Magnitude-7.2 Earthquake in Eastern Turkey

A USGS ShakeMap shows the intensity of shaking caused by the earthquake in eastern Turkey on October 23, 2011

A magnitude-7.2 earthquake struck 12 miles northeast of the city of Van in eastern Turkey on Sunday, October 23, 2011, at 1:41 p.m. local time at the epicenter (time in other time zones).

The earthquake occurred at a depth of 12.4 miles and caused strong shaking throughout a broad area, causing significant damage to Van and neighboring towns.

The current version of the USGS Prompt Assessment of Global Earthquakes for Response (PAGER) estimate is that economic losses are most likely to be in the $1–10 billion range, and fatalities are equally likely to be in the 100–1,000 or the 1,000–10,000 range.

Did You Feel It? Individuals report on the intensity of shaking

The earthquake struck in the eastern part of Turkey near the borders with Iran and Iraq. As of this writing, 325 people in 138 cities throughout Turkey, Iran, Iraq, Georgia, Syria, and the surrounding region had responded on the USGS Did You Feel It? website.

History of strong earthquakes

Turkey is a tectonically active country that experiences frequent destructive earthquakes. This earthquake is a reminder of the many deadly seismic events that Turkey has suffered in the recent past.

• In 1999, a devastating magnitude-7.6  earthquake near Izmit broke a section of the North Anatolian Fault (approximately 620 miles to the west of the October 23, 2011, earthquake), killing 17,000 people, injuring 50,000, and leaving 500,000 homeless.
• In 1976, a magnitude-7.3 earthquake struck near the border of Turkey and Iran (approximately 40 miles from the October 23, 2011, earthquake), destroying several villages and killing 3,000 to 5,000 people.
• In 1939, a magnitude-7.8 earthquake struck near Erzincan, killing an estimated 33,000 people.

Tectonics of this earthquake

On a broad scale, earthquakes in this region are controlled by the collision of the Arabian Plate and Eurasian tectonic plates. At the latitude of this event, the Arabian plate converges with Eurasia in a northerly direction at a rate of approximately 24 millimeters per year.

In the area of Lake Van and further east, tectonic activity is dominated by the Bitlis Suture Zone (in eastern Turkey) and Zagros fold and thrust belt (which extends toward Iran). This earthquake occurred beyond the eastern extent of Anatolian strike-slip faulting, which is similar to the San Andreas Fault in California. The focal mechanism of this earthquake is consistent with oblique-thrust faulting similar to mapped faults in the region.

For the most recent information on this earthquake, maps, and scientific and technical information, visit Magnitude 7.2 – Eastern Turkey.

Flash animation of a strike-slip fault

Flash animation of a thrust fault