乌鲁木齐台地磁短周期变化与邻区地震

GEOMAGNETIC SHORT-PERIOD VARIATION AT URUMQI STATION AND THE EARTHQUAKES IN THE NEIGHBOURING AREA

利用转换函数方法计算处理了乌鲁木齐台 1990年 1月～ 1997年 12月地磁短周期 T为 9～2 0 0 min的复转换函数 A、B之模 |A|、|B|、总方差 σZ以及帕金森矢量 ,并对其在乌鲁木齐地区 2 50km范围内 15次 4 .0～ 5.7级地震发生前后的变化进行了研究。结果表明 :不同周期的转换函数 A、B以及总方差 σZ值在震前均有明显异常。

Based on the geomagnetic data observed at Urumqi Seismostation from Jan.1990 to Dec.1997,the modulus ｜A｜,｜B｜of complex transfer characteristic A,B of geomagnetic short period T(T between 9 and 200 min),total variance σ Z and Parkinson's vector are calculated by using transfer characteristic method.Meanwhile,their variation before and after 15 earthquakes ranging from magnitude 4.0 to 5.7 within an area 250 km from Urumqi Station are studied.The result shows that A,B of different periods and σ Z are anomalous obviously before the earthquakes.