Early Monday morning, an immense tragedy shook the world. A magnitude 7.8 earthquake ripped through Turkey and Syria, followed nine hours later by a 7.5 aftershock. The death toll stands at over 3,800, and rescuers have only just begun to comb through the collapsed buildings.
This blog post will explore the science behind such a devastating event and explain the complexity of the Earth’s crust that can lead to aftershocks that can last for months or even years. It will also discuss the likelihood of an aftershock bigger than the original quake.
Earthquakes are products of plate tectonics, and the magnitude 7.8 mainshock Monday morning struck along some 125 miles of the East Anatolian Fault, a well-known fault line in southern Turkey. This was a “strike-slip” earthquake, meaning stress built up between two masses of rock moving horizontally until the fault ruptured. It was also very shallow underground, meaning it created more intense shaking at the surface.
Aftershocks will continue to shake the area as local faults adjust to such a huge initial tremor, and scientists say that process could continue for not just days, but months or even years. There’s even a chance—albeit a small one—of an aftershock bigger than the original quake.
Generally speaking, the larger the mainshock, the larger the aftershocks, which tend to decrease in frequency and severity as time goes on. As you can see in this map, aftershocks of various intensities have been swarming along the original quake’s fault line, as well as at a different but connected fault line to the north, where the magnitude 7.5 aftershock seems to have hit.
That complexity means that what happens in one fault doesn’t stay there. It may have been that the stress that led to the 7.5 quake had been building for some time, and the jolt from the mainshock unleashed it.
This blog post will explore the science behind the tragedy that has shaken Turkey and Syria, and discuss the likelihood of aftershocks that could last for months or even years. We will also look at the complexity of the Earth’s crust and how it can lead to such devastating events. Read on to find out more about the science behind earthquakes and aftershocks.
Source: www.wired.com