本文利用1958 ~ 1995年已正式出版的《地磁观测报告》资料对广州地磁台地磁场的长期变化进行分析研究。
According to the observation data at Guangzhou geomagnetic observatory from 1958 to 1995, we summarize the laws of the geomagnetic secular variation in Guangzhou geomagnetic observatory.
测区内未发现有局部地磁长期变化异常。
No anomalous local secular geomagnetic variation has been found in the area.
利用地磁场模型资料，计算和分析了公元0 ~ 2000年的地磁场偶极子磁矩和地磁北极位置的长期变化。
With geomagnetic field model records, several kinds of secular variation of geomagnetic dipole moment and the position of the geomagnetic North Pole during the year 0 ~ 2000 a.
利用河北省地磁台1986 ~ 2005年的地磁观测资料，对该地区地磁场长期变化规律进行总结分析。
According to observation data at geomagnetic stations in Hebei Province from 1986 to 2005, we sum up and analyze the laws of the geomagnetic secular variation in this paper.
用国际参考地磁场模型（IGRF）分析了地磁场能量在地球内部的分布及其长期变化。
The eighth generation of the International Geomagnetic Reference Filed (IGRF)is used to study distribution of geomagnetic energy in the Earths interior and its secular variations.
用国际参考地磁场模型（IGRF）分析了地磁场能量在地球内部的分布及其长期变化。
The eighth generation of the International Geomagnetic Reference Filed (IGRF)is used to study distribution of geomagnetic energy in the Earths interior and its secular variations.
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