In recent years, the exploration and exploitation of unconventional natural gas in coal-bearing strata is highly noticed by do-mestic and foreign scholars. Porosity and permeability of coal-bearing reservoir in eastern Ordos Basin are rather low, while the devel-opment of structural fracture can provide reservoir space and seepage channel for this kind reservoirs. Taking the Taiyuan and Shanxi formations in the Linxing block as example, has carried out prediction of tectonic stress field during the fracturing period and its con-trolled and developed fissures. The result has shown: vertically, structural fractures in Taiyuan Formation are rather well developed with fracture density within 0.165~0.290m-1 extent;fracture porosity relatively higher, between 1.2%~6.78%. On plane, has presented a high in south and low in north distribution pattern as a whole. Based on study area tectonic stress field evolution, structural fracture development and distribution relations, have considered that the effective structural fractures were mainly formed during the Yansha-nian stage, their development degree and distribution pattern mainly controlled by faults and Zijinshan uplift in south. The study can provide reference and basis for coal measures"three gases"*integrated exploration assessment and exploitation target selection in the area.%近年来,含煤地层非常规天然气的勘探开发受到国内外学者高度关注.鄂尔多斯盆地东缘地区含煤储层孔隙度和渗透率较低,构造裂缝的发育可为该类储层提供储集空间和渗流通道.以临兴区块太原组和山西组为例,对主要造缝期的构造应力场及其控制发育的构造裂缝进行预测.结果表明:纵向上,太原组的构造裂缝较为发育,其裂缝密度为0.165~0.290条·m-1,该组的裂缝孔隙度也相对较高,为1.2%~6.78%;平面上,总体呈南高北低展布格局.基于研究区构造应力场演化和构造裂缝发育、分布关系,认为有效构造裂缝主要形成于燕山期,其发育程度和分布规律主要受控于断层与南部紫金山隆起.该区研究成果,可为本区煤系"三气"综合勘探评价及开发选区提供参考依据.
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