1.磁照图的认识磁照图记录的是地球磁场 H、D、Z 三个分量24小时的变化过程,如图(1)所示。从图上可以看见七条记录曲线。每个分量各两条,一条反映地磁场变化,简称变线;另一条是量图用的基准线,简称基线。水平分量的变线、基线分别用字母 H 和 H_B 表示;偏角的变线、基线分别用字母 D 和 D_B 表示,垂直分量 1. Magneto-graph recognition Magnetograph records the magnetic field H, D, Z three components 24 hours of change process, as shown in Figure (1) below. From the map you can see seven record curves. Each of the two components, one reflecting changes in the Earth’s magnetic field, referred to as a change line; the other is the use of the baseline figure, referred to as the baseline. Change the horizontal component of the line, respectively, with the letters H and H_B baseline; declination of the line, respectively, with the letters D and D_B baseline, the vertical component