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The 2023 Türkiye earthquake sequences are among the most devastating events of recent years. The earthquake occurred on February 6th, 2023 and was characterized by several foreshocks starting from 1:17UT. The Mw 7.8 shock was the strongest and was caused by a shallow strike-slip faulting.We applied the Total Variometric Approach (TVA) methodology to fully characterize the 2023 Turkey earthquake sequences from ground to the ionosphere [1].The TVA technique simultaneously employs two variometric algorithms, VADASE (Variometric Approach for Displacement Analysis Stand-alone Engine) and VARION (Variometric Approach for Real-Time Ionosphere Observation), to retrieve earthquake ground shaking, co-seismic displacements and ionospheric Total Electron Content (TEC) variations in real-time. TVA was already successfully applied to the 2015 Mw 8.3 Illapel earthquake and tsunami.In this case, we used IGS observations from 6 GNSS located in Turkey, Greece and Israeli and data from 60 GNSS receivers belonging to the Turkish network TUSAGA-Akitf [2].Our first results show very strong ground shaking up to 10 cm/s in the East direction and up to 25 cm in the North direction. We notice great displacements especially in the horizontal plane (up to 30 cm). This is coherent with a strike-slip earthquake. Nonetheless, we also observe great displacements in the Up component (up to 1m). This could be the reason why we see this earthquake signature also in the ionosphere, although it is a strike-slip shock.Indeed, preliminary ionospheric analyses reveal the signature of acoustic-gravity waves epicenter (AGWepi) especially for satellites G03, G04, G31 and E09.A 30cm tsunami wave was also registered in Erdemil, along the Turkish coastline.This study shows how the TVA can contribute to the complete understanding and rapid characterization of the seismic event, from ground to the atmosphere, and to manage and real-time earthquake hazard assessment.[1] Ravanelli, M., Occhipinti, G., Savastano, G., Komjathy, A., Shume, E. B., & Crespi, M. (2021). GNSS total variometric approach: first demonstration of a tool for real-time tsunami genesis estimation. Scientific Reports, 11(1), 1-12.[2] https://www.tusaga-aktif.gov.tr/ |
