裂陷盆地洼槽演化规律研究——以歧口凹陷西部为例  

Sag evolution in muti-phase rifts: Case study on the Paleogene of Qikou Depression

作　　者：刘世瑞 付晓飞[1,2] 王有功[1,2] 刘海涛[3] 姜文亚[4] 李永新[3] Liu Shirui;Fu Xiaofei;Wang Yougong;Liu Haitao;Jiang Wenya;Li Yongxin(Earth Science Department of Northeast Petroleum University,Daqing,Heilongjiang 163318;CNPC Fault Controlling Reserviors Laboratory,Northeast Petroleum University,Daqing,Heilongjiang163318;Research Institute of Petroleum Exploration and Development,Beijing100083;Petroleum Exploration and Development Research Institute of Petro China Dagang Oilfield Company,Tianjin300280)

机构地区：[1]东北石油大学地球科学学院,黑龙江大庆163318 [2]东北石油大学CNPC断裂控藏研究室,黑龙江大庆163318 [3]中国石油勘探开发研究院,北京100083 [4]中国石油大港油田勘探开发研究院,天津300280

出　　处：《地质科学》2020年第1期81-92,共12页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金项目“深层油气藏盖层封闭能力动态演化过程及完整性定量评价”(编号:U1562214)和中国石油股份公司重大科技项目“走滑断裂带油气地质研究与勘探潜力评价”(编号:2019D-0706)资助。

摘　　要：裂陷盆地中洼槽的演化规律对疑灶的分布及生绘能力具有明显控制作用。歧口凹陷在古近纪经历了两期两向的裂陷活动,洼槽结构较为复杂,裂陷I幕,在N W-SE向伸展作用下,形成了多个NE-NNE向洼槽;至裂陷U幕,受N・S向伸展作用,NE-NNE向断层活动性逐渐减弱,NE-NNE向洼槽开始萎缩。本文基于控洼断层的空间组合样式及传播方式、洼槽内层序界面的接触关系,建立洼槽演化的3种模式;结合典型地震剖面、地层厚度图、控洼断层断距一距离曲线等相关证据,识别出歧口凹陷洼槽的演化规律。其中,歧南洼槽属于“生长连接型洼槽演化模式”,板桥洼槽属于“固定长度型洼槽演化模式”,而歧北洼槽属于“侧列叠覆型洼槽演化模式”。In multi-phase rift basin, the evolution of sag plays a significant role in controlling the distribution and hydrocarbon generation ability of source kitchens. Qikou Depression experienced two periods of rifting in the Paleogene, so sag structure is very complex. In rift Ⅰ phase, under the NW-SE extension, several NE?NNE sags were formed. In rift Ⅱ phase, the activity of NE-NNE fault was gradually weakened by the N-S extension, while the E-W orientation fault played a main role in the depression. In this paper, we established three models of the sag evolution, based on the spatial combination style and propagation mechanism of main fault, interpretation of seismic reflection terminations, then we used typical seismic profiles, formation thickness maps, throw-distance curves and other relevant evidence to identify the evolution of Qikou Depression. Results indicate that Qinan Sag belongs to the “sag evolution controlled by isolated fault model”, Banqiao Sag belongs to the “sag evolution controlled by coherent fault model”, and Qibei Sag belongs to the “sag evolution controlled by overlay fault model”.

关 键 词：断层分段生K 洼槽结构 洼槽演化 歧口凹陷 裂陷盆地 

分 类 号：P542[天文地球—构造地质学] TE121[天文地球—地质学]