基于生长断层活动性的定量评价、大量流体包裹体的光性特征和均一温度结合单井埋藏史等综合分析,对南堡凹陷断层活动与油气成藏和富集的关系进行研究.结果表明:除两条边界断层外,南堡凹陷切穿烃源岩层系且在明化镇期活动的断层总计45条；沙河街期至东营期断层活动性增强,馆陶期为相对静止期,在明化镇期断层活动性再次增强,断层停止活动时间主要为距今7～2.5Ma,平均距今4 Ma.根据明化镇早期断距的大小和断层停止活动时间,将45条断层划分为A、B、C3类,油气主要富集在活动性相对较强、断层停止活动时间相对较晚的A、B两类断层附近的有利圈闭中.根据流体包裹体均一温度结合埋藏史得出研究区油气成藏期最晚时间主要为距今5～1Ma,平均距今2 Ma,晚于断层停止活动时间2 Ma;断层停止活动后,当上覆地层沉积厚度为180 ～300 m时,其在垂向上的通道逐渐闭合.%The relationship between fault activity and hydrocarhon accumulation and enrichment in Nanpu depression was studied by the technologies of quantitative evaluation on fault activity and large amount analyses of microscopic fluorescence, homogenization temperatures of fluid inclusions and burial history. The results show that besides 2 boundary faults, there are 45 growth faults which cut source rocks and are active in the phase of Minghuazhen formation. From the phase of Shahejie formation to Dongying formation, the fault activity is increased. The faults is relative inactive in Cuantao formation. In the phase of Minghuazhen formation, the fault activity is increased again. The inactive phase of the faults is mainly in 7-2.5 Ma, 4 Ma in average before present. According to the fault throw in early stage of Minghuazhen formation and inactive phase of the faults, the 45 faults are divided into 3 types named A, B and C. Hydrocarbon distribution is mainly enriched in the favorable traps near type A and type B faults which are relative more active and whose inactive phases are later. The phase of reservoir forming stage is mainly in 5 - 1 Ma, 2 Ma in average before present based on the analyses of homogenization temperatures of fluid inclusions and buried history of wells, which is 2 Ma later than the time of the faults ceasing. After the faults activity ceases, the overlying sedimentary depth is about 180-300 m, and their vertical pathways are gradually closed.
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