In this paper, presentation of specific features of TEC behaviour as a possible
precursor of Orkney earthquake of August 5th, 2014 (M5.5) was made. To achieve this,
TEC data from Suth station and GIM TEC maps were used. The period understudied (prior
to and after the earthquake) experienced quiet geomagnetic situation which made
the analysis much easier. A characteristic anomaly was noticed from 4 days before
the earthquake and it was found out that the day-time TEC increases significantly and consistently relative to the background
condition up to the day before the earthquake. To reveal the spatial dimensions
of seismo-ionospheric anomaly longitudinally, the maps from IONEX database were
used. The ionosphere, experiencing a modification as an increase of electron concentration
over a large area, was revealed.
Cite this paper
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