准噶尔盆地车排子凸起西翼断裂特征及其控藏作用

摘要

通过对地震和测井资料的分析,认为车排子凸起西翼存在深浅两套断裂系统,大致以古近系顶部不整合为界,深层断裂系统发育逆断层,浅层断裂系统发育正断层,且断裂形成分为3个期次,深层断裂影响浅层断裂的发育,控制了中生界的沉积.断槽内侏罗系砂体和断裂是油气运移的重要通道.通过对断裂封闭性的分析,认为车排子凸起西翼的浅层正断层在沙一段主要起输导作用,在沙二段对油气起遮挡作用,深层逆断层在侏罗系主要起输导作用.根据对断裂控藏作用的分析,认为车排子凸起西翼不同位置断裂的控藏作用具有差异性,断裂控制了圈闭的有效性,同时为油气运移提供通道,沟通深、浅层油气,控制了油气的分布.根据断裂封闭性分析结果,结合油气显示和断裂控藏作用,认为车排子凸起西翼油气运移存在3个方向.%With analysis on the seismic and well logging data,it is thought that two sets of deep and shallow fracture systems,divided by the unconformity boundary on the top of Paleogene,are developed in the west wing of Chepaizi uplift,with reverse faults developed in the deep and normal faults in the shallow part.The fractures were formed in three stages.The deep fractures control the development of the shallow fractures as well as the Mesozoic deposition.The Jurassic sand bodies and fractures in the fault trough are important pathways for oil-gas migration.According to the sealing ability analysis,the shallow normal faults serve as the main transport pathways in S1 member but the barriers in S2,while the deep reverse faults are mainly carriers in Jurassic.Fractures in different positions also differ in reservoirforming control functions.The faults control the effectiveness of entrapment,provide migration pathways and connect oil-gas resources between deep and shallow,thus control the distribution.Based on the analysis above,it is concluded that there are three oil-gas migration pathways in the west wing of Chepaizi uplift.