An outstanding fossil deposit was found in North Dakota that looks like an extraordinary record of the mass extinction event that abolished most of the dinosaurs 66 million years ago. It seems that the fossils are animals that were killed in minutes from an asteroid striking Earth.
Paleontologists and researches are expressing cautious enthusiasm and have stated they have never seen anything like it.
A swathe of species was wiped out 66 million years ago. Opposing to popular belief, it didn’t demolish the dinosaurs: birds are still around, and they are a kind of dinosaur. Even though, non-avian dinosaurs didn’t survive. Evolution of primates and ultimately humans is owed to this extinction as it allowed mammals to flourish.
The Chicxulub crater was the main cause – an impact crater buried underneath the Yucatán Peninsula in Mexico. It was formed by a large asteroid about 10-80 kilometers wide.
The immediate blast was devastating, and a widely accepted theory is that worldwide climate disruption from the event was the cause of the mass extinction. The explosion also led to years of cold weather as sunlight was blocked because so much dust was thrown up into the air. The huge volcanic eruptions in what is now India may have also contributed to the extinction.
It is believed that powerful vibrations from the asteroid impact were sent causing widespread floods and earthquakes. The fossil deposit at the center of the controversy conserves the site of a river, which would have experienced a flash flood as water dashed inland. It is a mixture of sand and mud containing a compactly packed collection of fossilized fish and other organisms. Everything appears to have been laid down in a single flood.
In theory, it’s possible that this site has no link to the Chicxulub impact as floods happen all the time. But the team of researchers have numerous lines of evidence relating to the asteroid impact. The residues are thick with tektites: gravel-sized bodies composed of brown, black, green or gray natural glass formed from terrestrial debris ejected during meteorite impacts. The Chicxulub meteorite match the tektites match on a chemical level. Several of the fish have tektites in their gills, signifying the tektites were floating in the water. Lastly, the deposit is topped by a distinctive rock layer that is acknowledged to mark the extinction event.
