松辽盆地宋站南地区扶杨油层运聚成藏机制及主控因素

通过油藏解剖和油成藏条件空间配置关系，对宋站南地区扶杨油层油运聚成藏机制和主控因素进行了研究，得到宋站南地区扶杨油层油主要来自青一段源岩。油源区内扶杨油层油运聚成藏模式为:三肇凹陷青一段源岩生成的油在超压作用下通过T2源断裂向下“倒灌”运移进入扶杨油层后，再在浮力作用下沿断裂向高断块圈闭进行短距离的运聚成藏。油源区外扶杨油层油运聚成藏模式为:三肇凹陷扶杨油层中的油在浮力作用下沿被断裂沟通的砂体侧向运移至宋站南地区，在断层上升盘圈闭中聚集成藏。油源区内扶杨油层油成藏主要受以下3个因素控制:①青一段源岩生成的油向下“倒灌”运移区控制着油藏形成与分布区域； ②T2源断裂控制着油运聚的部位；③断裂上升盘是油聚集的主要场所。油源区外扶杨油层油成藏主要受以下2个因素控制:① 位于运移路径上或附近的圈闭才能形成油藏；②断裂上升盘有利于油藏形成。综合上述研究可以得到油源区内T2源断裂附近和油源区外运移路径附近的断裂上升盘应为油勘探的有利目标。

Mechanisms of Oil Migration and Accumulation in F,Y Oil Layers of South Songzhan Region, Songliao Basin

The study on the oil reservoir formation and its conditions matching in space revealed that the oil in F,Y oil layers in south Songzhan region, Songliao basin was derived from K1qn1 source rock in Sanzhao depression and two mechanisms of oil migration and accumulation in F,Y oil layers existed. Within the source rock area, oil from the K1qn1 source rock migrated downward into F,Y layers through the passageway of the T2 faults connecting source rock and reservoir and the driving force of overpressured K1qn1 source rock, and then the oil in F,Y layers migrated short distance along the faults and accumulated in the high fault blocks with the buoyancy force. Outside the source rock area, the oil in F,Y layers, Sanzhao depression migrated laterally to south Songzhan along the sandbody connected by faults with the buoyancy force and then accumulated in the upper walls of the faults. Different model of the reservoir formation has different controlling factors. Within the source rock area, there are 3 factors, one is that the area of oil from the K1qn1 source rock migrated downward controlled the oil pool formation and its distribution; the second is that the T2 faults connecting the source rock and reservoir controlled the place of oil accumulation and the third is that the upper walls of the faults are the main area of oil accumulation. Outside the source rock area, there are 2 factors, one is that the traps located in and near the pathways of oil migration can form reservoirs in them; the second is that the upper walls of the faults are favor of oil reservoir formation. From the above comprehensive study, the areas near the T2 faults connecting source and reservoir within the source rock area and the upper side of the fault near the path of oil migration outside the source rock area should be the favorable objects oil exploration.