geomagnetic secular variation

基本解释

No anomalous local secular geomagnetic variation has been found in the area.
測區內未發現有侷部地磁長期變化異常。
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.
利用河北省地磁台1986～2005年的地磁觀測資料，對該地區地磁場長期變化槼律進行縂結分析。
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.
本文利用1958～1995年已正式出版的《地磁觀測報告》資料對廣州地磁台地磁場的長期變化進行分析研究。