煤层气储层描述

从煤厚、煤岩组成、煤级、煤体结构、裂隙系统、渗透性、吸附／解吸特性等方面对河南省的主可采煤层二１煤的煤层气的储层特征进行了详细论述．指出镜质组含量较高、割理比较发育、外生裂隙发育适中的原生结构煤和碎裂煤渗透性最好,是最有利的储层;外生裂隙发育适中的无烟煤是有利储层;碎粒煤为不利储层;糜棱煤为不可开发储层．临界解吸压力较高、含气量较高的中煤级煤分布区是煤层气勘探开发的首选地区．     

煤层气储层渗透性研究进展

煤储层渗透性是制约煤层气勘探选区的重要参数,影响渗透率差异分布的因素有很多,从裂隙系统的发育、煤储层有效应力、煤层构造演化、煤岩变质程度几个方面阐述了它们与高渗区空间分布的关系及其研究进展.对其研究技术、手段、主要认识及存在的问题等进行了系统的总结.对有效预测煤储层渗透性、发展渗透性描述理论、寻找有利勘探区带具有重要意义.     

“平顶山八矿、十矿煤层气综合开发利用与煤矿瓦斯灾害治理”通过鉴定

由我院苏现波副教授等与平顶山煤业(集团)有限责任公司合作完成的科研课题“平顶山八矿、十矿煤层气综合开发利用与煤矿瓦斯灾害治理”于2000年12月通过了由河南科学技术厅组织的科技鉴定． 　　1.在区域地质研究的基础上,对八矿、十矿主采煤层进行了煤层气资源评价． 　　2.从煤中裂隙、煤体结构及其发育规律、煤储层渗透性、储层压力、储层温度、吸附特征、煤岩层力学性质等方面对煤层气储层进行了详细评价． 　　3.对已有勘探、生产阶段的含气量资料进行了筛选,并根据储层压力和兰氏方程对无直接测试资料的地区进行了含气量预测。 　　4.为避免煤层气顶板强化工艺实验室模拟试验的局限性,结合生产需求,直接在现场进行了试验。在八矿、十矿进行了井下高位钻孔抽放瓦斯的试验． 　　5.首次系统地确立了煤层气综合开发工艺的选择原则,提出了“区别对待、综合配套、优化组合”的总体思路。 　　6.首次提出了在碎粒煤、糜棱煤发育的高瓦斯突出煤层,试行“顶板强化”的特殊地面煤层气开发工艺,解决了国内外迄今为止未解决的在构造煤发育区高瓦斯突出煤层,进行煤层气资源开发和瓦斯灾害治理的高难技术问题     

白额地区2~#煤层气藏成藏控制因素分析

在分析白额地区2^#煤储层空间发育特征、储层物性特征、含气量分布特征及区域构造背景的基础上,对煤层气成藏控制因素进行分析。结果表明：构造演化史直接控制着煤储层埋藏史及生烃史,是煤层气成藏主控因素;地下水水动力特征和围岩封闭特征决定了煤层气藏的保存条件,是煤层气成藏的关键;综合以上特征,可以得出2#煤煤层气藏为单斜-水动力封堵型煤层气藏。     

Coal reservoir characteristics and their controlling factors in the eastern Ordos basin in China

In the eastern Ordos basin, due to the diversity of the tectonic setting, coal rank, gas content and permeability, coal reservoirs have differing characteristics. In this paper, based on coal reservoir geometry, gas content, adsorption capacity, pores and fissures developments and permeability data, the coalbed methane(CBM) reservoir characteristics and their controlling factors in the eastern Ordos basin is discussed. The results show that, due to undergoing different paleo-temperatures in the geological history,coal rank has a higher trend from the north part to the south and from the shallow part to the inward basin, which determines CBM distribution and recoverability. In the north, although having large coal thickness and high permeability, Zhungeer-Xingxian coal rank is low, and gas content is small. In the central part, with medium rank, higher gas content and relatively high permeability, and the Wubao-Liulin area is the most favorable area in the eastern Ordos basin. In the southern part, medium and high metamorphism coal occurs, and although having the highest gas content, the permeability in the Hancheng area is low due to the development of sheared coal.     

沁水盆地构造演化及其对游离气藏的控制作用

应用平衡剖面法和埋藏史分析法,对沁水盆地构造演化特征及游离气成藏条件进行了研究,分析了构造演化对游离气藏的作用,建立了沁水盆地游离气聚集模式图。燕山期,在地壳上升的过程中,先期形成的煤层气通过裂缝游离出来在顶板砂岩的低应力区聚集,富集在褶皱的翼部。到了喜山期,由于应力方向的改变,对先期形成的褶皱进行了轻微的改造,使得先期富集的游离气发生再次运移,聚集的部位发生了一定的改变,但是总体仍然以远离断裂的中高部位为主。     

吐哈盆地沙尔湖地区煤层气钻完井适用技术探讨

在剖析美国圣胡安盆地煤层气空气钻井、裸眼洞穴完井技术及优势的基础上,确定了低煤阶煤层气钻井及裸眼洞穴完井的煤储层条件等,并以吐哈盆地沙尔湖地区低煤阶煤层气为主要研究对象,利用类比法及地质统计法,具体分析了吐哈盆地沙尔湖地区的煤储层厚度、含气量、渗透率、井壁稳定性及储层压力条件等．研究表明,沙尔湖地区煤层厚度大,储层物性好,井壁稳定性好,可采用低成本空气钻井及裸眼完井技术提高钻井效率,保护煤储层,提高煤层气采收率．     

Prediction of coal structure using particle size characteristics of coalbed methane well cuttings

Severely deformed coal seams barely deliver satisfactory gas production. This research was undertaken to develop a new method to predict the positions of deformed coals for a horizontal CBM well. Firstly, the drilling cuttings of different structure coals were collected from a coal mine and compared. In light of the varying cuttings characteristics for different structure coals, the coal structure of the horizontally drilled coal seam was predicted. And the feasibility of this prediction method was discussed. The result shows that exogenetic fractures have an important influence on the deformation of coal seams. The hardness coefficient of coal decreases with the deformation degree in the order of primary structural, cataclastic and fragmented coal. And the expanding-ratio of gas drainage holes and the average particle size of cuttings increase with the increase of the deformation degree. The particle size distribution of coal cuttings for the three types of coals is distinctive from each other. Based on the particle size distribution of cuttings from X-2 well in a coal seam, six sections of fragmented coal which are unsuitable for perforating are predicted. This method may benefit the optimization of perforation and fracturing of a horizontal CBM well in the study area.     

刘家勘探区煤储层特征及煤层气开发条件研究

研究了刘家勘探区煤储层特征及煤层气开发条件，认为研究区煤储层的煤级，孔隙性和渗透性相对较低，但地质构造简单，煤层气资源丰度高，煤储层厚度，含气量，含气饱和度，甲烷浓度，临储压力比，临界解吸压力等都较高，压力梯度基本正常，可采性以及煤层气开发和利用前景条件较好。并已被煤层气井排采试验结果所初步证实，同时，中也就区内今后的煤层气开发工作提出了某些建议。     

非低阶煤煤层气解吸关系研究

煤层气解吸作用的研究可较好地预测产气量和气量持续周期。对当前数个煤层气勘探开发较为活跃地区的煤进行了吸附解吸实验,通过对实验数据拟合分析,得到煤层气降压解吸服从数学模型Vd=adbdp/1+bdp+c。在煤层气井排水降压产气过程中,采用此模型对煤层气的解吸量进行计算,揭示了降压解吸滞后是由于剩余含气量c的存在,解吸量ad与最大含气量amax线性相关,最大解吸率为c/amax,生产上要提高解吸量只能通过改变吸附系统吸附热与解吸速率。通过2口直井与2口水平井的排采实践对本文研究结论进行了验证。     

Reservoir reconstruction technologies for coalbed methane recovery in deep and multiple seams

Multiple coal seams widely develop in the deep Chinese coal-bearing strata. Ground in situ stress and coal seam gas pressure increase continuously with the increase of the mining depth, and coal and gas outburst disasters become increasingly severe. When the coal is very deep, the gas content and pressure will elevate and thus coal seams tends to outburst-prone seams. The safety and economics of exploited firstmined coal seams are tremendously restricted. Meanwhile, the multiple seams occurrence conditions resulted in different methane pressure systems in the coal-bearing strata, which made the reservoir reconstruction of coal difficult. Given the characteristics of low saturation, low permeability, strong anisotropy and soft coal of Chinese coal seams, a single hydraulic fracturing surface well for reservoir reconstruction to pre-drain the coalbed methane(CBM) of multiple seams concurrently under the different gas pressure systems has not yet gained any breakthroughs. Based on analyses of the main features of deep CBM reservoirs in China, current gas control methods and the existing challenges in deep and multiple seams, we proposed a new technology for deep CBM reservoir reconstruction to realize simultaneous high-efficiency coal mining and gas extraction. In particular, we determined the first-mined seam according to the principles of effectiveness and economics, and used hydraulic fracturing surface well to reconstruct the first-mined seam which enlarges the selection range of the first-mined seam. During the process of mining first-mined seam, adjacent coal seams could be reconstructed under the mining effect which promoted high-efficiency pressure relief gas extraction by using spatial and comprehensive gas drainage methods(combination of underground and ground CBM extraction methods). A typical integrated reservoir reconstruction technology, ‘‘One well for triple use", was detailed introduced and successfully applied in the Luling coal mine. The application showed that the proposed technology could effectively promote coal mining safety and simultaneously high-efficiency gas extraction.     

鄂西渝东区上古生界构造型式及对石炭系勘探认识

鄂西渝东区海相地层经历了多期构造运动 ,受到过多种应力场作用 ,因应力条件、介质条件和边界条件差异 ,形成了现今比较复杂的构造面貌。纵向上 ,因上、下构造变形层抗应变能力的不同 ,在挤压应力作用下发生差异形变 ,产生纵向变异 ;横向上 ,形成了隆凹相间的区域构造面貌。本文根据鄂西渝东区区域和局部构造特征、构造型式、展布规律 ,论述了古、今构造对本区油气运移和聚集的控制作用 ,指出本区石炭系勘探的有利区带及目标。