摘要
基于2014年以来云南地区GNSS连续观测资料,采用最小二乘配置、克里金插值等方法进行速度场、应变参数的求解,分析云南地区近期地壳活动特性及其强震影响。结果表明,以文山测点为基准的速度场存在整体的顺时针运动特性,且各测点运动方向存在差异;云南整体区域最大剪应变积累存在北强南弱、西强东弱的特性,目前滇西北地区最大剪应变增强最快,滇南至滇西南等区域挤压应变积累明显。2014年内的3次6级以上强震在宏观上与最大剪应变的空间分布保持了较好的一致性,且地震的发生并没有改变云南整体区域应力、应变分布格局和增长趋势。
Based on continuous observation data of GNSS in Yunnan since 2014,the velocity and strain parameters are solved by least squares configuration and the Kriging interpolation method.The velocity field and strain field results are used to analyze recent crust activity features of Yunnan region,as well as the resulting influences on strong earthquakes.The results show that the velocity field,based on Wenshan measurement point,show a whole clockwise motion characteristic,and the direction of motion is different.The maximum shear strain accumulation in the whole area of Yunnan is fastest and strongest in northwestern Yunnan,and the squeezing strain accumulates in south and southwestern Yunnan.In the year 2014,the strong earthquakes of magnitude 6 and above have maintained a good consistency with the maximum shear strain in the macroscopic direction,and the occurrence of the earthquake does not change the stress and strain distribution pattern and growth trend of the whole area in Yunnan.
引文
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