摘要
应用北京及邻区2min采样的地磁总场观测资料,分析了北京台与各临时台地磁总场的频谱特性与频谱幅比的时空变化。结果显示,该地区地磁总场的频谱幅度随周期增大呈下降趋势;各临时台与北京台的频谱幅比具有一定的时空变化,可能与该地区地下电磁结构、地震及构造活动有关。
Based on the data of 2 min geomagnetic total field observation in Beijing and its adjacent areas,the frequency spectrum characteristic and the time-space variation of amplitude ratio of frequency spectrum for Beijing station and other 11 temporal stations are analyzed.The results show that the spectrum amplitude of geomagnetic total field in this area appears decreasing tendency with the increasing of period.The amplitude ratio of spectrum between temporal stations and Beijing station varies with time-space changes,which may be related to the underground electromagnetic structures,earthquakes and tectonic activities in this area.
引文
中国地震局地球物理研究所论著 :0 4AC1 0 2 8.
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