EuroAsian Tectonic Fault Plates Collide

 

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Mapping the 100+ aftershocks from the Turkey-Syria earthquake

AJLabs

3 minutes

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Turkey has been hit by more than 100 magnitude-4+ quakes since a deadly 7.8 earthquake struck the southeastern region along the border with Syria on February 6.

More than 9,600 people have been killed with tens of thousands injured across Turkey and Syria after a magnitude-7.8 earthquake and powerful aftershocks struck.

The first earthquake hit at 4:17am (01:17 GMT) and was centred in Turkey’s Pazarcik district of Kahramanmaras province. Less than 12 hours later, a second 7.6-magnitude tremor rocked the same region.

(Al Jazeera)

100+ powerful aftershocks

Since February 6, Turkey has been hit by more than 100 aftershocks of magnitude 4 and greater. Aftershocks are smaller earthquakes that occur in the same general area following a major earthquake.

According to the United States Geological Survey (USGS), these seismic movements are minor readjustments along the portion of a fault that slipped at the time of the main quake. The frequency of these aftershocks decreases with time.

The strength of an earthquake is measured on the Richter scale and recorded on a seismograph. Magnitudes are based on a logarithmic scale, meaning for each whole-number increase on the scale, the magnitude is increased by a factor of 10.

(Al Jazeera)

While a magnitude 4 aftershock is generally considered light, it does result in noticeable shaking and may cause minor damage such as cracks on a wall. A magnitude-5 quake, by definition, is 10 times more intense than a magnitude-4 and can cause moderate damage to buildings.

A magnitude-6 earthquake is considered strong and is 100 times stronger than a magnitude-4 one. This type of earthquake can cause a lot of damage, particularly in heavily populated areas.

Since February 6, at least 81 magnitude-4 quakes, 20 magnitude-5 quakes, three magnitude-6 quakes, and two magnitude-7 quakes have been recorded in southeast Turkey.

The animated map below shows a time-lapse of all these quakes:

Strongest quake in Turkey since 1999

Turkey is in one of the world’s most active earthquake zones. Monday’s 7.8-magnitude earthquake is the most powerful to hit the country since 1999.

In August 1999, a powerful magnitude-7.6 earthquake shook Marmara, a densely populated region to the south of Istanbul, Turkey’s largest city, for 45 seconds. Within days, the official death toll stood at 17,500.

Here is a quick round-up of Turkey’s worst quakes during the past 25 years: