北塘凹陷古近系沙河街组三段沉积特征及储层的影响因素

Sedimentation characteristics and factors affecting the reservoir in Palaeogene Shasan Member of Beitang sag, Huanghua depression

北塘凹陷古近系沙河街组三段储层储集物性差是造成其油藏产量偏低的主要原因。在观察岩心、分析沉积相和沉积体系平面分布的基础上,利用大量岩心物性数据和其他地质资料,系统讨论了其储层特征及影响储层储集性能的主要地质因素。认为北塘凹陷古近系沙河街组三段主要发育扇三角洲、滑塌重力流、湖相等类型沉积相,发育北部和西部两个物源,主要含油气区塘沽、新村等地区位于两个物源的交汇区,以发育中等差储层为主,影响储层发育的主要因素包括原始的沉积相带、成岩作用(压实作用、胶结作用和溶解作用等)、油气成藏时间、油藏异常压力以及火成岩分布等。

The low reservoir productivity of Paleogene Shasan Member in Beitang sag is mainly attributed to its bad reservoir character. Based on large quantities of core and other geological data, the authors systematically discussed sedimentation, main reservoir characteristics of Shasan Member and the affecting factors. Sedimentary facies of Shasan Member in the study area are mainly fan delta deposition, gravity-slide deposition and lake deposition. The reservoirs belong to medium to bad reservoirs in size. Sedimentary facies, diagenetic actions such as compaction, cementation and dissolution, oil pool formation time, reservoir pressure and distribution of igneous rocks are major factors affecting the reservoir quality.