On Friday, 30 October, a magnitude 7.0 earthquake struck the sea near the Turkey and Greece borders at a shallow depth. The earthquake struck some 120 miles south of the western-most section of the North Anatolian fault, the seismic source that drives the majority of risk in Turkey.
The moment tensor indicates that this was a normal faulting type event with a north-south oriented extension; this is common in the Aegean sea and surrounding region. This is a large event for a normal faulting mechanism, making it likely this was the main shock event. Events with this faulting mechanism are less likely to trigger large aftershock activity than other faulting types.
While the epicenter was in Greece, the wider population affected would certainly impact both Greece and Turkey. We are expecting the event to have a higher impact in Turkey. Reports are sparse, but there are 20 reported fully collapsed buildings in Turkey, and local tsunami flooding has occurred. The figure above shows the modified Mercalli intensity (MMI) felt from the event; we would not expect to see any damage below MMI V (Moderate). As we can see, the potential area of damage covers the majority of Samos Island in Greece as well as large parts of the wider Izmir region.