Desplazamiento regional en Malatya y alrededores (este de Anatolia) provocado por los terremotos de Kahramanmaraş del 6 de febrero de 2023 (Mw 7,7, Mw 7,6)

On February 6, 2023, two major earthquakes (Mw 7.7 and Mw 7.6) struck Kahramanmaraş, significantly affecting Eastern Anatolia. The tectonic structure of Malatya and its surroundings, including the East Anatolian Fault Zone (EAFZ) and the Malatya Fault, plays a crucial role in the region's seismicity. Following the Kahramanmaraş earthquakes, two moderate earthquakes (Mw 5.3 and Mw 5.0) occurred in Malatya in August 2023, causing panic among the locals. GNSS data from Continuously Operating Reference Stations-Turkey (CORS-TR) were analyzed in this study to investigate the tectonic activity in and around Malatya and assess how the stress accumulated after the February 2023 earthquakes may have influenced this region. Firstly, the displacements in Eastern Anatolia between January 1 and March 1, 2023, were calculated to evaluate the immediate effects of the February 6 earthquakes. Then, GNSS data from March 2 to December 31, 2023, were processed to examine the ongoing tectonic behavior. Additionally, seismic activity during the same period was analyzed, revealing the occurrence of several moderate earthquakes potentially linked to the February 6, 2023 Kahramanmaraş earthquakes. The GNSS results indicate that most stations show continued tectonic motion, suggesting that stress changes induced by the Kahramanmaraş earthquakes still influence the region. Furthermore, the lack of stabilization at the stations highlights the persistence of postseismic deformation. The spatial correlation between observed seismicity and displacement vectors emphasizes that the Malatya segment of the EAFZ remains a significant zone of strain accumulation and release. Stations such as MLY1 (Malatya), APK1 (Arapgir, Malatya), and ADY1 (Adıyaman) continued to move in the same direction observed during the mainshock, pointing to ongoing afterslip. Moreover, stations farther from the rupture zone (e.g., SUF1 (Sanlıurfa), HAT2 (Hatay), GURU (Gürün, Sivas)) exhibited consistent displacement patterns, indicating that postseismic deformation extended across a broad area, including the Arabian Plate and the back-arc region north of the fault. These findings underline the long-term impact of the February 6, 2023, earthquakes on regional seismic activity and demonstrate the importance of integrating geodetic and seismic data for ongoing hazard assessment in Eastern Anatolia.