Seismic attenuation transients reveal progressive crustal modification before and during the 2023 Türkiye earthquakes

Abstract

Abstract We present the first spatiotemporally resolved separation of scattering and intrinsic seismic attenuation across the East Anatolian Fault Zone, capturing their evolution before and during the 2023 Türkiye earthquake doublet. Our results reveal a fault-segment–dependent decoupling between scattering and intrinsic absorption, indicating that the two components are governed by distinct physical processes rather than a single attenuation mechanism. Scattering attenuation intensified along the Çardak-Sürgü rupture, delineating spatial variations associated with strong rheological contrasts, whereas intrinsic attenuation exhibits broader temporal variability. Time-series analysis identifies measurable attenuation changes, reaching up to ~ 40%, associated not only with the mainshocks but also with moderate pre-sequence seismicity. These observations indicate that seismic attenuation records a temporal fingerprint of evolving crustal conditions. Overall, our findings demonstrate that resolving attenuation components provides diagnostic capability by capturing crustal modifications beyond the general post-earthquake damage observation.