选取2008年4月27日—5月13日河南及邻区宽频带地震资料，对全球3次M ≥7.0地震前地脉动时域、频域、幅值进行分析，发现地震前2.4—3.6天地脉动出现低频异常，幅值与震级、震中距有关；前两次地震前低频异常优势频率分布在0.20—0.30 Hz，而汶川8.0级地震前两个频段显示异常，分析认为，0.18—0.25 Hz 频段异常与台风扰动有关，0.11—0.18 Hz 频段异常与汶川地震相关。分析近海台风对地脉动的影响，发现台风期间，0.15—0.25 Hz 频段地脉动显示异常，幅值变化与台风过程基本同步。%For the broadband seismic data from April 27 to May 13,2008 in Henan Province and its adjacent area,the 3 acuity M 7.0 earthquakes official pulse time domain,frequency domain and amplitude analysis study found that three times before the quake to 2.4 d,3.6 d abnormal low frequency pulse,amplitude related to magnitude,epicentral distance; Two earthquakes before the abnormal low frequency advantage at 0.20 - 0.30 Hz frequency distribution,and the Wenchuan earthquake showed abnormal,the first two frequency analysis that 0.18 - 0.25 Hz frequency anomalies associated with typhoon disturbance,0.11- 0.18 Hz frequency anomalies related to the Wenchuan earthquake is more. Through offshore typhoon on the influence of the pulse,the study found during the typhoon to 0.15-0.25 Hz frequency pulse display abnormal,the spectrum amplitude change and the typhoon process has a good synchronization.
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