'Minute Difference' In Deadly Asteroid's Trajectory Could Have Saved Dinosaurs


The impact of an asteroid about 6 miles (10 kilometers) wide about 66 million years ago created a crater more than 110 miles (180 km) across near what is now the town of Chicxulub (CHEEK-sheh-loob) in Mexico's Yucatán Peninsula. Now again the question arises, regardless of which way went the evolution if dinosaurs managed to survive, and other, more recent types late in development.

The pair believe the key ingredient in the extinction was the soot, which was produced when the impact ignited rocks loaded with hydrocarbon molecules such as oil. This would involve an asteroid impact sending 385 million tons (350 million metric tons) of soot into the stratosphere. And this happens because the catastrophic chain of events could only have occurred if the asteroid had hit the hydrocarbon-rich areas occupying about 13 per cent of Earth's surface.

Talking about soot, it is a strong, light-absorbing aerosol that caused global climate changes.

A team of researchers led by Kunio Kaiho from Tohoku University in Japan, came to this conclusion by calculating the amount of soot in the stratosphere and estimating climate changes caused by it using a global climate model. They calculated that such oily rocks would have generated vast amounts of soot.

Researchers analysed the amount of sedimentary organic matter in the Earth to obtain readings of temperature anomaly caused by soot in the stratosphere.

If the asteroid had hit a low-medium hydrocarbon area on Earth - occupying about 87 per cent of planet's surface - mass extinction could not have occurred and the Mesozoic biota could have persisted beyond the Cretaceous/Paleogene boundary.

The scientists found that a mass extinction would have occurred from the impact only if it had hit 13 percent of the surface of the Earth, including both land and oceans.

According to the study, soot from hydrocarbon-rich areas caused global cooling of 8-11 degree Celsius and cooling on land of 13-17 degree Celsius.

At the time, these hydrocarbon-rich areas were marine coastal margins, where the productivity of marine algae was generally high and sedimentary rocks were thickly deposited.



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