Soil radon and ionospheric TEC anomalies before the 2022 M6.8 Chihshang Earthquake in eastern Taiwan

Ching-Chou FU; Hau-Kun Jhuang

講演情報

[E] 口頭発表

セッション記号 M (領域外・複数領域) » M-IS ジョイント

[M-IS04] Interdisciplinary studies on pre-earthquake processes

2024年5月26日(日) 15:30 〜 16:45 301B (幕張メッセ国際会議場)

コンビーナ:服部克巳(千葉大学大学院理学研究科)、劉正彦(国立中央大学太空科学研究所)、Ouzounov Dimitar(Center of Excellence in Earth Systems Modeling & Observations (CEESMO) , Schmid College of Science & Technology Chapman University, Orange, California, USA)、Huang Qinghua(Peking University)、座長:Ouzounov Dimitar(Center of Excellence in Earth Systems Modeling & Observations (CEESMO) , Schmid College of Science & Technology Chapman University, Orange, California, USA)、Jann-Yenq G Liu(National Central University)

15:45 〜 16:00

[MIS04-12] Soil radon and ionospheric TEC anomalies before the 2022 M6.8 Chihshang Earthquake in eastern Taiwan

★Invited Papers

*Ching-Chou FU¹、Hau-Kun Jhuang¹ (1.Institute of Earth Sciences, Academia Sinica)

キーワード：radon, TEC, Chihshang earthquake

We present a critical analysis of the observations and interpretations related to the 2022 Chihshang earthquake that occurred on September 17, 2022, in eastern Taiwan. This work comprehensively investigated the different parameters related to the lithosphere and ionosphere, including soil radon gas and total electron content (TEC). The previous significant increases in soil radon were often detected at CS station before the large earthquake, which occurred in eastern Taiwan along the southern Longitudinal Valley, suggesting that anomalies in radon provide a good indicator for exploring earthquake precursors in this region. The result shows significant increases in soil radon were found one month before the earthquake. The persistence of the TEC anomalies from September 5 to 12, which were identified by two different methodologies around the Taiwan area to be the pre-earthquake signals, was observed. Furthermore, a higher value of CO2 flux in the area was found after the earthquake, which can be interpreted as an extra contribution of the gas sources from depth or the increased permeability of the fault system. These joint observations have revealed that all these anomalies are considered short-term precursors, which can be explained by the theoretical mechanism of lithosphere–ionosphere coupling (LIC).