汶川地震前地脉动低频波动现象及其应用的初步研究

通过对距离汶川地震余震区较近的武都地震台震前连续记录资料的傅里叶频谱特征分析,发现在震前临震阶段,频率为0.1～0.3Hz的地脉动幅值出现快速、持续地增大现象;连续跟踪观测和试验表明,该现象在2008年7～9月间发生的多次地震前在多个台站出现,这种现象具有重现性,在时间上具有持续性,在空间上由震中及其附近或某个"位置"向外围扩散.对该特殊频率波动的物理本质、与震源和孕震动力学过程的关系等研究有可能对临震预测具有意义.

Preliminary Study and Application on the Tremors with Lower Frequency Recorded by Seismograph Before the Wenchuan Earthquake

Through the analysis of Fourier spectrum of the continuous record at Wudu Seismological Station near the aftershock zone of the Wenchuan earthquake, it is found that the amplitude within 0.1 ～0.3 Hz increased rapidly just before the Wenchuan earthquake. Further real time observation shows that such phenomenon was observed by various stations before several aftershocks happened from July to September, 2008, exhibiting repeatability in phenomenology. Study on the physical nature of the special fluctuation, its relationship with the earthquake occurrence and the seismogenic dynamic process could be of significance to the short-imminent earthquake prediction.