3.5 billion-year-old glass beads found in Australia point to mega asteroid hit
Discovery makes it the second oldest known to have hit Earth and larger than the one blamed for wiping out dinosaurs
Australian scientists have found evidence of a huge asteroid they say slammed into Earth some 3.46 billion years ago – making it the second oldest known to have hit the planet and larger than the one blamed for wiping out the dinosaurs.
Andrew Glikson, from the Australian National University’s Planetary Institute, said that while the asteroid would have been massive, the exact location of where it hit was not known.
“The impact would have triggered earthquakes orders of magnitude greater than terrestrial earthquakes, it would have caused huge tsunamis and would have made cliffs crumble,” he said in a statement.
“Material from the impact would have spread worldwide.”
On Wednesday, Glikson said he and Arthur Hickman from the Geological Survey of Western Australia had found tiny glass beads called spherules, which are formed by vaporised material from an asteroid’s impact, in Australia’s remote northwest.
They were discovered in a sediment layer originally on the ocean floor and which had been preserved between two volcanic layers. It dates from 3.46 billion years ago.