崇明异常电磁扰动与台湾7.5级强震

The electromagnetic anomalies observed at Chongming station and the Taiwan strong earthquake (M=7.5, March 31, 2002)

2002年3月31日14时52分在台湾以东海中发生7.5级强地震,地震发生前后上海市地震局崇明地震台电磁波仪器记录到了一系列强烈电磁辐射异常信息,其中震前最早的信息出现在24天前,最迟的信息出现在震前5小时且幅度最大。主震发生前电磁辐射异常信号的振荡幅度随着主震临近而增大,主震发生后又降了下来。余震期间的电磁辐射异常信息也十分丰富。文中探讨了这些电磁辐射异常信号与强震之间的关系,结合多种震例的记录认为这类震前电磁辐射异常信号可作为临震前的一种信息。为认识和丰富震前电磁辐射前兆异常的现象与研究增加了新的内容。

A series of electromagnetic anomalies have been detected at the Chongming station in ultra-low frequency band (ULFB) before the Taiwan earthquake (M=7.5, March 31, 2002) with the following characteristics. The earliest electromagnetic anomalies appeared in advance of 24 days before the earthquake, and the latest appeared in advance of 5 hours before the mainshock, whose amplitude is largest. The amplitudes of the electromagnetic anomalies increased gradually approaching the mainshock and decreased after the mainshock again. The abundant information of the electromagnetic anomalies appeared in advance of many aftershocks. This paper mainly discusses the relation between the electromagnetic anomalies and the strong earthquakes. The analysis reveals that the properties of the preseismic electromagnetic anomalies might be considered as signatures of an impending earthquake.