基于多尺度球面小波分析云南地区应变特征

使用GAMIT/GLOBK软件处理2011~2016年云南地区GPS区域站观测数据，扣除同震影响、区域欧拉均匀旋转矢量后，得到该区域的GPS水平速度场，并采用多尺度球面小波模型获取分解尺度分别为6、7、8和9时的云南地区GPS应变场，然后结合云南地区历史MS5.0以上地震信息，以及小江、红河等区域断裂活动情况分析该区域应变场的空间分布特征。结果显示，在区域应变场整体解算中，利用球面小波方法能够适应测站点的疏密变化，多尺度估计地表应变场。主应变、面膨胀和剪应变等分析结果与区域历史地震信息及对应区域断裂活动性质具有较好的吻合性。从应变结果看，红河断裂可能是具有重要构造意义的活动断裂，应变特征显示云南区域被红河断裂划分为2个特征区域；云南地区的鲁甸、腾冲、普洱、大理区域可能是地震活动较为剧烈的区域；小江断裂带中的嵩明区域在不同应变特征中均表现出高度异常，后期应予重点关注。

Analysis the Strain Characteristics of Yunnan:Based on Multi-Scale Spherical Wavelet

Based on the observational data of GPS regional stations in Yunnan area from 2011 to 2016, this paper uses GAMIT/GLOBK software to process observed data, utilizing a high-precise data processing strategy. After deducing the coseismic effect and region Euler uniform rotation vector with the GPS horizontal velocity field relative to the Eurasian plate, we get the regional GPS horizontal velocity field and use it as input data. Finally, using the multi-scale spherical wavelet model that can be decomposed and selected according to the density of GPS stations, we obtain the GPS strain field in Yunnan province at resolution scales 6, 7, 8 and 9. Based on historical MS5 earthquakes in Yunnan province, and the faults such as Xiaojiang and Honghe faults, we analyze the spatial distribution characteristics of the strain field. The results show that, in the integrated solution processing of regional strain field, the spherical wavelet method can adapt to the density change of the stations, and estimate surface strain field with multi-scale. Using multi-scale spherical wavelet to get integral solution strain field is an effective method, showing robust results. The results are in good agreement with historical earthquakes and regional fracture properties. The analysis results of principal strain, dilatation and shear strain are coincidence, regular, and in good agreement with regional historical seismic information and the active faults in the areas. From the result of principal strain rate, dilatation and maximum shear rate in the Yunnan area, which is shown by the spherical wavelet analysis: a) the Honghe fault may be a tectonic fault with important tectonic significance. Strain characteristics indicate that the Yunnan area is divided into two characteristic areas by the Honghe fault; b) the Ludian, Tengchong, Puer, Dali areas may present more intense seismic activity; c) the Songming area in Xiaojiang fault zone shows a high anomaly in multi-scale strain characteristics, and the seismic monitoring activities of this area in the later stage should be a focus for further research.