【摘要】 利用1999—2001、2001—2004和2004—2007三个时段的GPS速度场数据,基于块体运动的线性模型(RELSM)研究了小江断裂带的运动与变形的时空特征,得出小江断裂的总体左旋走滑速率为3.0～7.1 mm/a。根据断裂带历史地震地表破裂分段,结合GPS速度剖面,研究了断裂带的分段应变积累时空特征,结果表明:1)小江断裂各个分段不同时间段的相对运动与变形方式有较好一致性,均呈现左旋走滑兼拉张的运动特征;2)RELSM得出小江断裂分段滑动的差异性,表现为沿断裂带的北段到南段的左旋滑动速率逐渐减小;3)小江断裂各段应变积累特征表明,北段高于中北段,中南段及南段不利于积累或积累水平低;4)小江断裂带北段为相对闭锁且剪切应变积累速度较高的异常区域。更多还原

【Abstract】 Using the GPS velocity field data from 1999-2001,2001-2004 and 2004-2007 on short time scales,we studied the overall motion characteristics of Xiaojiang fault through linear model of block(RELSM),and reached the result that its average left-lateral slip rate is about 3.0~7.1 mm/a.According to the segmentation of surface rupture of fault due to historical earthquakes,we analyze the different characteristics of space-time of strain accumulation on every fragment by using the method of GPS velocity profile.The results indicated as follows.1)The sections in different time periods of Xiaojiang fault have better consistency on relative motion and deformation mode,are sinistral strike-slip and pull-apart movement characteristics.2)RELSM results show segment difference and decrease of slip rate from north to south.3)Strain accumulation features show,the northern section above middle north section,middle south section and the southern section are not conducive to the accumulation or low levels of it.4)The northern section of Xiaojiang fault zone is abnormal regions which was relatively closed and there was high rate of shear strain accumulation.更多还原