太陽活動が地震を誘起する可能性を示した論文が2026年2月3日に出版されました。(2026年2月4日)

論文の書誌情報:

Authors: Akira Mizuno, Minghui Kao, Ken Umeno*

Title: Possible mechanism of ionospheric anomalies to trigger earthquakes – Electrostatic coupling between the ionosphere and the crust and the resulting electric forces acting within the crust –

International Journal of Plasma Environmental Science and Technology, Vol. 20, No. 1, e01003 （オンライン出版日:2026年2月3日(火曜日))

論文DOI: https://doi.org/10.34343/ijpest.2026.20.e01003

*責任著者

Abstract:

This study proposes a capacitive coupling model between the Earth’s crust and the ionosphere to explain ionospheric anomalies observed prior to major earthquakes and to explore their potential role in triggering seismic events. In this model, a fractured zone within the crust acts as a capacitor, accumulating electric charge through the infiltration of hightemperature, high-pressure water containing dissolved ions. The precipitation of ultrafine charged particles within the fracture zone generates an electric field that interacts with the ionosphere, leading to anomalies such as increased total electron content (TEC), lowered ionospheric altitude, and reduced propagation velocity of medium-scale traveling ionospheric disturbances (MSTIDs). The model further suggests that the ionosphere can exert electrostatic forces on the crust via capacitive coupling. Specifically, negative space charges formed in the lower ionosphere?often enhanced by solar flares?can induce electric fields within crustal voids, generating electrostatic pressure sufficient to promote void collapse and large-scale fracturing. Quantitative estimates indicate that ionospheric disturbances with TEC increases of 10?90 units can produce pressures up to several MPa within crustal voids, comparable to gravitational and tidal forces. The coincidence of strong solar flare activity with the 2024 Noto Peninsula earthquake supports the hypothesis that ionospheric charge variations may contribute to earthquake initiation. This mechanism provides a novel perspective on the interaction between atmospheric and lithospheric systems and suggests that monitoring ionospheric conditions could enhance earthquake forecasting capabilities. By integrating geophysical, atmospheric, and electrostatic principles, this work highlights the significance of ionosphere?crust coupling and its implications for seismic hazard assessment. The findings underscore the need for further interdisciplinary research to validate the proposed mechanism and to refine predictive models for earthquake precursors.

Keywords – Capacitive coupling model, solar flare-induced TEC variations, triggering an earthquake, electrostatic forces, ionospheric anomalies.