基于分形理论的煤层微观裂隙复杂程度评价  

Fractal theory-based evaluation of complexity of coal micro-fracture

作　　者：杜志立[1] 王继尧[1] 方俊华[1] 叶骏[1] 

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221008

出　　处：《黑龙江科技学院学报》2010年第4期251-255,共5页Journal of Heilongjiang Institute of Science and Technology

基　　金：国家重点基础研究发展规划(973)项目(2009CB219605)

摘　　要：为定量描述煤层和上覆岩层微观断裂网络的复杂程度,以鄂尔多斯盆地大宁—吉县地区为例,借助显微镜和显微光度计分析其微观裂隙的发育规律;根据分形几何原理,采用改进的网格覆盖法,计算其微观裂隙分形维数。结果表明:该区煤层上覆岩石裂隙发育不大,连通性不强,有利于煤层气的储存;煤层裂隙较为发育,但闭合及充填的较多,不利于煤层气的运移;8#煤层的微观裂隙发育程度及均匀性总体上比5#煤层略高;岩层微观裂隙主要发育在午城、瑶曲和管头附近;同一位置的煤层与岩层的微观裂隙复杂程度呈负相关。该结果为进一步研究该区煤层气地质条件提供了依据。This paper presents the quantitative description of the complexity of micro-fracture network of the coal and overlying strata, the analysis of the development of law micro-cracks with the help of mi- croscopes and microscope photometer, as in the case of the Ordos Basin, Daning-Jixian area, and the calculation of the fractal dimension of micro-cracks, based on the principles of fractal geometry and the improved grid covering method. The results show that the overlying strata of coal bed, with poorly devel- oped rock fractures and poor connectivity, is favourable to the storage of CBM, coal beds show more de- veloped cracks, which are closed or filled in larger numbers, thus hindering the transport of CBM. In general, 8# coal seam has a slightly better developed and uniform micro-cracks than 5# coal seam, the rock micro-cracks of overlying strata are found to be developed mainly near Wucheng, Yaoqu and Guan- tou. There is a negative correlation in terms of the complexity of the micro-crack between the coal and o- verlying strata has in the same position. The results provide a basis for the further research on geological conditions of CBM in the area.

关 键 词：煤层 微观断裂网络 复杂程度 分形理论 信息维 

分 类 号：P618.11[天文地球—矿床学]