平衡剖面方法在伸展、走滑作用叠加、配比关系分析中的应用——以渤海海域辽东湾坳陷为例  

Application of balanced cross-section method in extension, strike-slip superposition and ratio analysis: A case study of Liaodong Bay depression, Bohai Bay Basin

作　　者：李伟[1,2] 郭甜甜[1,2] 吴智平 徐长贵[3] 吴奎 陈兴鹏 幽鹏飞 郭睿鹏 LI Wei;GUO Tiantian;WU Zhiping;XU Changgui;WU Kui;CHEN Xingpeng;YOU Pengfei;GUO Ruipeng(School of Geosciences,China University of Petroleum(East China),Qingdao,Shandong,266580;Key Laboratory of Deep Oil&Gas Geology and Geophysics(China University of Petroleum),Ministry of Education,Qingdao,Shandong,266580;Tianjin Branch,CNOOC Limited,Tianjin,300452)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]深层油气地质与地球物理教育部重点实验室,中国石油大学(华东),山东青岛266580 [3]中海石油(中国)有限公司天津分公司,天津300452

出　　处：《地质论评》2019年第6期1501-1514,共14页Geological Review

基　　金：国家科技重大专项项目(编号:2016ZX05006-007);国家油气重大专项项目(编号:2016ZX05024-002-001)的成果~~

摘　　要：新生代辽东湾坳陷处于伸展和走滑作用的共同控制之下,二者强弱关系的变化导致了复杂的叠加、配比关系,本文利用平衡剖面方法,选取了不同地区垂直和平行于主干断裂的两个方向地质剖面进行了平衡剖面的恢复和伸展率的计算,进而探讨了辽东湾坳陷新生代各演化阶段伸展、走滑作用的叠加配比关系,结果表明:始新统孔店组—渐新统沙河街组四段、三段沉积期,辽东湾坳陷以伸展作用为主,走滑作用相对较弱;沙河街组二段—沙河街组一段沉积期表现为弱伸展、弱走滑;渐新统东营组沉积期转变为强走滑、弱伸展,辽中—辽东地区走滑作用强于辽西地区,而伸展作用辽西强于辽中—辽东地区;新近纪—第四纪,辽东湾坳陷伸展和走滑作用均相对较弱,整体拗陷.不同时期伸展和走滑作用的叠加、配比关系控制了辽东湾坳陷构造格局、构造样式的时空差异.本文所提出的理论和方法适用于中国东部多数伸展和走滑作用共同控制的盆地类型,尤其针对主走滑断裂附近发育相当数量走滑派生次级断裂的情况结果更为准确.Objectives:During the Cenozoic evolution of the Liaodong(eastern Liaoning)Bay Depression,Bohai Bay basin,it was controlled by the interaction of extension and strike-slip stress.These two properties stress changed in different stages,result in the complicated superposition and ratio between extension and strike-slip.This complicated relationship is one of the most important factors for the evolution of the depression,but it is a lack of research.In this paper,we aim to extract the superposition and ratio of extension and strike-slip and restore the Cenozoic evolution of the Liaodong Bay Depression.Methods:Based on fine interpretation of 3D seismic data,this paper restored the tectonic evolution history of the typical section and calculated the cross-section extension rate through balanced cross-section method,which were parallel to or perpendicular to the main fault in Liaoxi sag and Liaozhong sag.Finally,superposition and ratio of extension and strike-slip were analyzed at the different stage in the Liaodong bay depression in Cenozoic.Results:The result shows that Liaodong Bay Depression was dominated by extension,and strike-slip was relatively weak during the sedimentary period from Kongdian Formation to Sha-3 Member.While Liaodong Bay Depression was controlled by weak extension and weak strike-slip during Sha-2 and Sha-1 Member depositional period.Further,Liaodong Bay Depression was dominated by intense strike-slip and weak extension during Dongying Formation depositional period.The strike-slip displacement of Liaozhong and Liaodong area was larger than Liaoxi area,while the extension displacement of Liaoxi area was larger than Liaozhong and Liaodong area at this stage.Weak extension and weak strike-slip controlled development of Liaodong Bay Depression during the Neogene and Quaternary.Conclusions:The superposition and proportion of extensional and strike-slip controlled the temporal and spatial differences of structural deformation in the Liaodong Bay Depression at different development stage.The theory and

关 键 词：伸展、走滑作用 叠加、配比关系 平衡剖面 辽东湾坳陷 新生代 

分 类 号：P61[天文地球—矿床学]