Two major earthquakes struck Turkey’s southeastern region near the border with Syria on Monday, killing thousands and toppling homes in the region.
The first earthquake measuring 7.8 on the Richter scale occurred at 4:17am (01:17 GMT) in Pazarcik district of Kahramanmaras province in Turkey. Less than 12 hours later, a second 7.6 magnitude earthquake occurred in the same area. These earthquakes were felt by millions of people across the region up to 1,000 km. Earthquakes with a magnitude of 7 are considered major.
Since then, Turkey has been hit by more than 100 earthquakes of magnitude 4 or higher. Aftershocks are small earthquakes that occur in the same area after a large earthquake.
What areas were affected?
On Tuesday, Turkish President Recep Tayyip Erdogan declared a three-month state of emergency in 10 provinces in southeastern Turkey. These provinces are: Kahramanmaras, Adana, Adiyaman, Osmaniye, Hatay, Kilis, Malatya, Sanliurfa, Diyarbakir and Gaziantep.
On the Syrian side, the areas affected by the earthquakes are divided between government-controlled areas and the last pockets of the opposition, surrounded by Russian government forces.
Before and after satellite images give an idea of the extent of destruction in towns and cities across the region. Swipe right below to see how all the houses in Islahiye, Turkey, have fallen. [Handout: Maxar Technology via Reuters]
How do earthquakes happen?
The Earth’s surface, or crust, is made up of large blocks of rock called tectonic plates. These plates move continuously along the cracks where they meet, called fault lines. When the plates grind together they can stick together, which makes it difficult. Eventually, the stress becomes so great that they break, causing sudden movements that release energy as seismic waves. This vibration causes the ground to vibrate.
When an earthquake occurs underground it is called a focus; the area above it on Earth is the epicenter. There are several factors that cause an earthquake to be devastating, including the depth of the earthquake.
At a depth of 18 kilometers (11 miles) below the Earth’s surface, the 7.8-magnitude earthquake was very shallow – the proximity of seismic waves to the surface creates a strong tremor.
How are earthquakes measured?
Earthquakes measuring 7.8 and 7.6 are considered “major” on the Richter scale – which measures the strength of an earthquake.
Growth is based on a logarithmic scale, which means that the total number of the scale, growth, in this case, increases tenfold.
To put it in context, earthquakes register a 4th magnitude or less on the Richter scale is considered mild, but it can still cause damage.
A size 5 An earthquake, by definition, is 10 times stronger than a magnitude 4 and can destroy buildings.
Power 6 Earthquakes are generally considered strong and are 100 times stronger than a magnitude 4 earthquake.
Power 7 earthquakes are considered large, which can cause significant loss of life and damage to buildings.
The terrifying moments captured on camera give a glimpse of the extent of the destruction and horrors caused by the powerful earthquakes. The video below taken by a TV crew in Malatya shows the moment when the second magnitude 7 earthquake occurred.
TV crews were broadcasting when a second 7.5 magnitude earthquake hit Turkey ⤵️ pic.twitter.com/XM5VVH7Qrl
– Al Jazeera English (@AJEnglish) February 6, 2023
Seismic registration a size 8, 9 or more can cause great loss of life and total destruction of the affected area.
Size, depth, proximity to human settlements, soil conditions, and the potential for secondary disasters such as tsunamis and landslides are among the many factors that determine the extent of an earthquake’s damage.
Strongest earthquake in Turkey since 1999
Turkey is one of the most earthquake-prone regions. Monday’s magnitude 7.8 earthquake was the strongest to hit the country since 1999.
In August 1999, a 7.6-magnitude earthquake shook the Marmara region, which is south of Istanbul, with a large population, for 45 seconds. In just a few days, the death toll was 17,500.
Here is a quick breakdown of Turkey’s worst earthquakes over the past 25 years: