研究变化磁场的基本特征,对于鉴别震磁效应、确定震磁异常都是十分必要的。变化 磁场主要有长期变与日变化两种。消除长期变的 影响,通常是将每个测点的观测值与标准地磁台 的观测值比较,并利用等磁变图作出校正。对地 磁日变化,目前都采用磁测点和标准台的同时观 Studying the basic characteristics of the changing magnetic field is very necessary for identifying the seismic magnetic effect and determining the seismic magnetic anomaly. The main changes in the magnetic field has two long-term changes and changes. Eliminating the effects of long-term changes, it is common to compare the observations at each measuring point with observations from a standard geomagnetic station and make corrections using isomagnetic maps. On the geomagnetic day-to-day changes, the current use of magnetic measuring point and the standard station at the same time concept