论文详情
该文以西湖凹陷三潭深凹南部近年来油气勘探不够理想的G构造为研究目标，从石油地质基本条件角度分析了平湖组、花港组不同的生烃条件、运移条件、岩相组合以及断裂系统特征，同时对火成岩测龄、镜煤反射率、包裹体均一温度、有机地化等多种化验资料的综合分析后认为G构造平湖组在龙井运动前具有自生自储、封存箱成藏的有利条件，龙井运动后深部油气垂向运移至平上段，具有侧向砂体疏导、岩性成藏的可能。而花港组处于流体势不利位置，是花港组构造圈闭成藏困难的主要原因。结合分析G构造的成藏演化过程，认为下步可以关注中央背斜带西翼下降盘具有断裂侧向封堵的构造位置或中央背斜带主构造周边的低缓背斜。
In this paper, the G structure, which is not ideal in oil and gas exploration in the southern part of Santan Depression in Xihu Sag, is regarded as the research target, the differences in hydrocarbon generation conditions, migration conditions, lithofacies association and fault system characteristics between Pinghu Formation and Huagang Formation are analyzed from the perspective of basic petroleum geological conditions. Based on the comprehensive analysis of igneous rock age, vitrinite reflectance, inclusion homogenization temperature, organic geochemistry and other laboratory data, it is concluded that Pinghu Formation of G structure had the favorable conditions of self-generation , self-storage and compartment reservoir forming before Longjing movement. After Longjing movement, deep oil and gas migrated vertically to the upper member of Pinghu Formation, which has the possibility of lateral sand body dredging and formation of lithologic reservoir. The unfavorable position of fluid potential in Huagang Formation is the main reason for the difficulty of hydrocarbon accumulation in structural traps of Huagang Formation. Combined with the analysis of the accumulation and evolution process of G structure, it is suggested that the next step can be to focus on the structure of the downthrown block of the western wing of the central anticlinal zone with fault lateral seal or the low gentle anticline around the main structure of the central anticlinal zone.