25 EYLÜL 2024 YUMRUKAYA-TATVAN (Mw=4.6) DEPREMİNİN BİTLİS’İN GELECEK DEPREM POTANSİYELİ ÜZERİNE ETKİSİ

<p class="MsoNormal" style="margin-top:10.0pt;text-align:justify;line-height:115%"><span lang="EN-US">The Anatolian Plate onthe Alpine-Himalayan Orogenic Belt is the most active belt following thePacific Seismic Belt and is recognized for its earthquakes characterized bytransform faulting mechanisms. In recent years, strong/destructive earthquakes suchas the 1999 İzmit earthquake (Mw = 7.6), the 2020 Elazığ earthquake (Mw=6.8),and the 2023 Kahramanmaraş earthquakes (Mw=7.7 and Mw=7.6) have occurred notablealong the North Anatolian Fault Zone (NAFZ) and the East Anatolian Fault Zone(EAFZ). Besides these primary fault zones, the relative movements of theArabian, Eurasian, and Anatolian Plates in the Eastern Anatolia region, alongwith the deformation of the Bitlis-Zagros Suture Zone, contribute to additionaltectonic activity and seismicity in this region. The October 23, 2011, Vanearthquake (Mw=7.2) and its ongoing aftershocks underscore significant tectonicactivity linked to the compression regime that developed east of Lake Vanbasin. While the western part of the Lake Van basin might not be as prominentas the eastern part, it still contains fault and fault zones capable ofgenerating significant medium-magnitude earthquakes. In this context, theSeptember 25, 2024, Yumrukaya-Tatvan earthquake (Mw = 4.6) serves as a criticalindicator for understanding the seismicity of Bitlis province and itssurrounding areas. This earthquake occurred near the Kavakbaşı fault,displaying a strike-slip mechanism. However, the General Directorate of MineralResearch and Exploration’s active fault map shows no active fault and faultzone at the epicenter of the Yumrukaya-Tatvan earthquake (Mw = 4.6). This studyanalyzes the epicenter locations of the September 25, 2024, earthquake and itsaftershocks, examines the Coulomb stress transfer map, and assesses the <i>b</i>-valuechange that illustrates the relationship between magnitude and earthquakefrequency to identify the fault in the region associated with the Yumrukaya-Tatvanearthquake. Regionally, small <i>b</i>-values(&lt;0.8) were observed in the north of the South Anatolian Thrust Belt</span>,Muş Fault Zone, and west of Van Lake. <span lang="EN-US">Positive stress transfer, focal mechanism solutions of earthquakes, andthe directions of earthquake epicenters indicate a movement from the Kavakbaşıfault in the west toward the South Anatolian Thrust Belt in the east/southeast.Therefore, the Yumrukaya-Tatvan earthquake is a crucial indicator forpredicting the future seismicity of the region.<o:p></o:p></span>