Year: 2025
Type: article
Abstract: At 23:58:08 UT on April 2, 2024, an M7.4 earthquake occurred near Hualien, Taiwan region, triggering geomagnetic variations. Seismic waves typically induce geomagnetic disturbances that exhibit time delays that are dependent on epicentral distance in previous studies. In this study, simultaneous perturbations in three-component geomagnetic field were observed within 114 km of the epicenter. The out-of-phase perturbations in the Z-component between the geomagnetic stations near the epicenter suggest a local electric current triggered by the earthquake. The height and orientation of the currents were estimated to be approximately 99 km and 247 ° (southwest), respectively. The magnetic field and high-frequency Doppler sounder observations indicate that acoustic waves are triggered by the earthquake. This was consistent with the sound propagation of the NRLMSISE−00 atmospheric model. The acoustic waves propagate from the ground to ionosphere, causing plasma to move across the Earth’s magnetic field, which leads to the generation of electric current. This study suggests that earthquake-triggered acoustic waves can change the dynamics of the ionosphere. These findings provide new insights into earthquake-ionosphere coupling, indicating that earthquakes can trigger temporal ionospheric currents near the epicenter.
Institutions: China University of Geosciences, China University of Geosciences (Beijing), Chengdu University of Technology, State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, National Central University, Southern University of Science and Technology, Central Weather Administration, Hefei University of Technology, University of Warmia and Mazury in Olsztyn, Institute of Earth Sciences, Academia Sinica, Academia Sinica, China Earthquake Administration
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,790
Awards: G5577408881, G8712628158
OpenAlex ID: W4417037899