Asteroid impact ended the dinosaurs – Further confirmation
Recent research has almost confirmed that the dinosaurs were completely destroyed by the impact of an asteroid in Mexico nearly 66 million years ago.
This research has been published online in the journal Science.
The impact of the asteroid, nearly 15 kilometers (9 miles) wide resulted in the most recent and most familiar mass extinction, i.e. Cretaceous-Paleogene extinction that destroyed nearly 75% of the planet’s species including almost every dinosaur. Birds are considered as the only survivors among the dinosaurs.
The impact by the asteroid resulted in more than 110 miles (180 kilometers) wide gargantuan crater near Chicxulub, Mexico. The impact by the asteroid resulted in the release of huge amount of energy that was more than 100 trillion tons of TNT or more than a billion times than the atom bombs that destroyed Hiroshima and Nagasaki.
Previously, findings showed that the Chicxulub impact occurred either 300,000 years before or 180,000 years after the end-Cretaceous mass extinction but recent study, in which scientists utilize high-precision radiometric dating analysis of debris, showed that the two events happened no more than 33,000 years apart.
“We’ve shown the impact and the mass extinction coincided as much as one can possibly demonstrate with existing dating techniques,” Paul Renne, study co-author and director of the Berkeley Geochronology Center, told LiveScience.
However, according to Renne, Earth’s climate was also responsible along with the impact for the mass extinction.
“The impact was clearly the final straw that pushed Earth past the tipping point,” Renne said. “We have shown that these events are synchronous to within a gnat’s eyebrow, and therefore, the impact clearly played a major role in extinctions, but it probably wasn’t just the impact.”
“Low-diversity mammalian fauna in the western Williston Basin persisted for as little as 20,000 years after the impact. The Chicxulub impact likely triggered a state shift of ecosystems already under near-critical stress.” Researchers wrote.
Reference:
Renne, P., Deino, A., Hilgen, F., Kuiper, K., Mark, D., Mitchell, W., Morgan, L., Mundil, R., & Smit, J. (2013). Time Scales of Critical Events Around the Cretaceous-Paleogene Boundary Science, 339 (6120), 684-687 DOI: 10.1126/science.1230492
