塔里木盆地塔中隆起及北围斜区断裂体系与油气成藏关系

笔者探讨了断裂在油气聚集中的作用,它是制约塔中隆起及北围斜区油气分布规律的关键因素。基于地震资料断裂解析,塔中隆起及北围斜区断裂体系主要由北西—南东延伸的压扭性断裂带与北东—南西延伸的走滑断裂构成。断裂体系主要形成于中晚加里东中期,此后经历了晚加里东、晚海西和喜山期的继承性活动与改造。中加里东中期构造是该区构造的主要定型期,断裂不仅控制了构造带发育,也是风化壳岩溶储层、礁滩相储层、热液溶蚀碳酸盐岩储层形成关键因素。断裂带后期活动为油气运聚提供了通道,北北东断裂是油气由北部坳陷向隆起长距离运聚的主要通道。断裂带的复杂性造就了研究区油气具有沿断裂带分布,成藏模式多样,差异富集特征。

Relationship between fault system and reservoir formating in Tazhong uplift and north slope area in Tram Basin

The effection of faults in oil ＆ gas accumulation was a key factor for oil ＆ gas exploration in Tazhong uplift and north slop area surrounded.Based on the interpretation of the seismic data we concluded that fault systems in Tazhong uplift and its north slope area were developed in middle Caledonan.The NW-SE compression-shear faults and NNE-SSW strike-slip faults made up the fault systems.The fault systems underwent four staged tectonic movements,including the middle Caledonan,late Caledonan,late Hercynian,and Yanshan-Hercynian.It is mainly developed in middle-middle Caledonan.The faults mainly controlled the form of the structural zone and the form of the carbonate reservoirs including the Karst-,reef-and hot fluid in type.The late movements of the faults provided the main oil migration pathway.NNE faults are the long-distance migration pathway which caused the oil and gas from north depression migrate to the Tazhong uplift.All these result in the oil reservoir distributed along the fault belts and the various oil accumulation modes.