It was yet another event triggered by the impact of a huge asteroid. We finally know all about the giant tsunami that killed the dinosaurs.
Waves up to a mile high, crashing onto the U.S. coast, penetrating up to several miles inland, are a literally apocalyptic scenario - one that actually led to the extinction, some 66 million years ago, not just of dinosaurs, but of 75 percent of the species living on planet Earth at the time.
The catastrophe should however be contextualized: yes, because a tsunami of this size is an event - fortunately - unique in its kind. Behind there is the impact on Earth of the meteorite that formed the crater of Chicxulub, in Yucatan, Mexico, 200 kilometers wide and still visible today.
What we know about the extinction of the dinosaurs
There is a general scientific consensus on the crash of the meteorite - whose width measured about 10 kilometers - as the cause of the extinction of the monstrous reptiles that dominated the Blue Planet before man. What, on the basis of this acquired fact, we are instead trying to refine, are the subsequent developments of the death of many living species caused by that one gigantic event.
For example, the tons of dust raised in the atmosphere by the fall of the asteroid caused a cooling of temperatures. And even the tsunami, whose traces are still preserved in the ground, as in a still image of millions of years, speak to us of the devastating consequences of Chicxulub.
Scientists have developed computer models of the waves, other one and a half kilometers, which poured over North Dakota, in the current United States, covering the distance of 3 thousand kilometers, from the Mexican meteoric crater. The traces of the tsunami are some fossils of marine animals, which should not be at such a great distance from the coast.
What is the colossal tsunami that devastated America and the dinosaurs
Other details come from a study published in Earth & Planetary Science Letters, whose evidence comes from an analysis carried out about a thousand kilometers north of the place of impact. We are in Louisiana: here, the seismic images of the underground layers show traces of water currents probably occurred during a tsunami. In particular, the attention of the researchers was focused on a field of "megaripples", very ancient marine rocks, too large at high altitude to have formed spontaneously. Considering also the orientation of the ripples carved in the rock, the hypothesis of the umpteenth event triggered by the violent landing of the celestial body on the ground, is very plausible.
The causes of the extinction of the dinosaurs are continually the subject of study and investigation: many hypotheses made recently, from the one that overturns the theory of the asteroid to the crater in Ukraine, which may have had a role in the disappearance of the ancient rulers of the Earth.
Giuseppe Giordano