![]() ![]() "But they are all well-populated now, and many are popular tourist destinations. "While this had a major impact on people in Chile, the South Pacific islands were uninhabited when they took a pummeling from the tsunami 3,800 years ago," Goff said. They think their research could better inform us of the potential dangers of future megathrust quakes. It was over 1,000 years before people returned to live at the coast again, which is an amazing length of time given that they relied on the sea for food."Īs this is the oldest known discovery in the Southern Hemisphere of an earthquake and tsunami devastating human lives, the researchers are excited to probe the region further. "Our archaeological work found that a huge social upheaval followed as communities moved inland beyond the reach of tsunamis. "The local population there were left with nothing," Goff said. ![]() These stone walls, built by humans, were found lying beneath the tsunami's deposits, and some were lying backward, pointing toward the sea, suggesting that they had been toppled by the strong currents of the tsunami's backwash. 10 of the deadliest natural disasters in historyįurther evidence also came in the form of ancient stone structures that the archaeologists excavated. Swarm of more than 55 earthquakes strikes off Oregon coast Deepest earthquake ever detected should have been impossible The half-life of carbon 14, or the time it takes for half of it to radioactively decay, is 5,730 years, making it ideal for scientists who want to peer back into the last 50,000 years of history by checking how much undecayed carbon 14 a material has.Īfter dating 17 deposits across seven separate dig sites over 370 miles (600 km) of Chile's northern coast, the researchers found that the ages of the out-of-place coastal material suggested that it had been washed inland some 3,800 years ago. ![]() As carbon 14 is everywhere on Earth, deposits easily absorb it while they form. This method involves measuring the quantities of carbon 14, a radioactive carbon isotope, found inside a material to determine its age. To get a better sense of what brought these deposits so far from the sea, the researchers used radiocarbon dating. "And we found all these very high up and a long way inland, so it could not have been a storm that put them there." "We found evidence of marine sediments and a lot of beasties that would have been living quietly in the sea before being thrown inland," Goff said in the statement. Eventually, so much strain gathers that the point of contact between the plates rips apart, creating a gigantic rupture and releasing energy in the form of devastating seismic waves.Įvidence for the giant quake was found in marine and coastal items - such as littoral deposits (boulders, pebbles and sand native to coastal regions) and marine rocks, shells and sea life - that the researchers discovered displaced far inland in Chile's Atacama Desert. The two plates eventually get locked into place by friction, but the forces that caused the plates to collide continue to build. These earthquakes occur when one of Earth's tectonic plates gets forced, or subducted, underneath another. ![]() Like the Valdivia earthquake, the ancient quake was a megathrust earthquake, the most powerful type of earthquake in the world. ![]()
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