地脉动记录中台风扰动和低频波前兆信息的频带区别研究

Research on Frequency Difference between Typhoon Disturbance and Precursor Information of Low Frequency Wave in Microtremor Recordings

通过对宽频带数字资料在昆仑山口西8.1级、汶川8.0级、民乐-山丹6.1级地震前地脉动幅度和频谱变化的研究,发现在震前几天地脉动有明显的扰动变化,初步认为是大震的低频波前兆异常.而强台风对地脉动也有类似的扰动现象.从频率域对比研究后初步认为：低频波前兆异常的可能频带范围是0.1～0.14 Hz,而强台风对地脉动的扰动频率范围是0.15～0.30 Hz.区别对待这两个频带,对跟踪强震临震异常有现实意义.

Through studying the amplitude and spectral change of microtremor before the west to Kunlun Mountain Pass Ms8.learthquake,Wenchuan Ms8.0 earthquake and Minle-Shandan Ms6.1 earthquake based on the broadband digital data,we found that the microtremor disturbance changed obviously in a few days before the earthquake,which might be the low-frequency wave precursory anomalies before the large earthquake,and the strong typhoon has the similar disturbance to the microtremor.From the comparison of frequency domain of typhoon disturbance and precursor information of low frequency wave,we obtained that the frequency range of low-frequency wave precursor anomaly is 0.1 ～0.14 Hz,and the disturbance frequency range of strong typhoon on the microtremor is 0.15 ～0.30 Hz.To distinguish these two bands has the realistic significance to tracking the impending earthquake anomaly of the strong earthquake.