How big was the earthquake between Turkey and Syria?
Monday a 7.8–earthquake measuring 7.5 on the Richter scale in Turkey and Syria resulted in more than 15,000 deaths and many more missing. Current estimates say that more than 400 buildings collapsed and at least 1,300 more damaged in Syria and at least 5,600 buildings destroyed in Turkey.
The Loma Prieta earthquake in California shook with such force that the San Francisco Bay Bridge partially collapsed on commuters. The 1989 earthquake killed 63 people and injured more than 3,700 residents. It was a magnitude 6.9 earthquake.
The difference in damage between these events is partly due to infrastructure, but also how we report seismic activity. Recording the magnitude gives scientists an idea of the scale of earthquakes, but the energy these events release makes them deadly. The size is logarithmic, meaning their differences are exponential. The magnitude 7.8 Turkey-Syria earthquake produced forces about 20 times stronger than the magnitude 6.9 Loma Prieta earthquake.
Earthquake magnitudes of this size are measured on the logarithmic scale: Moment Magnitude. This means that the distance from one integer to the next is a difference of a factor of 10. A 7.0 earthquake is ten times stronger than a 6.0 and a hundred times stronger than a 5.0.
The difference between the energy released in an earthquake is even greater. Digit by digit, the strength of an earthquake is 32 times greater than the previous one.
Dara Goldberg, a research geophysicist with the United States Geological Survey, says it’s especially important to think about this scale when you get larger-magnitude earthquakes: “The difference in energy between a magnitude 4.0 and a magnitude 4.1 pales in comparison to the difference between magnitudes 7.7 and 7.8… that magnitude value is critical to understanding what its impact might be.
This is the strength of all the earthquakes the world has experienced in the past year.
Put another way, the energy generated by the recent earthquakes between Turkey and Syria is greater than the sum of all California earthquakes in the past year. It is greater than the sum of all earthquakes in the past three months.
It’s important to remember that in the case of Turkey and Syria, says Golderberg, “already partially damaged sectors are particularly vulnerable, even to aftershocks of moderate magnitude.”
With aftershocks typically occurring weeks or months after the main quake, the Turkey-Syria region will brace itself during the lengthy rescue, recovery and reconstruction process.