The massive 7.8 magnitude earthquake killed over 2300 people and injured thousands of others, with many people still trapped beneath the rubble of collapsed buildings.
Video / AP / @journoturk / Abier Khatib / Pankaj Kumar / Selin Marta
The devastating earthquakes that struck Turkey and neighbouring Syria with tragic force were centred on one of the world’s most seismically active — and politically turbulent — regions.
Strain accumulated over decades as Earth’s slow-moving tectonic plates pushed against one another was released in a few seconds, causingviolent vibrations as rock masses suddenly overcame friction and snapped past each other.
Such seismic stresses build up in the region of Turkey because the Arabian plate is pushing the Anatolian plate westward at a rate of about two centimetres per year, according to David Rothery, a professor of geosciences at the Open University in the UK.
Joanna Faure Walker, head of University College London’s Institute for Risk and Disaster Reduction, said: “Turkey has experienced the deadliest earthquake worldwide four times in the last 50 years — in 2020, 1999, 1983 and 1975.”
Monday’s first quake, which hit in the early hours with a magnitude of 7.8, originated at the southwestern end of the East Anatolian fault near its junction with the Dead Sea fault system. The quake was all the more devastating because it took place at a relatively shallow depth of 18 kilometres.
A baby is rescued from a destroyed building in Malatya, Turkey, February 6. Photo / DIA Images via AP
The second big quake, only slightly less powerful at magnitude 7.5, followed nine hours later about 100km north-east of the original tremor, at a depth of just 10km. There were also dozens of other smaller quakes, or aftershocks.
“The two events are almost certainly connected,” said Mark Allen, head of the earth science department at Durham University in the UK. “Releasing the stress on one fault zone can load up the stress on another, where it then dissipated in another quake.”
The East Anatolian fault zone, which was responsible for Monday’s events, has been relatively quiet over the past century but has caused several devastating earthquakes in the more distant past.
A historical parallel was an 1822 earthquake in the same area “which completely ruined many towns with heavy casualties”, said Roger Musson, research associate at the British Geological Survey. “In Aleppo alone about 7000 were said to have been killed ... The 1822 earthquake also had many aftershocks continuing into June the following year.”
Catherine Mottram, senior lecturer in structural geology and tectonics at the University of Portsmouth, said southern Turkey was “a very similar geological setting to the San Andreas Fault in North America”.
A man searches collapsed buildings in Diyarbakir, southern Turkey. Photo / Depo Photos via AP
The North Anatolian fault running east-west along Turkey’s Black Sea coast has been much more active in recent times than its East Anatolian counterpart, causing several catastrophes including the magnitude 7.6 Izmit earthquake in 1999 that killed about 18,000 people.
But the two faultlines were sufficiently far apart to make it unlikely that even severe quakes in one would trigger activity in the other, said Allen.
“Geophysicists will be able to reconstruct exactly where movement occurred along the fault by reconstructing data collected by seismometers in the region, so more information should come out in the coming days and weeks about exactly what happened,” added Mottram.
Social scientists will be examining the aftermath too. Although many countries rushed to offer co-operation and aid to Turkey and Syria in the immediate aftermath of the quakes, Ilan Kelman, professor of disasters and health at University College London was not optimistic.
His research on “disaster diplomacy” suggested that natural disasters did not create peace.
“Aside from the logistical challenges of humanitarian aid amid places of violence, experience demonstrates that, sadly, previous enmity tends to supersede saving lives and stopping war over the long term,” he said.
