梁家楼—小营地区沙二段三角洲沉积再认识

Recognition on the delta of the second member of Shahejie Formation in Liangjialou-Xiaoying area

长期以来,梁家楼—小营地区沙二段砂泥岩薄互层沉积被认为是形成于沙三段沉积早期的东营三角洲的继承发育。通过对该区古地形、地貌、沉积特征及古物源体系的分析,对沉积体系的时空展布特征及油气成藏规律形成了新的认识:该区沙二段具有多物源体系的特征,发育了三角洲、滨浅湖滩坝及斜坡型近源扇三角洲等多种沉积类型;构造(断裂)、岩性、岩相共同控制了油气藏的形成。正确、客观的地质认识是指导该区沙二段油气勘探的关键,对构造、地层和沉积成藏规律的综合分析为该区今后的油气勘探提供了新的思路。

For a long time,the thin alternate layers of sand-shale in the second member of Shahejie Formation has been thought to be the inheritor of Dongying delta formed in the early third member of Shahejie Formation. According to the analysis of paleo-topography,physiognomy,sedimentary characteristics and source areas,the new idea about the space-time distribution of sedimentary systems and reservoir-forming rule were suggested. It is thought that the second member of Shahejie Formation of Liangjialou and Xiaoying area was composed of multi-source systems with several kinds of sediment types such as delta,fan-delta,beach and bar. Faults,lithology and facies controlled the formatiof Shahejie Formation on and distribution of hydrocarbon reservoirs. Based on the standpoint mentioned above,a new design of the exploration of the secord member of Shahejie Formation was proposed.