共轭走滑断裂形成演化的控制因素及物理模拟实验  

Controlling Factors and Physical Simulation Experiments on Formation and Evolution of Conjugate Strike-Slip Faults

作　　者：代兰 邬光辉 陈鑫 朱永峰[2] 陈思锜 罗鑫 胡明[1] DAI Lan;WU Guanghui;CHEN Xin;ZHU Yongfeng;CHEN Siqi;LUO Xin;HU Ming(School of Earth Science and Technology,Southwest Petroleum University,Chengdu,Sichuan 610500,China;Tarim Oilfield Company,PetroChina,Korla,Xinjiang 841000,China;Chongqing Gas Mine,Southwest Oil&Gas Field Company,PetroChina,Chongqing 40000,China)

机构地区：[1]西南石油大学地球科学与技术学院,成都610500 [2]中国石油塔里木油田分公司,新疆库尔勒841000 [3]中国石油西南油气田分公司重庆气矿,重庆400000

出　　处：《新疆石油地质》2023年第1期43-50,共8页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(41972121);中国石油—西南石油大学创新联合体项目(2020CX010101)。

摘　　要：针对“X”型共轭走滑断裂复杂的成因,结合塔里木盆地塔北地区大型“X”型共轭走滑断裂的地质情况,设计7组不同参数的“X”型共轭走滑断裂砂箱实验,探究其形成的控制因素与演化过程。实验结果表明,厚度大、宽度大及黏土矿物含量多的模型,在双侧快速挤压作用下,容易形成共轭走滑断裂;断裂尾段扩张与一组方向断裂优势发育特征显著,而断裂连接生长与叠覆区局化作用弱。形成共轭走滑断裂需要3方面的条件:具一定厚度的盖层,缺少先期或先存断裂;岩石物理均一性好,有一定的黏塑性,运动速率较高;双向挤压。自然界与实验中均难以形成对称的纯剪共轭走滑断裂,大多为转向一组优势方向发育的单剪走滑断裂;塔里木盆地共轭走滑断裂也存在不对称性,发育以北西—南东向为优势的单剪断裂,小位移继承性是大型共轭走滑断裂系统发育的主控因素。The origins of X-shaped conjugate strike-slip faults are complex. Considering the geological conditions of large X-shaped conjugate strike-slip faults in the Tabei area of the Tarim basin,7 sets of sandbox experiments with different parameters were designed to explore the controlling factors and evolution process of the X-shaped conjugate strike-slip faults. The experimental results show that conjugate strike-slip faults tends to be formed in the model with large thickness,large width and high clay content under the rapid compression on both sides. In the experiment,the fault tail propagation and the dominant development of a group of faults are obvious,while the fault linkage growth and the localization of overlapping area are weak. The formation of conjugate strike-slip faults requires three conditions: certain caprock thickness,and lack of pre-existing faults;good physical homogeneity of rocks,certain viscoplasticity,and high movement rate;and twoway compression. In the natural world and experiments,symmetrical pure shear conjugate strike-slip faults can hardly be formed,but most faults are single-shear strike-slip faults that develop as a group in dominant direction. In the Tarim basin,the conjugate strike-slip faults are also asymmetric,and they are dominantly single-shear faults in NW-SE direction;the inherited development with small displacements is the main controlling factor for the formation of large-scale conjugate strike-slip faults.

关 键 词：塔里木盆地 共轭走滑断裂 构造物理模拟 控制因素 成因机制 演化模式 

分 类 号：TE122.1[石油与天然气工程—油气勘探]