东营凹陷古近系沙河街组富有机质页岩层系震积岩发育特征及地质意义  

Development characteristics and geological significance of seismites in organic-rich shale strata in Paleogene Shahejie Formation,Dongying Depression

作　　者：侯中帅 陈世悦[3] 杨怀宇[4] 张顺[4] 梁钊 Hou Zhongshuai;Chen Shiyue;Yang Huaiyu;Zhang Shun;Liang Zhao(Hebei Key Laboratory of Strategic Critical Mineral Resources,Hebei GEO University,Shijiazhuang 050031;Energy Research Institute,Hebei GEO University,Shijiazhuang 050031;School of Geosciences,China University of Petroleum(East China),Qingdao,Shandong 266580;Research Institute of Petroleum Exploration and Development,Shengli Oilfield,SINOPEC,Dongying,Shandong 257015)

机构地区：[1]河北省战略性关键矿产资源重点实验室,河北地质大学,石家庄050031 [2]河北地质大学能源研究所,石家庄050031 [3]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [4]中国石化胜利油田分公司勘探开发研究院,山东东营257015

出　　处：《地质科学》2025年第1期90-106,共17页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金项目(编号:41372107);河北地质大学博士科研启动基金项目(编号:BQ2024001);河北省高等学校科学技术研究项目(编号:QN2022060)资助。

摘　　要：东营凹陷古近系沙河街组四段上亚段—沙河街组三段下亚段富有机质页岩中,发育大量与古地震活动有关的震积岩,围绕其开展研究不仅可以深入认识震积岩和富有机质页岩,而且对页岩油气勘探具有积极作用。通过岩心和薄片观察,识别出的震积岩包括软沉积物变形层和震浊积岩。研究区软沉积物变形构造的类型包括小褶皱、液化砂岩脉、负载构造、球枕构造、串珠状构造、布丁构造、小断层和自碎角砾岩。震浊积岩为深湖沉积物滑塌形成的厚度小于2cm的浊积层。古地震活动导致沉积物发生液化和脆性变形,造成沉积物的流动、失稳、压实和破裂,最终形成软沉积物变形和震浊积岩。受震中距、古地形坡度和陆源碎屑输入强度的影响,湖盆中心富有机质页岩层系中震积岩的发育规模较湖盆边缘砂泥岩互层层系明显减小。震积岩的发育对于油气的初次运移和二次运移均具有重要意义,同时其也可以作为潜在的页岩油气储层。A large number of seismites related to paleoearthquakes have developed in the organic-rich shale of the upper submember of member 4 of the Paleogene Shahejie Formation and the lower submember of member 3 of the Paleogene Shahejie Formation in the Dongying Depression.The research on seismites can not only deepen the understanding of seismites and organic-rich shale,but also have a positive effect on shale oil and gas exploration.Based on core and thin section data,seismites consisting of soft sediment deformation layers and seismoturbidites can be observed.The types of soft sediment deformation structures in the study area include small fold,liquefied sandstone vein,load structure,ball-pillow structure,pinch-and-swell structure,boudinage,small fault and autoclastic breccia.Seismoturbidites are turbidite layers less than 2 cm thick formed by the collapse of deep lake sediments.The paleoearthquakes lead to the liquefaction and brittle deformation of the sediments,resulting in the flow,instability,compaction and rupture of the sediments,and eventually form the soft sediment deformation structures and seismoturbidites.Influenced by the distance from the epicenter,palaeotopographic slope and the intensity of terrigenous clastic input,the development scale of seismites in the organic-rich shale series in the center of the lake is significantly smaller than that in the sand-mudstone interlayer series on the edge of the lake.The development of seismites is important for the primary and secondary migration of oil and gas,and can be potential reservoir of shale oil and gas.

关 键 词：震积岩 软沉积物变形构造 震浊积岩 古地震 富有机质页岩 东营凹陷 

分 类 号：P588.2[天文地球—岩石学]