M6.0 Earthquake and aftershocks, Island of Crete, Greece

[Astronuc]

M 6.0 - 7 km NNW of Thrapsanón, Greece​

https://earthquake.usgs.gov/earthquakes/eventpage/us7000fes8/executive

• 2021-09-27 06:17:22 (UTC)
• 35.252°N 25.260°E
• 8.7 km depth

Seismotectonics of the Mediterranean Region and Vicinity​

The Mediterranean region is seismically active due to the northward convergence (4-10 mm/yr) of the African plate with respect to the Eurasian plate along a complex plate boundary. This convergence began approximately 50 Ma and was associated with the closure of the Tethys Sea. The modern day remnant of the Tethys Sea is the Mediterranean Sea. The highest rates of seismicity in the Mediterranean region are found along the Hellenic subduction zone of southern Greece, along the North Anatolian Fault Zone of western Turkey and the Calabrian subduction zone of southern Italy. Local high rates of convergence at the Hellenic subduction zone (35mm/yr) are associated with back-arc spreading throughout Greece and western Turkey above the subducting Mediterranean oceanic crust. Crustal normal faulting throughout this region is a manifestation of extensional tectonics associated with the back-arc spreading. The region of the Marmara Sea is a transition zone between this extensional regime, to the west, and the strike-slip regime of the North Anatolian Fault Zone, to the east. The North Anatolian Fault accommodates much of the right-lateral horizontal motion (23-24 mm/yr) between the Anatolian micro-plate and Eurasian plate as the Anatolian micro-plate is being pushed westward to further accommodate closure of the Mediterranean basin caused by the collision of the African and Arabian plates in southeastern Turkey. Subduction of the Mediterranean Sea floor beneath the Tyrrhenian Sea at the Calabrian subduction zone causes a significant zone of seismicity around Sicily and southern Italy. Active volcanoes are located above intermediate depth earthquakes in the Cyclades of the Aegean Sea and in southern Italy.

https://earthquake.usgs.gov/earthquakes/eventpage/us7000fes8/region-info

https://www.bbc.com/news/world-europe-58705376

At least one person has been killed and nine injured after a 5.8-magnitude earthquake hit the Greek island of Crete, local officials say.

The man died when the dome of a church that was being renovated in the town of Arkalochori caved in.

Aftershocks
4.8 5 km ENE of Pýrgos, Greece
2021-09-27 04:02:25 (UTC-07:00)10.0 km

4.4 4 km E of Kastélli, Greece
2021-09-27 01:21:58 (UTC-07:00)10.0 km

4.2 8 km W of Arkalochóri, Greece
2021-09-27 00:46:31 (UTC-07:00)10.0 km

4.5 1 km N of Kokkíni Cháni, Greece
2021-09-27 00:30:46 (UTC-07:00)10.0 km

4.6 Crete, Greece
2021-09-26 23:37:45 (UTC-07:00)7.4 km

 

[Greg Bernhardt]

Thank you for sharing the information about the recent earthquake near Thrapsanón, Greece. I can provide some additional insight into the seismotectonics of the Mediterranean region and how it relates to this earthquake.

The Mediterranean region is known for its high seismic activity due to the convergence of the African and Eurasian plates. This convergence has been ongoing for millions of years and has resulted in the closure of the Tethys Sea and the formation of the Mediterranean Sea. The highest rates of seismicity in this region are found along the Hellenic subduction zone in southern Greece, where the African plate is subducting beneath the Eurasian plate.

The earthquake near Thrapsanón occurred in a seismically active area known as the Hellenic Arc, which extends from the western coast of Turkey to the southern tip of Greece. This area is characterized by frequent earthquakes, as well as volcanic activity in places like the Cyclades and southern Italy. The M 6.0 earthquake that occurred at a depth of 8.7 km is likely related to the ongoing convergence and subduction of the African plate beneath the Eurasian plate.

Aftershocks are common after a significant earthquake, and the ones you mentioned in your post are typical for this type of event. These aftershocks can continue for days, weeks, or even months after the initial earthquake, but they generally decrease in magnitude over time.

I also want to express my condolences for the loss of life and injuries caused by this earthquake. It serves as a reminder of the importance of earthquake preparedness and building codes in seismically active regions.

Thank you for bringing attention to this event and the ongoing seismic activity in the Mediterranean region. As scientists, it is crucial to monitor and study these earthquakes to improve our understanding of the Earth's processes and potentially mitigate future impacts.