东营三角洲演化特征与岩性圈闭分布规律

摘要

东营三角洲是东营凹陷古近系沙河街组沙三段的主要沉积体系之一,为一大型复合三角洲.该三角洲形成的浊积砂体岩性圈闭是东营凹陷沙三段重要的勘探目标,近几年平均每年发现的岩性油藏石油储量超过千万吨.为了给东营三角洲隐蔽油气藏进一步的勘探提供科学依据,运用高分辨率层序地层学理论和分析方法,在建立高频层序地层格架的基础上,研究东营三角洲演化过程、古构造坡折发育类型及不同期次三角洲与构造坡折的配置关系,分析这些因素对岩性圈闭形成的重要作用,认为在进积时期推进距离较远(三角洲进积作用大于加积作用)、退积时期湖泛规模较大条件下发育的三角洲朵叶体易形成具有一定规模的浊积扇.%Turbidity lithologic trap developed in the Dongying Delta is one of important exploration targets in Sha Member 3of the Shahejie Formation in Shengli Oilfield. Over 10 million tons of oil reserves had been discovered from the lithologictrap annually in last few years. In-depth understanding of its formation mechanism and distribution is crucial for improvingexploration success in such subtle lithologic reservoirs. Applying the theory and methodology of high resolution sequencestratigraphy, the genetic types and distribution of turbidity sandbody related to the Dongying Delta are discussed dependingto the construction of stratigraphic framework, and delta evolution process, classification of paleo-tectonic break type andmatching of different stage delta with tectonic break are analyzed.