渤海上第三系油藏成因机制及勘探效益探讨

渤海油区是渤海湾陆相裂谷盆地的一部分。断裂发育、凸凹相间是其主要的构造特征,多"旋回"是其主要的沉积特征,"复式油气藏"发育是其主要的石油地质特征。近年来在渤海上第三系发现了多个大油田,储量约20×108t,据圈闭幅度、断层特性、油藏特征、勘探-开发效益不同,可将凸起上的油藏分为高-中幅度背斜油藏、低幅度背斜油藏,凹陷内油藏分为大断层伴生的背斜油藏、小断层伴生的背斜油藏。文章较深入地分析了这些油藏的成因机制、油层特征及勘探-开发效益,以期对今后的勘探、评价、开发有一点启示。

Reservoir Forming Mechanism and Exploration Effectiveness in the Neogene of Bohai Sea

The Bohai oil province is a part of the Bohai bay nonmarine rift basin. Faults developed and uplifts alternate with depressions are the main structure features of this area. Multi-cycle is one of the major deposit characteristics whereas composite reservoir system is the basic petroleum geologic features. In recent years, many large oil fields have been discovered in the upper Tertiary of Bohai Sea with a total reserves of two billion tons. The reservoirs found in this area can be divided into four types based on the patterns of closure, fault and pay zone: medium to high amplitude anticlines, low amplitude anticlines on the uplifts; anticlines bordered by large or small faults in the sags. The forming mechanism of the reservoirs and their exploration effectiveness has been discussed here. This article could be guidance for the exploration and development activities in the upper Tertiary of Bohai Sea in the future.