库车坳陷大北地区巴什基奇克组隐性断层特征与发育模式  

Characteristics and development model of subtle faults in Bashijiqike Formation,Dabei area,Kuqa Depression

作　　者：金江宁[1] 易泽军 李青[1] 王海学[2] 屈元基 姜涵博 李志豪[1] 何韫多 Jin Jiangning;Yi Zejun;Li Qing;Wang Haixue;Qu Yuanji;Jiang Hanbo;Li Zhihao;He Yunduo(Exploration and Development Research Institute,China Petroleum Tarim Oilfield Company,Korla,Xinjiang 841000;School of Earth Sciences,Northeast Petroleum University,Daqing,Heilongjiang 163318)

机构地区：[1]中国石油塔里木油田公司勘探开发研究院,新疆库尔勒841000 [2]东北石油大学地球科学学院,黑龙江大庆163318

出　　处：《地质科学》2024年第3期760-767,共8页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：黑龙江省自然科学基金优秀青年项目(编号:YQ2022D007)资助。

摘　　要：库车坳陷作为塔里木盆地新生代再生前陆盆地,盐下叠瓦状构造楔发育,多个断片在巴什基奇克组发现了天然气藏。随着气藏的不断开发,多个气藏发生不同程度水侵,前人研究表明,隐性断层作为沟通底水或边水的高渗透通道,是导致水侵的主要原因,能否有效识别隐性断层直接影响气藏开发效果。然而,由于膏盐岩层的影响,盐下构造的地震分辨率较低,使用地震属性方法识别隐性断层难度较大。本次以大北地区为例,采用地质与地球物理相结合的思路,在钻井与地震属性方法识别的3条隐性断层基础上,通过断距—距离曲线分析主干逆冲断裂的分段性,并结合应力分析,建立了两种隐性断层发育模式。结果表明隐性断层的形成受局部应力场和区域应力场的共同控制。主干逆冲断层构造转换带是隐性断层优势发育位置,随着断层发生分段生长连接,构造转换带将由挤压应力状态逐渐变为走滑应力状态,形成的隐性断层走向也将发生变化。区域应力的走滑分量则是控制北东向隐性断层远离主干边界断层后走向,维持稳定的另一重要因素。本次研究成果将为库车坳陷隐性断层的识别和预测提供重要的地质约束。As a Tarim Basin Cenozoic regenerated foreland basin,the Kuqa Depression is characterized by the development of imbricate structural wedges under salt.With the continuous development of gas reservoirs,many gas reservoirs have water invasion in different degrees.Previous studies have shown that the subtle fault,as a high permeability channel to communicate bottom water or edge water,is the main cause of water invasion,the effective identification of subtle faults directly affects the development effect of gas reservoirs.However,due to the influence of gypsum-salt strata,the seismic resolution of subsalt structures is low,and it is difficult to identify the subtle faults by using seismic attribute method.Taking the Dabei X structure as an example,this paper adopts the idea of combining geology with geophysics,and based on the 3 subtle faults identified by drilling and seismic attribute methods,based on the fault distance-distance curve and stress analysis,two types of subtle fault development models are established.The results show that the formation of the subtle fault is controlled by both local stress field and regional stress field.The main thrust fault structural transition zone is the dominant developing position of the subtle fault.With the fault growing and connecting in segments,the structural transition zone will gradually change from the state of extrusion stress to that of strike slip stress,the strike of the subtle fault will also change.The strike-slip component of the regional stress is another important factor to control the strike of the NE-trending subtle fault when it is far away from the main boundary fault.The results of this study will provide important geological constraints for the identification and prediction of subtle faults in the greater North Bozi area of the Kuqa Depression.

关 键 词：库车坳陷 逆冲断裂 隐性断层 断距—距离曲线 发育模式 

分 类 号：P542[天文地球—构造地质学]