Series of Strong Earthquakes Hit Italy

January 18, 2017

A series of strong earthquakes are hitting central Italy since 09:25 UTC on January 18, 2017. Within the first two hours, EMSC registered 21 moderate to strong earthquakes. This region is currently under powerful blizzard conditions with parts under more than 2.5 meters (8.2 feet) of snow.

The strongest earthquake so far was M5.7 at a shallow depth of 9 km (5.6 miles), according to the EMSC. USGS registered the same magnitude and a depth of 10 km (6.2 miles).

The epicenter was located 5.3 km (3.3 miles) NW of Amatrice and 30.7 km (19.1 miles) NNW of L’Aquila, and about 96 km (60 miles) NE of capital Roma, Italy.

There are about 3 015 234 people living within 100 km (62 miles).

The quakes are hitting the region devastated last year by a series of destructive earthquakes in which nearly 300 people lost their lives.

The M5.7 quake was strongly felt in capital Rome where the metro system and some schools have been evacuated.

There are no immediate reports of casualties or damage but this region is under powerful blizzard conditions and heavy snow which is blocking roads and limiting initial assessment.

Below is a list of all earthquakes registered by the EMSC between 09:25 and 11:07 UTC today.

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.

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