Seismic structure of African slab beneath Antalya bay southern Turkey

Abstract

In this passive seismic tomography study, we examined the seismic structure of the African slab beneath the Antalya coast, extending from the Isparta Angle to the island of Cyprus, using regional data. The southern part of Turkey, adjacent to the Mediterranean Sea, has a highly complex structure due to a wide range of tectonic and geodynamic processes, contributing to the high seismic activity of the region. We collected a 14-year data catalog from AFAD (T. C. Ministry of Interior Disaster and Emergency Management Department Earthquake Department Directorate). The resulting dataset contained the arrival times of 66,805 P-waves and 46,197 S-waves from 6158 events, which were used to produce high-resolution seismic tomography models down to 120 km depth. The results revealed a low-velocity anomaly beneath the Paphos fault at a depth of approximately 70 km, which may indicate a rupture between the Cyprus and Antalya slabs. Moreover, the Antalya slab seems to become thinner at this depth. The structure of the continental crust of the Anatolian Plate under the Central Taurus Mountains is characterized by two anomalies: an upper high-velocity and a lower low-velocity one. This indicates the heating of the lower crust from the ascending asthenospheric flow penetrated through the gap between the Antalya and Cyprus slabs. The research findings made it possible not only to clarify the structure of the African slab beneath the Antalya coast, but also to detect local heterogeneities not investigated previously.