Rock samples that were taken from the Chicxulub crater in Mexico is shedding more light on the impact of the force brought about by the large asteroid that caused the extinction of dinosaurs about 65 million years ago.
The Chicxulub Impact
The asteroid popularly attributed to the extinction of the prehistoric dinosaurs triggered earthquakes, wildfire, volcanic eruption and tsunamis.
Now, a new study published in the journal Science on Nov. 18, offers an idea on the force of the asteroid's impact.
Rapid Process
When the dinosaur-killing asteroid hit the Earth, the surface of the planet momentarily acted like a liquid. The extraterrestrial rock ripped a big hole as it buried itself into the Earth's crust causing materials lying deep in the abyss to hurtle upward.
The asteroid pushed the rocks beneath the surface farther downward and then outward triggering the formation of a mountain range twice taller than Mount Everest before collapsing downward and outward again eventually forming a peak ring.
Scientists said that these series of events happened within a very short period occurring in under 10 minutes.
"If this deep-rebound model is correct (it's called the dynamic collapse model), then our peak ring rocks should be the rocks that have travelled farthest in the impact - first, outwards by kilometres, then up in the air by over 10km, and back down and outwards by another, say, 10km," said University of Texas geophysicist Sean Gulick. "So their total travel path is something like 30km, and they do that in under 10 minutes."
Earth's Surface Acting Like A Liquid
Gulick likened the process to what happens when a rock is tossed into a pond except that the materials involved during the impact were solid.
"If you picture all of this happening in a slightly slower-moving fluid than water would be, you can envision that the center that rebounds upwards and splashes upwards would kind of collapse outwards," said Gulick, who is part of the team that drilled into Chicxulub's peak ring.
"So just as the sides are falling in, this rebounding center is sort of collapsing outwards to create ... this ring of mountains, made from material that ultimately came from fairly deep."
Study researcher Joanna Morgan, from the Imperial College London, said that the abrupt impact caused the rocks to lose their strength and cohesion dramatically reducing their friction. She said that this can help explain why the rocks behaved like fluid.
