川东宣汉地区飞仙关组裂缝特征及成因研究

根据全直径岩芯、 薄片鉴定等资料， 对宣汉地区飞仙关组裂缝特征进行了分析， 并利用常规测井资料对该区井剖面裂缝发育情况及纵向裂缝可能的分布情况进行了研究， 在此基础上结合川东地区地质特征，对研究区裂缝成因进行了深入研究。研究结果表明： 飞仙关组中下段主要发育有垂直构造裂缝、 水平裂缝、斜交裂缝及成岩期形成的裂缝； 裂缝主要有构造裂缝与非构造裂缝两类， 构造裂缝成因主要包括与断层构造有关的裂缝、 与褶皱构造有关的裂缝及与弱变形构造区有关的裂缝， 力学成因主要有剪切裂缝、 扩张裂缝和拉张裂缝 3 种基本类型； 非构造裂缝主要成因可分为成岩裂缝、 溶蚀裂缝、 收缩裂缝、 表生裂缝。生产实践表明， 任何一种裂缝在碳酸盐岩储集层中均是重要的储集空间及渗流通道。

The Study of Fracture Characteristics and Causes at Feixianguan Formation inXuanhan Area of Eastern Sichuan

The fracture characteristics of Feixianguan Formation in Xuanhan area were analyzed by whole diametercore observation and thin section analysis information， and the growth state and longitudinal distribution of frac-tures were studied from conventional logging data at every well； Based on ahead of analysis， fracture genesis wasresearched deeply through combined with geological structures in east of Sichuan. The results show that verticaltectonic， horizontal， diagonal and diagenesis fractures mainly develop at the lower of Feixianguan Formation； thereare two kinds of fracture that is tectonic and non-tectonic， and tectonic fracture is associated with faults， drape andweak deformation areas， which has three kinds of mechanical causes， which are shear fractures， expansion fracturesand tensile fractures. Non-tectonic fractures can be divided into four kinds， which are diagenetic fracture， corrosionfracture， shrinkage fracture， supergene fracture. The production practice indicates that any fracture in carbonatereservoirs is important in both storage space and the flow channel.