8 January 2013 Mw = 5.7 North Aegean Sea earthquake and its seismotectonic significance

The deformation of the North Aegean Sea is mainly controlled by the westernmost segments of North Anatolian Fault System. On 8 January 2013, a moderate earthquake (Mw=5.7) occurred in the North Aegean Sea. A series of aftershocks were occurred within four months following the mainshock, which have magnitudes varying from Ml=0.9 to 5.0. We have obtained a total of 23 earthquake moment tensor solutions that belong to the 2013 earthquake sequence. The source of this earthquake sequence is a N75 degrees E trending pure dextral strike-slip fault. The temporal and spatial distribution of the earthquakes indicate that the rupture unilaterally propagates from SW to NE. The stress tensor analysis shows that the direction of the regional compressive stress is WNW-ESE. The 1968 Aghios earthquake (Ms=7.3) and the 2013 North Aegean Sea earthquake sequences indicate that the regional stress has been transferred from SW to NE in this region. The 1672 Bozcaada earthquake (M=7.0) had been occurred to the north-east of the 2013 earthquake sequence. The elapsed time (342year) and the regional stress transfer point out that the 1672 earthquake segment is probably a seismic gap and it is a potential earthquake hazard for this region.