【摘要】 利用地震、测井、录井等资料,对辽河盆地东部凹陷北段古近系进行了层序地层学分析,并对每个层序的发育特征、生储盖组合及油气藏类型进行了详细研究。结果表明,该区古近系可划分为SⅠ,SⅡ,SⅢ和SⅣ4个层序,分别对应于房身泡组、沙三段、沙一段沙二段和东营组。SⅡ层序水进体系域最大湖泛期沉积的半深湖深湖相暗色泥岩是研究区的主力烃源岩系;SⅢ层序水进体系域最大湖泛面附近的浅湖相泥岩是最重要的区域盖层。良好的生储盖配置使SⅡ层序、SⅢ层序水进体系域的扇三角洲、滩坝及浊积扇砂体成为本区最佳勘探目标层。SⅡ层序高位体系域生储条件配置好,又有SⅢ层序区域盖层的整体封盖,油气聚集受局部盖层直接控制,可成为较有利的勘探目的层。SⅡ层序、SⅢ层序低位体系域的冲积扇、辫状河砂体体积规模较小,难以形成大油气藏。更多还原

【Abstract】 According to the seismic data, well logging data and logging data, the sequence stratigraphy of the Palaeogene of the northern section in the eastern sag of Liaohe Basin was researched. As a super sequence in this area, the Palaeogene was classified into four sequences. The characteristics of sequence development, source-reservoir-seal assemblage and types of hydrocarbon reservoir for each sequence were discussed in detail. The dark colored shale of deep lacustrine facies in the transgressive system tract (TST) of S_Ⅱ sequence deposited around the maximum flooding surface (MFS) is the main source rock in this area. The shale of shallow lacustrine facies in the TST of S_Ⅲ sequence around the MFS is the most important regional seal rock. The fan delta, sand beach, sand bars and turbidite fan in the TST of S_Ⅱ and S_Ⅲ sequences are the most favorable exploration targets because of favorable source-reservoir-seal assemblages. Since the high-stand system tract (HST) in S_Ⅱ sequence has good source-reservoir assemblage and is covered by the regional seal of S_Ⅲ sequence, the hydrocarbon accumulation in this area is controlled by the local seal rock. The HST of S_Ⅱ sequence becomes the second favorable exploration target zone. Because the scales of the sand bodies of alluvial fan and braided river in low-stand system tract (LST) of S_Ⅱ and S_Ⅲ sequences are limited, the formation of a large hydrocarbon accumulation is difficult.更多还原