地电场观测典型干扰数据的修正方法

Correction methods on typical interference data of geoelectric observation

研究由于线路故障、直流供电等干扰因素引起的地电场数据变化,尝试使用带阻滤波、经验模态分解等方法排除干扰。处理结果表明,上述方法可以减少干扰因素的影响,有利于提取地震前兆信号。

In order to distinguish seismic precursory information, three interfernce types of the geoelectric field variation affected by line fault, power supply etc. We eliminate interference with the method of empirical mode decomposition, bandstop filter etc. The result shows that with this method, useful information can be provided for seismic precursory information and better effect can be obtained. We analysis HHT time-frequency spectrum observed at the stations around the epicenter of Wenchuan after the interference factors have be removed. The result shows that the increased power spectrum was recorded at Xiaomiao and Hugu Seismic Stations on May 12, 2008.