The RTL Anomaly of Seismicity before the February 6, 2023 Earthquake in Turkey

• Published in: Izvestiya. Physics of the solid earth Vol. 59; no. 6; pp. 929 - 938
• Main Authors: Smirnov, V. B., Petrushov, A. A., Mikhailov, V. O.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.12.2023; Springer Nature B.V
• Subjects: Anomalies; Catalogues; Earth and Environmental Science; Earth Sciences; Earthquake damage; Earthquakes; Geophysics/Geodesy; Seismic activity; Seismicity; Iran; Turkey; seismic anomalies; Pazarcik earthquake; seismicity
• ISSN: 1069-3513; 1555-6506
• DOI: 10.1134/S1069351323060204

—Based on the data from the regional Turkey earthquake catalog and the ANSS Comprehensive Earthquake Catalog for Turkey and a part of Iran, a posteriori analysis of RTL anomalies of seismicity before the damaging M w 7.8 Pazarcik earthquake in Turkey of February 6, 2023 and, for comparison, before the M w 7.1 earthquake of October 23, 2011 (Eastern Turkey), the M w 7.3 earthquake of November 12, 2017 (Iran), and the М 6.7 earthquake of January 24, 2020 (the East Anatolian Fault), was made. Distinctly observable before the Pazarcik earthquake is an RTL anomaly with well-marked stages of a seismic quiescence and subsequent activation near the epicenter of the future earthquake. Spatially, the anomaly is one-and-a-half times smaller than the source of the Pazarcik earthquake, and one-and-a-half—two times smaller than RTL anomalies before other regional earthquakes with a magnitude above 7. By size, it corresponds to the anomaly before the M w 6.7 earthquake that occurred on the same fault. As a hypothesis to explain why the size of the anomaly before the M w 7.8 Pazarcik earthquake does not match the sizes of the anomalies characteristic of M 7+ earthquakes, it was assumed that the detected RTL anomaly reflects the formation only of the first, relatively small segment of the source of the Pazarcik earthquake.