【摘要】 综合岩心、钻井、地震等资料,运用层序地层学、现代沉积学的思路和方法,对黄骅坳陷中区古近系东营组的沉积体系特征进行了分析,指出东营组沉积时期处于盆地断—拗转化阶段,主要发育湖泊三角洲和湖泊体系,局部地区发育扇三角洲和浊积体系等。沉积体系的时空分布和演化特征受控于构造背景和层序结构样式的差异,表现为东三段层序(SQEd3)以低位域三角洲和范围扩大的高位域三角洲为主;东二段层序(SQEd2)、东一下段层序(SQEd1x)以板桥次凹等局部地区发育的低位域三角洲和普遍发育的高位域三角洲为主;东一上段层序(SQEd1s)低位域三角洲和高位域三角洲主要分布于歧南次凹和歧北次凹,总体形成了缓坡背景、断控斜坡背景和多级断阶背景下的3类沉积模式。基于上述研究,认为研究区发育5类有利圈闭区:坡折带附近的隐蔽圈闭区、越过凹陷中心的上超尖灭圈闭区、构造—岩性复合圈闭区、低位域和高位域浊积砂体形成的岩性圈闭区、下切谷充填岩性圈闭区,构成了6个有利的勘探区带,这对于指导研究区东营组的油气勘探具有重要意义。更多还原

【Abstract】 The characteristics of depositional systems of the Dongying Formation in the central area of the Huanghua Depression were analyzed based on analyses of sequence stratigraphy and modern sedimentology combined with core,well and seismic data. The Dongying Formation was formed in the transitional period of tectonic evolution from rifting to sagging stages. Mainly lacustrine deltaic and lacustrine systems were developed. Fan delta and turbidite systems were only distributed sporadically. Time-spatial distribution and evolution of the depositional systems were controlled by tectonic setting and sequence configuration. Three typical depositional models were established and they include gentle slope,fault-controlled steep slope,and multi-level step-fault. In details,lowstand and highstand systems tracts deltas were mainly developed in the SQEd3. Lowstand systems tract delta in local areas such as Banqiao Subsag and highstand systems tract delta with a large range were mainly developed in the SQEd2 and SQEd1x. Lowstand and highstand systems tract deltas were developed in the Qinan and Qibei Subsags in the SQEd1s. Based on the analysis of depositional systems,five types of traps were identified. They are subtle traps near the slope break,onlap pinchout traps across the sag center,structural-lithologic traps,and subtle traps including lowstand systems tract turbidites,highstand systems tract turbidites and incised valley. Six favorable exploration areas were predicted according to the characteristics of traps.更多还原