珠江口盆地X区块断裂系统特征及其对油气成藏的作用

Characteristics underlying fault system in block X of Pearl River Mouth Basin and its effect on hydrocarbon accumulation

为研究珠江口盆地X区块断裂系统对油气成藏的影响,在精细构造解释基础上,运用断层几何学、运动学等方法,研究X区块断裂系统特征。研究结果表明:X区块平面上发育NEE、NW走向两组断层,断层组合以平行式、斜列式为主;剖面上断层以多米诺式、复杂半地堑构造样式为主;晚期断层形成时间与烃源岩大量生排烃时间较为匹配;距离生烃中心越远,油气发育层位越浅,反之,油气发育层位越深,油气通过控洼边界断裂、不整合等主要疏导体系,近源成藏。

This paper aims to study the influence of fault system in block X of Pearl River Mouth Basin on hydrocarbon accumulation.The study building on fine structural interpretation investigates the characteristics of fault system using fault geometry and kinematics.The results show that two groups of NEE and NW trending faults are developed in block X,and the fault combination is mainly parallel and oblique;The faults on the section are dominated by domino and complex half graben structural style;the time of late fault formation is relatively matched with the time of massive hydrocarbon generation and expulsion of source rocks;the three-dimensional oil and gas migration and accumulation simulation finds that the farther away from the hydrocarbon generation center,the shallower the oil and gas development horizon;the closer it is to the hydrocarbon generation center,the deeper the oil and gas development horizon;and oil and gas are formed near the source due to the main dredging systems such as depression controlling boundary faults and unconformities.