An Investigation into the Seismicity and Crustal Structure of Northern Aegean Using Data Recorded by the Hellenic Unified Seismic Network (Husn)

The tectonics of northern Aegean are affected by the westward push of the Anatolia plate and the gravitational spreading of the Aegean lithosphere that promote transtensional deformation in the area. As a result of these processes several destructive earthquakes occur in northern Aegean, the latest of them in June 2017 when a Mw 6.3 event caused extensive damage and one casualty in the island of Lesbos. This proposal aims at relocating a total of 6,700 events that were recorded in this area during 2011-2017 by stations of the Hellenic Unified Seismic Network (HUSN) and strong-motion sensors. First, a minimum 1D velocity model will be derived using the algorithm VELEST and constrained absolute locations will be obtained using NLLOC, a nonlinear probabilistic location code. In order to further enhance these results, precise relative locations will be also calculated using the doubledifference algorithm HYPODD. It is expected that these results will significantly help routine earthquake location in northern Aegean and will also contribute towards delineating seismogenic faults that lie offshore and cannot be detected by field studies. If time allows this work will also include a tomographic inversion of travel times using the code LOTOS, for the purpose of elucidating the crustal structure of the area.