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arXiv · 1407.1488

Dynamics of vertical ionospheric inhomogeneities over Irkutsk during 06:00-06:20UT 11/03/2011 caused by the Tohoku earthquake

Oleg I. Berngardt·G. V. Kotovich·S. Ya. Mikhailov·A. V. Podlesny
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Abstract

According to the data of quasi-vertical sounding at Usolie-Tory path (midpoint - 52.3N, 103E, 120km distance), the dynamics of vertical structure of the midscale inhomogeneities of the plasma frequency was reconstructed. These irregularities are caused by Tohoku earthquake 11/03/2011 (38.3N, 142.4E). Observed horizontal velocities of propagation in the ionosphere and the spatial scales of the wave-like disturbance modes, generated by earthquakes, are calculated. As a result of numerical simulation involving the data from TALAYA seismic station (TLY, 51.7N, 103.7E) and comparison with the experiment it is shown that the vertical ionospheric irregularities of 5-40km range observed in first 20 minutes after the beginning of observations of effects (from 06:00 to 06:20 UT) are qualitatively explained by travelling of acoustic shock wave cone ( Mach cone ) from supersonic ground source - seismic wave to the heights up to 200km. It is shown that the most likely source of the shock wave were Z and E components of the seismic oscillations observed at TLY station. Irregularities observed after 06:20UT were apparently linked with other mechanisms. It is shown that the existing temporary CHIRP ionosonde temporal resolution (60 seconds) and the ionogram inversion technique used are not enough for detailed diagnosis of fine spatial vertical structures of this process.

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BibTeXRIS

Oleg I. Berngardt, G. V. Kotovich, S. Ya. Mikhailov, A. V. Podlesny. 2014-07-06. Dynamics of vertical ionospheric inhomogeneities over Irkutsk during 06:00-06:20UT 11/03/2011 caused by the Tohoku earthquake. https://doi.org/10.1016/j.jastp.2015.07.004

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