【摘要】 汶川8.0级特大地震是岷江上游流域最新一次区域构造活动,在此次地震中,岷江河道因北川-映秀断裂北西盘的右旋走滑作用而被水平错动0.8±0.2 m,岷江河道南西方向的河流阶地也被同步位错0.6±0.1 m。切过龙门山主干断裂的岷江上游干、支流水系因若干次历史地震驱动的走滑作用而发生同步弯曲。根据水系水平扭错量和岷江干、支流初始形成时间计算可知,穿越岷江支流河道的汶川-茂县断裂右旋走滑速率为1～1.4 mm/a,切过岷江干流河道的北川-映秀断裂和彭县-灌县断裂右旋滑动速率分别为0.94 mm/a和0.71 mm/a。计算结果表明,龙门山各主干断裂右旋走滑作用有自北西向南东减弱的趋势。更多还原

【Abstract】 The Wenchuan Ms8.0 earthquake was the latest regional tectonic activity in the upper Min River basin.The horizontal displacement of Min River channel reached 0.8±0.2 m for dextral strike slip movement of Beichuan-Yingxiu fault,and the synchronous displacement of the river terrace in the southwest side of Min River channel reaches 0.6±0.1 m.The horizontal movement of the main and tributary of Min River were caused by the strike slipping in historical earthquakes.The dextral strike-slip rate of faults was calculated according to the horizontal slip amount and initial formation time of water system.The strike-slip rate of Wenchan-Maoxian fault is 1-1.4 mm/a,the strike-slip rate of Beichuan-Yingxiu fault is 0.94mm/a,the strike-slip rate of Pengxian-Guanxian fault is 0.71 mm/a.The intensity of dextral strike slipping of main faults in the Longmen Mountain were decreased from northwest to southeast.更多还原