The United States Geological Survey recorded a Magnitude 5.1 Earthquake at a depth of 6 km, about 31 km to the east of the island of Alonnisos in the Sporades Archipelago of the western Aegean Sea slightly before 1.50 am local time on Thursday 12 October 2017 (slightly before 1.50 pm on Wednesday 11 October GMT). No damage or injuries have been reported following this event, but people have reported feeling the event from much of western Greece.
The approximate location of the 12 October 2017 Rhodes Earthquake. USGS
The Aegean Sea is underlain by the Aegean Sea Plate, a small tectonic plate caught between the African Plate to the south, the Anatolian Plate to the east and the Eurasian Plate to the northwest. The Anatolian Plate is being pushed to the west by the northward movement of the Arabian Plate to the east, pushing the Aegean Plate south and west into collision with the northward moving African Plate. Part of the African Plate is being subducted beneath the Aegean Plate along the Hellenic Trench, which runs to the south of the Greek Islands from Cyprus to Crete then northwest under the Ionian sea parallel to the Peloponnesian Coast. This is not a smooth process, as the plates frequently stick together then break apart once the pressure has built up sufficiently, leading to (fairly frequent) Earthquakes.
Simplified map of the plate movements of the eastern Mediterranean. Univeriteit Utrecht.
Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.
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