Ionospheric F2-layer Perturbations Observed After the M8.8 Chile Earthquake on February 27, 2010, at Long Distance from the Epicenter

Abstract

The F2-layer critical frequency (foF2) data from several ionosondes are employed to study the long-distance effect of the M8.8 Chile Earthquake of February 27, 2010, on the F2 layer. Significant perturbations of the peak F2-layer electron density have been observed following the earthquake at two South African stations, Hermanus and Madimbo, which are located at great circle distances of ~8,000 and ~10,000 km from the earthquake epicenter, respectively. Simplified estimates demonstrate that the observed ionospheric perturbations can be caused by a long-period acoustic gravity wave produced in the F-region by the earthquake.

Time-Varying Seismogenic Coulomb Electric Fields as a Probable Source for Pre-Earthquake Variation in the Ionospheric F2-Layer

“…Effects of earthquakes on the F region ionosphere are documented in many works (e.g. Leonard & Barnes 1965;Row 1966;Calais & Minster 1995;Ducic et al 2003;Artru et al 2004;Astafyeva & Afraimovich 2006;Rolland et al 2011;Maruyama et al 2016;Hegai et al 2017). At the same time, Pulinets & Boyarchuk (2004) refer to numerous observations of abnormal ionospheric variations preceding earthquakes, which were reported before 2004.…”

Seismogenic Field in the Ionosphere before Two Powerful Earthquakes: Possible Magnitude and Observed Ionospheric Effects (Case Study)

“…Among the coupling processes from below, the strong earthquakes are also considered as perturbation sources [6]. The impact of earthquakes on the F-region of the ionosphere has been documented and reflected in many publications [7][8][9][10][11][12][13][14][15]. At the same time, the monograph [6] gives a large number of references to numerous observations (conducted before 2004) of the ionospheric perturbations preceding earthquakes (IPPE), and later examples of the IPPE [16], which could also be ionospheric precursors of earthquakes (IPE) associated with the processes of preparation of earthquakes in the Earth's crust.…”