A thin iridium layer marks the dinosaur extinction
A global layer of iridium in rocks provides compelling evidence of the asteroid impact 66 million years ago that caused the extinction of dinosaurs and 75% of Earth's species.
Sixty-six million years ago, an asteroid impact wiped out the dinosaurs. Evidence for this cataclysm is a global layer of iridium, a rare metal on Earth but common in space rocks. This thin band, found worldwide in ancient sediments, shows iridium levels up to 30 times higher than normal, proving a massive extraterrestrial object vaporized upon impact.
There's more to this story — open the app to keep reading.
Continue Reading in App
1 more paragraphs · plus a 2-question quiz