敦-密断裂左行走滑三维有限元模拟  

3D finite element simulation on sinistral strike—slip of Dunhua—Mishan fault

作　　者：赵英利[1] 刘永江[1] 韩国卿[1] 温泉波[1] 李伟[1] 梁道俊[1,2] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]金日成综合大学地质系

出　　处：《世界地质》2009年第3期310-317,共8页World Geology

基　　金：国家重点基金项目(40739905);中国石油化工股份有限公司科技开发项目(G0800-06-ZS-327);博士点基金项目(200801830041)联合资助

摘　　要：敦-密-断布列亚裂带是郯庐断裂北段的重要分支之一,具有左行走滑剪切性质,其走滑位移量的大小一直存在很大争议。应用ANSYS三维有限元模拟软件,对研究区地质体建立理想模型,并采用分段施力和连续施力两种方法进行构造几何学错移的数值模拟,探讨敦--密断裂带的走滑位移量。模拟结果表明:采用分段施力方式得到的累计走滑位移量为273.8 km,连续施力方式得到的位移量为406.8 km,说明在不考虑外界阻力影响及地质体内部形变吸收的位移量时,郯庐断裂由南到北具有整体统一的走滑位移量。综合考虑布列亚—佳木斯地块的阻挡及地质体内部的韧性变形和逆冲推覆构造对走滑位移量的吸收等地质因素,认为敦--密断裂带实际位移量应比模拟数值小,也证实了郯庐断裂走滑位移量可能存在由南至北逐渐递减的规律。Dunhua-Mishan fault zone with sinistral strike-slip shear property is one of the important branches of northern Tancheng-Lujiang fault zone, and there have long been controversies about its strike-slip displacement. An ideal model of the geological bodies has been established, and the strike-slip displacement of the Dunhua-Mishan fault zone was simulated by discontinuous and continuous force application methods using 3D finite element simulation program-ANSYS. The results show accumulate displacement by discontinuous force is 273.8 km and by continuous force is 406.8 km, which indicate that Tancheng-Lujiang fault zone has consistent displacement from south to north if ignoring the external resistance influence and the deformation and absorption displacement by inner geological bodies. The authors consider the actual displacement of Dunhua-Mishan fault zone should be less than the simulated result by ideal model under the comprehensive consideration of the resistance by Bureya-Jiamusi block and the absorption to displacement by ductile deformation and thrust nappe structure in inner geological bodies, which provides a significant evidence of Tancheng-Lujiang fault zone has decreasing displacement from south to north.

关 键 词：敦-密断裂 郯庐断裂 左行走滑 三维有限元模拟 ANSYS软件 

分 类 号：P542.3[天文地球—构造地质学]