http://www.digitaljournal.com/tech-and-science/science/op-ed-the-day-the-asteroid-hit-the-dinosaurs-revealed/article/546751

Op-Ed: The day the asteroid hit the dinosaurs, revealed

Posted Apr 2, 2019 by Paul Wallis
The asteroid which ended the Cretaceous left dead fish with molten materials in their gills. Inland sea tsunamis. There was massive destruction 3200km from the impact site. It’s a grim picture, all together in one place, in Hell Creek, USA, North Dakota
Tyrannosaurus rex. Non-avian dinosaurs died out in the Cretaceous–Paleogene extinction event at th...
Tyrannosaurus rex. Non-avian dinosaurs died out in the Cretaceous–Paleogene extinction event at the end of the Cretaceous period. (An example of pruning the tree of life).
David.Monniaux (CC BY-SA 3.0)
The dig (called Tanis by paleo experts) is conducted by a team led by Robert DePalma, a doctoral student at the University of Kansas. Another team notable is Dr Walter Alvarez, son of Luis Alvarez, who together first formed the theory of an asteroid wiping out the dinosaurs.
The new find of a virtual snapshot of dinosaurs the day the asteroid hit is pretty staggering. The colossal shock from the asteroid strike smashed huge animals, trees, and marine animals. The big deposit of sea creatures was created as tsunamis swept inland.
Information available so far indicates:
• A big accumulation of dead animals and materials after impact. There was ecology-wide destruction, land, sea and air. The initial dig on the site started in 2013, and it’s taken until now for a complete picture to be created. That’s partly because of the sheer volume of materials to be dug, analysed, and evaluated. Materials dispersed include molten rock falling from the sky, melted amber, ant nests, wasp nests, a Triceratops, mammals, and a vast array of organic materials of all kinds.
• Massive heat caused by the impact transferred in to the atmosphere. There is a lot of evidence of fire, some caused by superheated glass rain.
• Evidence of magnitude 10 or 11 earthquakes. That’s total destruction on the Richter Scale.
• At least two gigantic tsunamis caused by events thousands of kilometres away. The first wave was a “standing wave”, caused by an earthquake. A secondary wave struck after the first, leaving materials deposited which later fossilized.
• The extraordinary mix of fossils from different environments. This bizarre mix of animals, trees, and fish means a single sudden catastrophic global event of incredible size and power.
• Atmospheric impacts and marine chemistry effects. It’s possible, but not yet proven, that the asteroid strike initially killed like a bomb, by removing all breathable air, and shock shock transfer through water. it may also have caused chemical poisoning of the water and wider environment after impact. This information is crucial to a better understanding of the exact nature of the extinction event.
An equivalent impact today would have effectively wiped out North America, in a matter of about an hour or so. The asteroid deposited a huge quantity of iridium, a rare element on Earth, but common in asteroids. The iridium layer, known as the KT boundary, is a deposit of dark materials, spread around the world. This boundary is also the generally accepted cutoff point for the end of the Cretaceous period.
This dig will generate a lot of geological, as well as paleo, information. The dynamics of such a big asteroid strike are yet to be fully explored. For example, the fact that an asteroid impact in Mexico’s Yucatan Peninsula caused tidal waves in Montana wasn’t an instantly obvious fact. The vaporization of rock and its spread around the impact zone was a reasonable supposition, but now, here it is, ready to be researched.
The research is due to be published soon. Some scientists are a bit skeptical of the claim that this find is a true picture of the asteroid impact event, but that’s also just standard practice – Examine the evidence first, before commenting. Whatever the story turns out to be, this was obviously a major event, and perhaps the best possible indicator of the risks of asteroid impacts.