A new study has found that the East Anatolia Fault, site of the deadly February 2023 earthquake, formed 5 million years ago thanks to the pressure of the Eurasian and Arabian plates.
The creation of the rift ruptured the Earth’s crust extending from the North Anatolian Rift to the Dead Sea Rift, causing the Anatolian Plate to separate from the Eurasian Plate – marking the rebirth of the Dead Sea Rift. Tectonic plates.
Eastern Anatolia Fault It caused a deadly earthquake with a magnitude of 7.8 on February 6, which was followed hours later by a magnitude 7.6 on a different fault branching off the main East Anatolian Fault. More than 59,000 people died. While it is impossible to predict earthquakesA deeper understanding of the fault may help researchers understand which parts of the fault system are vulnerable to fracturing in the future and why, the study’s first author said. Donna Whitneyan earth scientist at the University of Minnesota.
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For example, the study showed that part of the Arabian plate is stuck under the Anatolian plate. The edge of this stuck piece of crust is located near the fault that erupted to cause the second earthquake near the Syrian-Turkish border. The force differential in the Earth’s crust caused by that extra layer may have been one of the reasons the quake started there, Whitney told Live Science.
“We had no idea there was going to be a big earthquake, not at all,” she said. “But it makes sense geologically.”
Whitney led a multidisciplinary team of earth scientists to investigate how the Anatolian plate formed. Researchers have used a variety of methods to study the area, including seismic surveys, which use seismic waves or induced vibrations to image what’s beneath the surface, and mineralogical dating to figure out the age of the rocks.
Because the rift allows hot fluids from the mantle to rise to the surface, it can heat minerals that researchers use to determine the age of rocks, essentially resetting their molecular clocks. Using these strange-looking minerals, the research team was able to determine when and where the East Anatolia Fault ruptured.
“We think that about 5 million years ago, everything was connected,” Whitney said.
The formation of the plate is due to the collision of the Eurasian and Arabian plates, which are slowly pushing towards each other. Add some extension, or sprawl, from the bottom of the Aegean Sea to the west, and “Anatolia had to move westward,” Whitney said. She said it was a bit like a watermelon seed slipping between two fingers, if the Eurasian and Arabian plates were the fingers, and the Anatolian plate was the seed. The researchers published their findings in the journal geology.
Since the formation of the plate, seismic activity has been concentrated around the North Anatolia Fault and the East Anatolia Fault. The East Anatolia Fault frequently causes moderate-sized earthquakes, and the largest in modern history before 2023 was a magnitude 6.8 that occurred in 2020, according to a paper in the journal Journal of the Geological Society. In 1939, an earthquake centered on the North Anatolia Fault Zone killed more than 32,000 people, according to the Geological Society, and a 7.6-magnitude earthquake in 1999 killed more than 17,000 people.
