A nearly nine-mile-wide asteroid struck with Earth 66 million years ago, causing a global extinction that wiped out the majority of dinosaurs and three-quarters of the planet’s plant and animal species. Now we know that the so-called Chicxulub asteroid also caused a tremendous “megatsunami” with waves exceeding one mile in height.
Scientists were recently able to reconstruct the impact of the asteroid according to a study published in AGU Advances. Scientists were able to estimate the collision’s catastrophic consequences, which included a global tsunami that caused widespread flooding.
In addition to providing insight into the geology of the end of the Cretaceous period, the findings helped experts piece together facts regarding the extinction of the dinosaurs.
“This was a global tsunami,” said Molly Range, a scientist at the University of Michigan and the study’s corresponding researcher. “All of the world did see this.”
Following the asteroid’s impact, there would be extreme rises in water level in two phases, the team found: the rim wave and subsequent tsunami waves.
“If you just dropped a rock in a puddle, there’s that initial splash; that’s the rim wave,” Range said.
These rim waves could have reached an inconceivable height of one mile — and that’s before the tsunami really gets going, the paper estimates.
“Then you see a wedge effect with the water being pushed symmetrically away [from the impact site],” Range said, noting that the Chicxulub asteroid struck in the Gulf of Mexico just north of what’s presently the Yucatán Peninsula.
After the first 10 minutes post-impact, all of the airborne debris associated with the asteroid stopped falling into the Gulf and displacing water.
