利用GAMIT10.4和BERNESE5.2软件,分别对川滇地区中国地壳运动观测网络51个GNSS基准站2010—2014年的观测数据进行处理.两者解算所得单日解基线和坐标时间序列离散度优于10mm,且变化趋势一致,吻合度较高.基线重复率水平向优于1+4×10-9L;垂向优于4+6×10-9L(单位mm,其中L表示基线长度,单位m).利用PL+VW噪声模型进行了速度估计,获取了川滇地区相对欧亚板块地壳运动速度场.结果显示:除滇西南地区呈现出由西向东的增大趋势外,川滇块体其它区域地壳运动特征由北往南、由西往东呈逐渐衰减趋势;运动方向持续围绕喜马拉雅东结点作顺时针旋转,且仍然存在着南北向强烈的挤压特征.以安宁河-则木河断裂、小江断裂和红河断裂为界,选用了两侧能反映震间断裂构造特征的GPS测站,分析了断裂两侧的速度差异.并利用平行断层的速度剖面,拟合反正切函数变化趋势,获取了断裂带可能的变形宽度.%Based on GAMIT and BERNESE softwares ,the GPS data of 51 base stations from 2010 -2014 from Crustal Movement Observation Network of China is processed and analysed .The discrete degree of both baseline and coordinate time series are better than 10 mm .The change tendency is consistent and the coincidence degree is high .The baseline repeatability is better than 1+4 × 10-9 L in horizontal direction and 4+6 × 10-9 L in vertical direction .Crustal movement velocity field of Sichuan-Yunnan region relative to Eurasia plate is obtained .The results show that except the southwest of Yunnan which velocity increases from west to east ,the crustal movement characteristics of other Sichuan-Yunnan region gradually reduces from north to south ,and from west to east .Still ,movement direction shows clockwise rotation around the Himalayan east nodes ,and strong extrusion characteristics from north and south .Considering Anning River-Zemu River fault and Xiaojiang fault and Honghe fault as the boundary respectively ,the GPS station reflecting fault characteristics on both sides are chozen .The velocity difference on both sides of fault is analyzed .By the velocity profile paralleling with the fault ,the arctangent function trend is fitted and the deformation width of the fault zone is obtained .
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