A geological fault in Turkish cities caused the new tremors

You Two large earthquakes with a magnitude of 6.4 and 5.8 struck the Defne and Samandag districts of Hatay, Turkey, on Monday (20)., due to a geological fault, experts say. It was opened on the roof of Antakya, the capital of that province, after The first earthquake on February 6th. The site is located in the south of Karamamaras province, the epicenter of the main earthquake, which had a magnitude of 7.8.

According to Professor Hasan Suzbilir, Director of the Center for Earthquake Research and Applications at Dokuz Eylul University, the fault in Antakya was ruptured due to the stress build-up caused by the initial event.

He said in an interview with the local press that preliminary information showed that the Antakya fault is the seismic source of the earthquakes on Monday in Hatay.

The Italian National Institute of Geophysics and Volcanology (INGV) confirmed that previous earthquakes created a new geological fault in the Anatolian Peninsula. This crack, measuring between 70 and 80 metres, moved soil about 10 meters towards the Aegean Sea.

Sözbilir visited the site a week ago for a technical evaluation. “The big earthquake caused a crack in Antakya, which could not bear the pressure. There was pressure build-up on the southern and northern ends of the fault. In the observations we made, we identified cracks that show that the fault was forced,” he said.

“The fault is located along the Gülbaşı-Türkoğlu line. A large part of the houses located along and near this area were destroyed,” said the researcher, who took measurements and recorded photographs of the highway’s leftward shift, along the fault. .

The cracks stretch for miles between Karamamaras and Hatay. Roads connecting and surrounding the area were destroyed. The Antakya-Demirkoberu Highway is full of potholes, some of which are quite large.

What is a geological fault?

A geological fault is a break in the surface (the earth’s crust), where two tectonic plates pass each other, and they can have different thicknesses, depending on the distance between two solid masses of moving rock.

Plate tectonics make up the planet’s solid outermost layer, the Earth’s crust. They support oceans and continents, and are subject to motion generated by heat from the glowing magma on Earth.

Turkey and Syria lie between three tectonic plates: the Eurasian, the Anatolian, and the Arabian.

See below a post with aerial photographs of a surface crack in the area extending for about 300 km:

The displacement of the plates produces energy, but the friction between them weakens this motion. Therefore, traction energy accumulates over centuries in parts of the earth’s crust, at points called faults. When friction and stress generate fractures and very intense movements in a short time, an earthquake occurs, the main shock.

If, as a result of strong shocks, there is disturbance in other “fragile” parts of the Earth’s surface in the same area, it is known as an aftershock. Therefore, faults are directly related to the occurrence of earthquakes.

Geologist Nasi Gurur, a member of the Turkish Academy of Sciences, explained that the Karamamaras seismic event enhanced energy transfer. “When an earthquake occurs somewhere, generally, part of the energy released travels to the south and the other to the north of that fault, towards the two ends.” Experts said this is what happened in southern Turkey on Monday.

Alerts

After two earthquakes in Karamamaras, Güror warned of the possibility of an earthquake in the Hatay region. That week, he said, “I think there may be a transfer of tension in the fault sites, because there is a burden. Those who live there have to be very careful.”

Days later, on Monday, in another interview, he revealed new predictions. “We said that faults here can break and cause an earthquake. We warned several days ago, and the earthquake that was expected occurred in Hatay tonight. My warning was based on a scientific prediction. There is still a risk of an earthquake of similar magnitude in Adana and Cyprus.”

Gürur said other sensitive areas are the Adana Basin, Mugla Province and sites near the Malatya fault, where there may have been some energy transfer.