陕西省定边-吴起地区延长组长8地层裂缝形成因素分析  

Analysis of factors affecting fractures of Chang-8 subsection based on Dingbian-Wuqi area of Shaanxi province

作　　者：马海勇[1] 周立发[2] 张雪峰[3] 韩天佑[3] 

机构地区：[1]西安科技大学地质与环境学院,陕西西安710054 [2]西北大学地质学系,陕西西安710069 [3]中国石油长庆油田公司勘探开发研究院,陕西西安710018

出　　处：《陕西师范大学学报（自然科学版）》2016年第2期106-110,共5页Journal of Shaanxi Normal University：Natural Science Edition

基　　金：国家科技重大专项基金(2011ZX05044;2011ZX05001-004);西安科技大学博士启动基金(A5030740)

摘　　要：根据岩心观察、薄片分析和成像测井解释等相关资料,结合区域构造演化史,对陕西省定边-吴起地区延长组长8段裂缝的分布特征及成因进行分析。研究表明:水平构造挤压应力是形成裂缝的主要力源,定边-吴起地区在燕山期NWW—SEE向挤压应力产生了E—W向和NW—SE向裂缝,喜山期NNE—SSW向挤压应力产生了N—S向和NE—SW向裂缝。受沉积相作用,储层非均质性抑制了共轭剪切裂缝系中NW—SE、N—S向裂缝的发育,使E—W、NE—SW向裂缝较发育;靠近伊陕斜坡浅水三角洲河道侧翼E—W向裂缝发育,天环坳陷轴部附近NE—SW向裂缝较发育。现今NEE—SWW向地应力影响不同组系裂缝的地下张开度、连通性和渗透性,对储层勘探与开发井网部署起着重要的作用。Based on the characteristics of tectonics evolution,the well drilling,log information and microscopic,high resolution boreholemicro resistivity image logs（FMI）,the flat distribution regulation and genesis of the fractures of Chang-8subsection of Yanchang Formation in DingbianWuqi area of Shaanxi province were analyzed.The research showed that the horizontal compression stress formed the fractures.The E—W and NW—SE regional fractures were formed by the horizontal compression stress of NWW—SEE orientation during the Yanshanian movement,the NE—SW and N—S fractures were formed by the horizontal compression stress of NNW—SEE orientation during the Himalayan movement.Affected by the influences of the strong terrane anisotropism made by sedimentary and diagenesis,the development of two sets of conjugate shear fractures at the same time was different in the dissimilar sedimentary system,NW—SE and E—W shear fractures would develop well,NW—SE and N—S fractures was restrained.It is found that E—W fractures developed well where closed to Yishan slope,and NW—SE fractures developed well neared Tianhuan depression or faults.The directions of the present tectonic stress fields in the basin were NEE—SWW which controlled the fracture connectivity and permeability.It is very important to exploration and the oilfield network arrangement of low-permeability oil.

关 键 词：定边-吴起地区 延长组 成像测井 裂缝 沉积相 

分 类 号：TE121[石油与天然气工程—油气勘探]