M6.1 - EASTERN TURKEY

Tectonic Summary

Turkey is a tectonically active country that experiences frequent destructive earthquakes. At a large scale, the tectonics of the region near the recent earthquake are controlled by the collision of the Arabian Plate and the Eurasian Plate. At a more detailed level, the tectonics become quite complicated. A large piece of continental crust almost the size of Turkey, called the Anatolian block, is being squeezed to the west. The block is bounded to the north by the North Anatolian Fault and to the southeast by the East Anatolian fault. The March 8, 2010, earthquake occurred near the East Anatolian fault at its eastern end. The pattern of seismic-wave radiation from the source is consistent with left-lateral strike-slip displacement on a northeast-striking strike-slip fault, such as would be expected if the East Anatolian fault were the causative fault. The same radiation pattern, however, might also be associated with right-lateral strike-slip displacement on a northwest-striking strike-slip fault, which could occur in the same tectonic environment. Confident identification of the causative fault will await more detailed studies.

This earthquake is a reminder of the many deadly earthquakes that Turkey has suffered in the recent past. The devastating Kocaeli (Izmit) earthquake of 1999 (M = 7.6) broke a section of the North Anatolian Fault 900 km to the west of the recent quake and killed 17,000 people, injured 50,000, and left 500,000 homeless. The recent earthquake (March 8, 2010) occurred about 90 km south of the M = 6.6 earthquake of March 13, 1992, which killed hundreds of people and left thousands homeless in Erzincan. Another even larger earthquake struck Erzincan in 1939. This magnitude 8.0 earthquake killed an estimated 33,000 people.

Earthquake Information for Europe

Earthquake Information for Turkey