摘要
受L断裂带左旋走滑应力及Z火成岩体多期活动的综合影响,A区块断裂系统复杂。基于应力叠加程度的不同,研究区发育火山作用型和区域应力型2类断层。火山作用型断层主要伴随Z岩浆侵入热事件形成,对气藏起调整过度的作用,破坏天然气成藏;区域应力型断层主要由L断裂带左旋应力场派生出的3类断层组成,分别为NW向张性走滑断层、NE和近SN向压性走滑断层及X型共轭剪切破裂断层,通过对钻井距断层横向距离、砂岩厚度及气层厚度之间关系分析,认为该类断层对横向范围2 km之内起适度调整的作用,而远离断层控制范围,对气藏调整的作用不足。可见断层输导能力对致密气的纵向分布以及断层对储层物性的改造对致密气藏的横向展布均起到了重要的控制作用,打破了一直以来沉积作用控制致密气成藏的局限认识,因此明确断层的成因机制及控藏作用对鄂尔多斯盆地东北缘上古生界致密气的勘探开发具有关键现实意义。
The faults in the block A of Northeast Ordos Basin are divided into two types,i.e.volcanic activity related faults and regional stress related faults,according to their origin.The volcanic activity related faults by Z magmatism destroy gas accumulations.However,the regional stress related faults,which are influenced by L sinistral strike-slip and composed of northwest tensional strike-slip faults,northeast and near north-south compressional strike slip faults and X type conjugate shear fracture faults,are favorable to gas accumulation.Within a radius of 2 kilometers surrounding the regional stress related faults,gas can get better accumulated.These research results challenged the old view point that the sedimentation was the only influence factor in tight gas accumulation.It means that fault genetic mechanism and its controlling over gas accumulation possess plays key roles in oil accumulation and have great significance to the exploration and development of the Upper Paleozoic tight gas in northeast Ordos Basin.
作者
张璐
祝彦贺
李林涛
黄众
杨小峰
ZHANG Lu;ZHU Yanhe;LI Lintao;HUANG Zhong;YANG Xiaofeng(CNOOC Research Institute,Beijing 100028,China;CNOOC International Limited,Beijing 100028,China)
出处
《海洋地质前沿》
CSCD
2020年第3期57-64,共8页
Marine Geology Frontiers
基金
国家重大专项(2016ZX05027-003-003).
关键词
鄂尔多斯盆地
A区块
断层特征
左旋应力场
岩浆活动
控藏作用
Ordos Basin
block A
minor faults
sinistral shear stress field
magmation
controlling of gas accumulation
