Turkey-Syria quake: The Anatolian Plate is one of the most seismically active; here is why

The Anatolian Plate sits between three major tectonic plates: African, Arabian and Eurasian
Photo: @kiraincongress / Twitter
Photo: @kiraincongress / Twitter

This story has been updated

An earthquake of magnitude 7.8 struck Turkiye, one of the most seismically active regions in the Mediterranean and the world, in the wee hours of February 6, 2023. The epicentre was Pazarcik near Gaziantep, a city near the country’s border with northern Syria.

This was followed by 25 aftershocks, with six having magnitudes of 5 and larger, according to the United States Geological Survey (USGS).

The death toll currently in Turkiye and Syria is over 3,000, according to media reports. A second earthquake of magnitude 7.5 shook southeast Turkey centred in Elbistan later on February 6, according to media reports.

Why Anatolia?

Turkiye (the Turkish/Anatolian plate) sits between three major tectonic plates: African, Arabian and Eurasian. Collisions between the Arabian and African plates with Eurasia typically result in earthquakes, according to a 2021 review paper.

The Anatolian plate is divided into three major fault zones:

  • North Anatolian Fault Zone (NAFZ)
  • East Anatolian Fault Zone (EAFZ)
  • South Eastern Anatolian Thrust Zone (SAT)

The North Anatolian Fault is similar to the San Andreas fault of California. The February 6 earthquake and the aftershocks occurred along or in the vicinity of the EAFZ, the USGS wrote on its website.

Earthquakes occur along faults, which are fractures between blocks of rock, allowing them to move relative to one another.

In some places along the East Anatolian Fault, the Anatolian Plate slid past the Arabian plate with a slip of up to three metres, MyRadar Weather, a weather application website, tweeted.

Further, most destructive earthquakes have struck NAF in the past. “It hosted seven magnitude 7-7.8 earthquakes in the past century. The EAF had nothing larger than magnitude 6.8 until today,” Edwin Nissen, professor at the University of Victoria, wrote on Twitter.

Since 1970, only three earthquakes of magnitude 6 or larger have occurred within 250 kilometres of the February 6 earthquake.

Nissen, however, added that historical records paint a different picture. EAF witnessed many large earthquakes during the last two centuries. They occurred in 1866, 1874, 1893 and 1971, the 2021 study noted.

The 1114 AD earthquake destroyed the city of Marash, Turkey. “So, it shouldn’t come as a total surprise,” Nissen added.

Further, there is only lesser than a 6 per cent chance of a bigger quake following the 7.8 event, according to MyRadar Weather.

So far, some 15 million people have experienced “strong,” “very strong” or “severe” shaking as measured on the Modified Mercalli Intensity scale, Matthew Cappucci, Meteorologist at MyRadarWX, wrote on Twitter.

The Modified Mercalli Intensity Scale describes the effects of an earthquake on human beings, natural structures and industrial installations in a given region.

The scale is designated in roman numerals. According to the USGS, the earthquake’s intensity was XI, which means violent.

“The epicentre is near the Syrian border where there is quite a high population density. Even before we get more information, you know this isn’t going to be good,” Stephen Hicks, a seismologist at the University College London, wrote on Twitter.

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