The Determination of Subduction Geometry under the Aegean-Anatolian Plate along Aegean and Cyprean Arcs in the Eastern Mediterranean

Abstract

The southwestern Anatolia is part of the Aegean extensional province, located in a seismically active convergent zone between the African and Eurasian Plates in the Eastern Mediterranean. This region is one of the most active and swiftly deforming domains of the Alpine–Himalayan mountain belt in Turkey. The plate boundary is shaped by the subduction of the African Plate under the Aegean-Anatolian plate consists of the Aegean and Cyprean arcs. The two separate slabs occurred along the plate border related to these arcs. These subducted slabs are separated by a gap beneath Western Anatolia. These arcs intersect in the eastern Mediterranean region and form the tectonic structures, north cusps, the Isparta Angle depending on the subduction. The Isparta Angle caused by the slab is located to the North of Antalya Bay as reverse V shaped. In this study, 3D seismic tomography method was applied to determine the subduction geometry of slabs along the Aegean and Cyprean arcs in the Eastern Mediterranean region. The 3- Dtomographic results obtained by using the arrival times data collected 39,059 earthquakes have revealed concrete results about subduction zones. P wave velocity structure has been compared with the tectonic structures. The tomographic results show that two separate slabs occurred along Aegean and Cyprean arcs. The tear zone between these two slabs is the Fethiye Burdur Fault Zone (FBFZ) and the Astenospheric upwelling occurs in the Fethiye Bay and continues northward from there. It has been determined that there are two slabs dipping to the northeast under the Antalya Bay and to the north under the Gökova Gulf. Based on the tomographic results, it has been determined that the subduction in these region continues to the depth of ~ 100 km. The subducted African lithosphere plays important role in the evolution of southwest Anatolian tectonic structures.