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东海陆架盆地西湖凹陷自新生代以来经历了陆内拉张断陷、转换边缘坳陷、陆内迁移坳陷和陆架边缘坳陷等4种原型演化,对油气的生成、运聚起到了重要的控制作用。从地质作用与油气响应的关系出发,以平湖组为例探讨了西湖凹陷新生代构造演化对油气的控制作用。受构造演化影响,平湖组不同时期的厚度(或残留厚度)在凹陷不同部位有所不同,导致主力烃源岩生烃条件多期变化。同时,构造演化控制了西湖凹陷温度场在时间和空间上的变化,提供了烃源岩成熟或资源结构变化的地温条件。另外,构造演化造成油气运移方向的变化,龙井运动以前,油气主要向西部斜坡带和东部隆起带运移;而在龙井运动以后,除上述方向外,油气还在中央背斜带发生短距离的侧向运移和垂向运移。
Since the Cenozoic of the East China Sea Shelf Basin, the Xihu Sag experienced four prototype evolutions such as intracontinental Zhangla fault, transitional margin depression, intracontinental migration depression and shelf margin depression, which has played an important role in the formation and migration of oil and gas Control effect. Based on the relationship between geological functions and oil-gas response, taking Pinghu Formation as an example, the paper discusses the controlling effect of Cenozoic tectonic evolution on hydrocarbon in Xihu Sag. Affected by the tectonic evolution, the thickness (or residual thickness) of the Pinghu Formation in different periods of the depression is different in different parts of the sag, causing the hydrocarbon generation conditions of the main source rocks to change periodically. At the same time, the tectonic evolution controlled the temporal and spatial variations of the temperature field in the Xihu Sag, and provided the geothermal conditions for the source rocks to mature or change the resource structure. In addition, tectonic evolution led to changes in the direction of hydrocarbon migration. Before Longjing movement, oil and gas mainly migrated to the western slope belt and the eastern uplift belt. After the Longjing movement, in addition to the above directions, oil and gas also occurred in the central anticline belt over a short distance Lateral migration and vertical migration.