地磁与地电混合观测台地磁的地电测数干扰处理方法

A Processing Method of Geoelectric Counts Interference for Mixed Observation Station of Geomagnetic and Geoelectric Measurements

我国地震前兆观测台网中地磁与地电观测仪器经常相距很近。而地电台每小时加电观测一次,由于电磁感应,使得地磁观测资料有间隔为1小时的高频干扰,使得地震前兆信息或其他地球物理过程产生的异常信息在地磁数据分析中难以分辨。经过分析这些干扰信息特点,提出了采用Fourier变换在频率域中将高频干扰进行滤除和采用与典型干扰波形相关的方法去除地电测数干扰,该文对安徽蒙城地震台的观测资料的处理结果表明了方法的有效性。很多中国大陆地震前兆观测台具有类似的干扰,因此该方法具有一定推广价值。

In the earthquake precursor observation network of China, geomagnetic and geo- electric observation instruments are usually closely placed. The high frequency interference to geomagnetic observation data with a period of one hour, which is caused by the electromagnetic induction due to the electrifying operation once an hour during geoelectric observation, will make earthquake precursor and other anomalous geophysical information difficult to be distinguished from the geomagnetic data. The characteristics of this interfer- ence information were analyzed in this paper. In order to eliminate the interference, the methods of filtering the high frequency interference in frequency domain by Fourier trans- form and the typical interference waveform correlation were proposed, respectively. Final- ly, the effectiveness of our methods was proved by applying to the observation data of Mengcheng station of Anhui province. THis method is applicable to many earthquake precursor observation stations in China.