论文部分内容阅读
采用与永登地震相同的方法,研究了1996年6月1日天祝-古浪5.4级地震前后地壳介质剪切波分裂、电性各向异性随时间的变化特征.结果表明临震前电性主轴、快S偏振方向都是从北偏西方向转为北偏东,而该次地震的P轴为北偏东50°,三者总体上是一致的.由于该次地震与松山电磁台同处一个断层构造上,因此视电阻率变化在各频段均较强,但ρyx比ρxy变化大,这一点与永登地震不同.另外,由于收集的小震资料较少,快慢S波时间延迟的分析结果没能反映出应力强度的积累,另一个原因可能是该次地震孕育与永登地震后应力调整纠缠在一起的结果(两者距离120多公里).
Using the same method as that of the Yongdeng earthquake, the shear-wave splitting and the electric anisotropy of the crust in the medium before and after the Tianzhu-Gulang M 5.4 M-Ms on June 1, 1996 are studied. The results show that the pre- The major axis and the fast S-polarization direction all turn from Northwest to North-East, while the P-axis of this earthquaking is 50 ° E in the east and the whole three are consistent.As a result of the earthquake and Songshan Electromagnetic Station Therefore, the change of apparent resistivity is stronger in all frequency bands, but the change of ρyx is larger than that of ρxy, which is different from that of Yeongdeung earthquake.Furthermore, due to the small number of collected small earthquakes, the time delay of S-wave of fast and slow The result of the analysis did not reflect the accumulation of stress intensity. Another reason may be the result of the earthquake straining together with the stress adjustment after the Yongdeng earthquake (more than 120 km distance).