Doctor of Science Enrique Diego Arango Arias, is one of the specialists who work at the National Center for Seismological Research (Cenais) of the Republic of Cuba and is head of the National Seismological Service

More than 36,000 people have been killed and tens of thousands injured after the earthquake that struck Syria and Turkey on February 6.

Scenes of pain have gone around the world and the danger posed by earthquakes once again turns on the alarms about these phenomena.

What caused the earthquake in Turkey?

Was it related to the telluric movement that occurred a few days ago in Cuba?

What are the most prone areas to suffer these phenomena in our country?

Is there a risk of tsunamis for the Greater Antilles?

To talk about these and other topics,

Cubadebate

invited Dr. Enrique Diego Arango Arias, head of the National Seismological Service, to its weekly podcast.

Play the debate.

Listen to the Podcast:

Next, we publish a summary of the main ideas presented by the doctor.

To hear the full interview, listen to our podcast.

A very intense earthquake recently occurred in Turkey and the alarms about telluric events return.

Why do earthquakes occur?

Earthquakes occur due to the sudden release of energy where there is a large accumulated deformation in the blocks cut by an active fault.

There comes a time when the rocks cannot withstand the pressure to which they are subjected and the earthquake of tectonic origin occurs.

There are other earthquakes caused by the processes of magma movement in active volcanoes, by underground landslides, earthquakes induced by oil extraction through fracking (hydraulic fracturing) and by filling of large reservoirs, among others.

In the case of the most recent event that has claimed the lives of more than 30,000 people, what were the geological conditions for it to occur?

In the image you can see the north fault and the east fault of Anatolia.

In the east, which joins Turkey and Syria, was where the earthquake on February 6 was recorded.

Graphic: France24.

Turkey is located in a very complex region from a tectonic point of view.

In its territory there are two active faults, the North Anatolian fault and the Eastern Anatolian fault, which constitute limits of 4 tectonic plates, the Anatolian plates, the Eurasian plate, the Arabian plate and the African plate.

As a consequence of this phenomenon, how much did the surface of the land move?

Four shocking photos of horizontal displacements due to the earthquake in Türkiye.

The East Anatolian fault experienced a rupture of about 400 km, shifting by up to 4 meters in part of that rupture.

Is there any relationship between this earthquake that mainly affected Turkey and Syria with the earthquake registered on February 8, 600 km southwest of the Isle of Youth?

There is no direct relationship, both earthquakes occurred in plate boundary areas that have no tectonic link.

Sometimes a strong earthquake triggers earthquakes, mainly in areas near the epicenter that are about to cause an earthquake.

This may have been the cause of the origin of the second 7.5 earthquake that occurred after a 7.8 earthquake on a nearby fault zone.

It is important to comment that the waves generated by a strong earthquake completely shake the terrestrial globe, vibrate like a bell and are recorded by all broadband seismological stations in the world for several hours.

What have been the largest earthquakes recorded in Cuba and its surroundings?

The largest magnitude earthquakes recorded in Cuba are: the one that occurred on May 25, 1992 with a magnitude of 6.9 that was felt in the eastern half of the country with a maximum intensity of VII degrees, the one that occurred on January 28, 2020 in the vicinity of the Cayman Islands that was felt throughout the country.

The seismological history of Cuba records the occurrence of more than 20 strong earthquakes, among which are those of June 1766 and August 1852 south of Santiago de Cuba that caused damage with IX degrees intensities in this city.

The last strong earthquake that occurred in Cuba that caused damage to 80% of the city of Santiago de Cuba was recorded on February 3, 1932.

Which are the most seismic zones of the country and which faults or fault system are associated?

The most important seismic zones of the country are found in the eastern region related to the Oriente fault, which constitutes a limit between the North American plate, to which Cuba belongs, and the Gonave micro plate, located to the south;

and to the continuation of the fault of the north of Hispaniola, located to the north of the eastern tip of Cuba.

Other seismic fault zones that generate earthquakes in Cuban territory, known as plate interiors, are the Pinar fault (located in the west of the country) and the fault zone located in the northern part of the national territory, from the north of the province of Villa Clara to the northern zone of Camagüey-Tunas.

Another of the phenomena that condition earthquakes are Tsunamis. Can Cuba be affected by these?

What areas of the country could be the most affected?

The coasts of Cuba do not have a high danger before the impact of tsunamis.

The closest area where tsunamis have originated and which is capable of generating an earthquake with the potential to generate a tsunami is located to the north of the island of Hispaniola, where the fault mechanism is favorable for the occurrence of tsunamigenic tsunamis.

A tsunami that occurred in this area could affect to some extent localities located to the north of the eastern end of Cuba.

These days, a meeting was held to reduce risks in the face of the impact of natural disasters, among which are earthquakes, how Cuba prepares for these phenomena.

The event was rather to coordinate the support of the United Nations associations present in Cuba in the event of a strong earthquake that significantly affects the city of Santiago de Cuba.

In this sense, coordination is established with the direction of the National Civil Defense, where the OACEs and their territorial counterparts from other provinces participate to direct the necessary aid to the affected territory, with the logistical support of the United Nations associations present in Cuba.

see also

Cuba in Data: Seismic activity, how 2021 passed and what can happen (+ Chronology and PDF)