This is the map of Earth's tectonic plates

Since Monday, the death toll from the disaster has increased to 21,000 in Turkey and neighbouring Syria, according to CNN.

The cause of the Turkish-Sari earthquake, and all other earthquakes, lies in the phenomenon of plaque tectonics, that is, the continental shift of plaques that make up earth's mantle.

As the chart shows, some such tablets meet in Turkey, which significantly increases the risk of severe earthquakes.

More importantly, some plaques in Turkey are moving convergence, so they are approaching one another, which also makes major earthquakes more likely than in places where the plates leave.

More specifically, this week's East Anadol break, along which the earthquake took place, is marked by a convergous border with the African plate in the south and a transformational border of horizontal movement with the Eurasian plaque in the north.

Turkey lies on the Anadol Plaka, which is on the line of tension between the Arab and Eurasian Plaka.

The African tablet, which contributed to the formation of the Alps 60 million years ago by moving north, is also limited to the Anadol stela.

Throughout the Pacific Plaque lies the so - called Fire Ring responsible for much of the world's volcanic activity, another place where the limits of convergence plates exist.

The other plates are Australian plaques, North America and South America.

The strongest earthquakes in recent history took place all along the Fire Ring, which also includes the renowned Hendek Mariana, around Pacific Placa.