Unusual Sunset Terminator Behaviour of Vlf Signals at 17khz during the Earthquake Episode of Dec., 2004
نویسندگان
چکیده
We have been monitoring VTX station at 17KHz from the Centre for Space Physics VLF receiver. While everyday we receive the socalled classic patterns of sunrise and sunset, we started observing irregular behaviour of the local terminators from December 22nd, 2004 onward and it continued till the 30th of December, 2004. It is to be recalled that the devastating Tsunami occurred on the 26th of December, 2004 due to an earthquake 9.0 Richter scale and there were several aftershocks at the level of 6.0 or more in the Richter scale in the next few days which followed. The terminator times shifted towards the night. We suspect that these abnormal behaviours could be due to movements of the ionospheric layer as pointed out by Prof. Hayakawa in his observations in Japan.
منابع مشابه
On the generation mechanism of terminator times in subionospheric VLF/LF propagation and its possible application to seismogenic effects
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