magnetic declination 地磁偏角 ; [地物] 磁偏角 ; 磁力偏差 ; 磁差

magnetic declination diagram 磁偏角略图

Movement of Magnetic Declination 并做成动画

MAG DEC Magnetic Declination 磁偏角 ; 磁偏移

map magnetic declination 图幅磁偏角

magnetic declination angle [地物] 磁偏角

measured magnetic declination 磁偏角实测值

expected magnetic declination 磁偏角期望值

Magnetic Declination Calculator 磁偏角计算器

Magnetic declination variometers 磁偏角磁变仪