Distinct Fault Style And The Effect On Hydrocarbon Accumulations In Liaozhong Sag

In this paper,the distinct fault style and the effect on hydrocarbon accumulations is taken as the goal,fault structural style is the main line,distinct fault style is the pointcut.Based on the previous analysis of the faults in the Liaozhong sag,combined with the regional geological data,seismic data,oil and gas data,systematically analyzes the distribution characteristics of the fault,the section combination pattern and the multi-period kinematics of the Liaozhong sag,Depth analysis the distinct of fault in Liaozhong sag,and then combined with the mechanism of fault style and the effect on hydrocarbon accumulations and multi-period kinematic differences to explore the factors of fracture control.In this study,the main dissection of Liaozhong fault 1,Liaozhong fault 2,Liaoxi fault 3,in the plane,the three faults directions basically are NE-NNE,Liaozhong 1 fault runs through the Liaozhong sag,Liaozhong fault 2 and Liaoxi fault 3 are not broken to the south of Liaozhong Sag,which control the formation and deposition of Liaozhong sag.In addition to the large trunk fault,the Liaozhong sag is also distributed with many secondary faults.The secondary faults are distributed around the trunk fault,and the plane styles are varied,mainly including geese,bifurcation and so on.In the section,from north to south Liaozhong fault 1dip direction is SE-upright-NW,the structural style is the shovel-type normal fault-flower structure-"y"shape-half flower structure-shovel type normal fault-half flower structure.The Liaozhong fault 2 dip direction is NW-upright-NW,and the tectonic pattern is shovel-type normal fault-negative flower structure-shovel-type normal fault-half-flower structure-inverse"y",The Liaoxi fault 3 dip direction is NW,and the tectonic pattern is shovel type normal fault.In general,the trunk fault broken deep,broken far,broken early;secondary fault broken shallow,broken near,broken late.The faults in the Liaozhong sag are affected by the early extension and the late strike-slip,which mainly experienced the strong fault-off period of the Kongdian Formation and Es~3,the strong fault depression period of Ed3 and Ed2,the reversal period of the end of Ed~1 andNm,the Quaternary strike-slip period,In the strong fault period,the Liaozhong 1 fault are affected by the extension of the fault in the south,The Liaozhong fault 2 Strong fracture in the middle and south,the Liaozhong 1 fault strongly broken in the middle section.The reversal period mainly due to the strike-slip effect,Liaozhong fault 2 local reversal in the middle and south.The strike-slip period the middle of the Liaozhong 1 fault and the middle and north of Liaozhong fault 2right-hand slip.There are also some differences in the oil and gas distribution controlled by the distinct of faults.The oil and gas fields are more in the north section and less in the south section.The distinct of faults also causes the difference of oil and gas accumulation.Formation of shovel-type normal fault control source rock during deposition of the third member of Shahejie Formation in the northern segment.In the middle of the strike-slip fault,the strike-slip activity during the Nm depositional period and the flower-like structure formed by the strike-slip action control the scale and location of oil and gas accumulation.The reverse structure at the end of the Dongying Formation in the southern section provides traps for oil and gas.