By Volkan Sevilgen, Temblor
Two mid-size earthquakes, 120 km away and 1 hour apart, shook western Turkey causing widespread anxiety. Some 60 km away from the closest shock, In Izmir, the country’s third largest city, many people ran outside. Although construction quality has improved over the years, many people are unsure about the strength of their buildings. People who feel an earthquake should drop, cover and hold on to protect themselves from falling objects, as the majority of the earthquake injuries are caused by falling objects and not from collapsed buildings. In general, people are advised not enter damaged buildings until authorities check their safety.
Earthquakes are common in this part of the world as many of the natural beauties of the Turkish riviera such as valleys and coves are brought by the faults. Paired up with a great climate, this terrain made Turkey the 6th most visited country in the world.
Could have the earthquake near Usak triggered the quake near Manisa?
Quakes in close distance and time can influence each other’s occurrence. Some 120 km away from a magnitude 5 earthquake, the static stress changes (based on the deformation from the fault slip) would be too small to trigger an event. However, dynamic stresses (seismic waves) can travel much farther, so the second earthquake near Manisa might be triggered. Also, the groundwater especially geothermal water abundant in this region lubricates faults, which makes these faults more susceptible to dynamic triggering.
What would be the largest earthquake in our lifetime in this region?
Temblor calculates that the largest earthquake magnitude to be around 6.5 for this region in our lifetime. The Global Earthquake Rate Model uses globally recorded earthquakes in the past 30 years and ground deformation rates to determine the earthquake rate.
These earthquake should remind all of us that while we enjoy the beauties come from earthquakes, we should also build to withstand their shaking.