新丰江地震S波偏振的初步研究

Preliminary study on polarization of S-wave of Xinfengjiang earthquakes

根据新丰江地震台记录的 2 0 0 1年 2月 6日新丰江小震群数字化资料 ,分析计算了该震群的S波分裂的偏振参数。在与新丰江地区的最大主应力方向和构造、介质特性对比后 ,认为本文所得的S波偏振方向 (NW6 0°)与该区实际的活动断裂分布和主压应力轴方向 (NW6 0°)基本相同。作为该区地壳微裂隙的NW优势取向 ,是应力场作用下裂隙定向排列的结果。因此 。

With the data recorded by Guangdong Digital Seismograph Network on Feb.21,2001, we calculated the polarization parameters of S-wave splitting. After comparing with the direction of maximum principle stress and the feature of tectonic settings and medium in Xinfengjiang area, we thought the polarization direction (NW60°) of S-wave splitting is identical with the direction of maximum principal stress. The dominant direction NW of crustal crack is the result of the crack directional range in the stress field. So, polarization direction of S-wave splitting may be an effective parameter for studying the feature of medium anisotropy and regional stress field.