塔里木盆地顺托果勒低隆起顺托1井区油气成藏模式

Hydrocarbon accumulation mode of Shuntuo 1 well block in the Shuntuoguole lower uplift,Tarim Basin

塔里木盆地顺托1井区奥陶系碳酸盐岩与志留系碎屑岩层系均获得油气流,为受同一条断裂沟通的2套油气藏,但2套油气藏的地层温度、地层压力系数与油气性质均存在较大差异。通过油气性质、饱和烃色谱、饱和烃色谱—质谱、芳烃色谱—质谱与同位素等地球化学特征对比分析,认为两者为油源相同、多期充注、相互关联的2套油气系统。结合断裂活动期次、断裂活动强度、油气垂向分布特征、油气运移方向及油气充注期次研究,进一步明确志留系油藏主要成藏期为海西晚期,而奥陶系凝析气藏主要成藏期为喜马拉雅期。主要成藏时期断裂的活动强度决定了该区油气富集层系,并初步建立了该区"垂源与侧源供烃、断层垂向输导、断裂活动强度控层、下部圈闭优选聚集"的油气成藏模式。

Oil and gas were acquired from the Ordovician carbonate and the Silurian clastic rocks of Shuntuo 1 well block in the Tarim Basin. The two reservoirs were in communication via a fault,but their temperature,pressure coefficient and oil and gas properties are different. By analyzing their geochemical characteristics（ GC of saturated hydrocarbons,GC-MS of saturated and aromatic hydrocarbons and isotopes） we determined that the two reservoirs are different oil and gas systems,which have the same oil source,experienced multiple stages of filling,and are correlated with each other. Combined with the research of fault activity timing and intensity,oil and gas vertical distribution,migration direction and charging period,we confirmed that the main forming stage of Silurian reservoir was in the late Hercynian,and the condensate gas reservoir in the Ordovician was formed during the Himalayan period. Fault activity intensity during the main accumulation period determined hydrocarbon accumulation strata and oil and gas properties in the area. We established a hydrocarbon accumulation mode of ＂hydrocarbon supply of vertical and lateral sources,vertical migration by faults,controlling layer by fault activity intensity,and optimal aggregation in lower traps＂.