地磁场日变化的空间差异对流动观测通化结果的影响

通过对中国西部、西南部和东部几组相邻的地磁台站各地磁要素日变幅的对比分析,发现各台站的地磁要素日变化具有空间差异性,这种差异性特征是趋势变化一致而幅度不同.结合一些实例,分析了野外观测资料用相邻的地磁台站的地磁要素数据通化时,通化结果有差异,并且这些差异与观测时间和观测季节关系密切.在实例中,磁偏角（D）、水平分量（H）、垂直分量（Z）及总强度（F）的通化值差异一般分别达到0.5′、6 nT、4 nT、6 nT,这样的差异值有可能影响震情研判.因此,在地震地磁监测工作中的定点连续观测十分重要,而流动地磁观测只应该作为一种补充和辅助手段.

Effect of spatial difference of the diurnal variation of the geomagnetic field on generalizing results of mobile observation

By comparatively analyzing the diurnal variation of geomagnetic elements of several groups of adjacent geomagnetic stations in the West, Southwest and East of China, it is found that the diurnal variations of geomagnetic elements at each station are spatial differences. The characteristics of the difference are that they have the same change trend but not the same amplitude. Combined with some examples, field observation raw materials are analyzed. When the geomagnetic elements of adjacent geomagnetic stations are used for generalizing, there are different results, and these differences are closely related to the time and season of observation. In the examples of this article, the differences of generalized results of magnetic declination (D), horizontal magnetic field vector (H), vertical magnetic component (Z), and geomagnetic total intensity (F) are generally 0.5′, 6 nT, 4 nT, and 6 nT; and such difference values may affect the earthquake situation assessment. Therefore, continuous observation at fixed points is very important in the geomagnetic monitoring of earthquake, and the mobile geomagnetic observation should just be used as a supplement and auxiliary means.