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

[MIS04-08] Spatial analyses on seismo-ionospheric anomalies of total electron content before the
6 February 2023 M7.8 and M7.5 Turkey Earthquakes

★Invited Papers

*FU-YUAN CHANG¹, Yun-Cheng Wen², Chi-Yen Lin¹, Yuh-Ing Chen³, Chi-Kuang Chao¹, Ching- Chung Cheng⁴ (1.Center for Astronautical Physics and Engineering, National Central University, Taiwan, 2.National Central University, Taiwan, 3.Graduate Institute of Statistics, National Central University, Taoyuan City, Taiwan, 4.Department of Space Science and Engineering, National Central University, Taoyuan City, Taiwan)

Keywords:earthquake, seismo-ionospheric anomalies, FORMOSAT-5

On 6 February 2023 at 01:17 UTC, an M7.8 earthquake occurred in South-Eastern
Turkey (37.2°N 37.0°E, 10.0 km depth), and several strong aftershocks have also
been observed in the region, notably a magnitude M7.5 (38.0°N 37.2°E, 10 km depth)
at 10:24 UTC the same day. Spatial analyses of the total electron content (TEC) of
the global ionosphere map (GIM) are employed to observe the latitude-longitude
distributions of seismo-ionospheric anomalies (SIAs) during January-February 2023.
A global search of 5183 (=73x71) lattices shows that SIAs of significant TEC
increases specifically appear near the epicenter on day 24-22 (12-16 January) and 2-0
(4-6 February) before the two earthquakes. The ion density and ion velocity
measured by the science payload of Advanced ionospheric Probe (AIP) onboard the
FORMOSAT-5 (F5) satellite and the EIA (equatorial ionization crest) distances
between northern and southern hemispheres of GIM TEC are used to find the
ionospheric electric fields over the epicenter area during the two periods of 12-16
January and 4-6 February 2023.