川西须家河组致密碎屑岩裂缝分布规律与影响因素分析  

Analysis of Distributing Law and Influencing Factors of Compact Clastic Rock Fracture in Xujiahe Formation in West Sichuan Region

作　　者：徐炳高[1] 李阳兵[1] 葛祥[1] 吴见萌[1] 

机构地区：[1]中国石化集团石油工程西南有限公司测井分公司,四川成都610100

出　　处：《测井技术》2010年第5期437-441,共5页Well Logging Technology

摘　　要：川西须家河组成藏对裂缝有强烈的依赖,裂缝的识别与评价是储层评价的基础和评价的难点。利用成像测井提取信息计算了裂缝密度、裂缝长度、裂缝的平均水动力宽度、裂缝视孔隙度等参数;建立了综合评价指标——裂缝强度;开展了裂缝展布规律研究,纵向上裂缝主要分布于须家河组二段,须四段发育程度较差;横向上,裂缝强度高值区主要分布于构造轴部,方向以近东西向为主。通过裂缝影响因素分析,认为刚性强度大、交错层理不发育的块状砂岩易于形成高角度裂缝;构造轴部、南北向断裂密集分布区以及断裂形变明显变化区域为有利的裂缝发育区。根据这些特点,提出了裂缝预测基本思路和方法。Hydrocarbon accumulation strongly depends on the degree of fracture developments in Xujiahe formation of Western Sichuan region, fracture recognition and evaluation are not only a basic work in reservoir evaluation, but also a difficult point of reservoir evaluation. In view of this, based on the log data processing and micro-resistivity images, calculated are fracture density, fracture length and fracture hydrodynamic width, and fracture apparent porosity, and then the index of fracture strength is built. Based on the index of fracture strength and through the research on fracture distributing law, we think that the fractures are distributed in the second member of Xujiahe formation in vertical, and the degree of fracture developments in the fourth member of Xujiahe formation are weaker. Horizontally, the high value area of degree of the fracture developments is distributed in the axis of the structure, the direction is maily EW. Through the research on affecting factors of fractures, the comprehensive evaluation show that massive sandstone of high stiffness index and undeveloped cross bedding form high angle fracture easily. The axis of the structure, the dense SN braakage belt and the deformation belt of the fractures are the favorable area for fracture development zones. According to the characteristics, thoughts and methods of fracture prediction are proposed.

关 键 词：测井解释 裂缝强度 裂缝分布 裂缝预测 须家河组 川西 

分 类 号：P631.84[天文地球—地质矿产勘探]