You thought you were having a bad day? Imagine that of the dinosaurs – and more generally of (almost) all living things on Earth – 66 million years ago, when a giant asteroid hit the planet in the worst possible place.
Because the hell the ball of rock we’re standing on lasted only a few hours before the sun returned: two new studies have identified what they believe is evidence of disasters as daunting as they are long.
We know some of the effects caused by the fall of this celestial body – precisely the type of deadly rock that NASA sought to destroy with its DART mission – in the Yucatán Peninsula, in Mexico, at the place marked by the famous crater by Chicxulub.
Earthquakes, tsunamis, volcanic eruptions, acidification of the oceans, a veil of dust blocking the sun and collapsing all the food chains: all this has led, scientists say, to the extinction of almost all non-avian dinosaurs, and to that of 93% of the mammals which until then prospered quietly.
Two studies, notably relayed by New Atlas, specify some of these events. The first is the work of scientists from the University of Michigan, who simulated the tsunamis caused by the thing, comparing their data to those, geological, from one hundred and twenty sites around the world.
They relied on previous data, indicating that a 14 kilometer wide asteroid would have hit the Earth at the crazy speed of 43,200 km / h. According to their models, in the first minutes following the impact, a wall of water 4.5 kilometers high would have formed, before falling heavily to the surface.
Ten minutes after the shock, a giant circle-shaped tsunami, a frightening height of 1.5 kilometers, was then said to have started its apocalyptic journey. It would have taken only twenty-four hours to sweep the entire surface of the globe, with a power that is difficult to imagine.
According to the scientists and the geological verifications of their simulations, the North Atlantic and the South Pacific were the hardest hit, when the disaster was somewhat less in the South Atlantic, the North Pacific, the Indian Ocean and the Mediterranean.
Watch out for bumps
The second study was conducted by Hermann Bermúdez of Montclair State University in New Jersey. Hermann Bermúdez investigated the geological consequences of the Cretaceous-Paleogene extinction, analyzing the composition of outcrops in Colombia, Gorgonilla Island, Mexico and the United States, Alabama, Texas and in Mississippi.
On the island of Gorgonilla, 3,000 kilometers from the crater of Chicxulub, the Colombian discovered disturbances in the sediments which he considers to be the result of earthquakes that occurred immediately after the impact.
He also discovered vitreous spherules, small balls of glass melted by the power of the impact, projected into the sky then falling to the ground, as well as tektites and micro-tektites.
As New Atlas explains, it took months for this layer of spherules to form. It is however marked by the same type of deformations as the upper layer of sediments – mud and sand – previously mentioned: according to Hermann Bermúdez, this would be proof that the earthquakes that followed the impact of the asteroid would not have ceased for weeks, if not months.
Terrifyingly long, the tremor would also have been unimaginably powerful. The researcher thus calculates that the planet, after the impact of the asteroid, would have been struck by an earthquake representing an energy of 1023 joules. This is 50,000 times more than the one that devastated the Indian Ocean in 2004. With a magnitude of 9.1 on the Richter scale, it caused more than 220,000 human victims.