It is a tectonic twofer.
While earthquakes are known to destroy things once and for all, they have never been documented to return for a second aid to destruction – so far.
In a new seismic study published in Nature Geoscience, an international team of geologists has uncovered evidence of a “boomerang earthquake” – a type of earthquake that can be recycled – which shook the seabed under the Atlantic Ocean in 2016.
“Our new study provides some of the clearest evidence for this enigmatic mechanism occurring with a real fault,” said Stephen Hicks, an earthquake seismologist at Imperial College London.
Underwater seismometers detected tectonic terror traversing the Romanche Fracture Zone, a 560-mile-long fault located roughly halfway between Brazil and Africa, reports National Geographic. The team then analyzed the epicenter position of the earthquake and the energy released by each noisy phase to join the parts.
They found that as ordinary drummers focused their energy in one direction, the 7.1-size monster – called a “supershare breakdown that spreads to the back” – reportedly tore to the east before doubling back and forth. in the opposite direction at an accelerated speed.
“This was a kind of weird configuration to look at,” Hicks said of the ground-breaking event.
Even more terrifying, the quake traveled at an earthquake rate of 11,000 mph on the return trip – so fast that it generated the geological equivalent of a sonic boom. Or, to put it simply, as fast as living from London to New York in 18 minutes.
Unfortunately, researchers are not entirely sure what caused the boomerang quake. “Although the structure of the fault seems simple, the way the earthquake grew was not, and it was completely the opposite of how we expected the earthquake to look,” Hicks said.
However, it is an exciting discovery considering that the seismic phenomenon, so far, has been observed mainly in theoretical models. “To the best of my knowledge, this is the first time it has been reported,” geophysicist Yoshihiro Kaneko of GNS Science in New Zealand told National Geographic.
Most importantly, the groundbreaking findings could help researchers understand how “boomerang earthquakes” could potentially affect inhabited areas, according to Kasey Aderield, a seismologist with the Research Institutions Involved in Seismology.
This is not the first geological phenomenon that scientists tremble in their boots. Seismologists have warned that last year’s tremors in Southern California have increased the chance of a major San Andreas Fault earthquake.