Making their way to the seafloor near Mexico, scientists extracted a unique geological record of the single worst day in Earth's history when a city-sized asteroid crashed the planet 65 million years ago, wiping out dinosaurs and three-quarters of it another life.
Their analysis of these new rock samples from the Chicxulub Crater, released publicly on Monday, revealed a parfait of debris accumulated on layers almost minute by minute at the base of the impact during the first day of global catastrophe. It records traces of explosive melting, massive earthquakes, tsunamis, landslides and forest fires as the huge asteroid drilled a hole 1
The sludge also offers chemical evidence that the cataclysm has blown hundreds of billions of tons of sulfur from ocean spray into the global winter, causing global temperatures to drop as much as 30 degrees Fahrenheit for decades, scientists say.
"That tells us what happened inside the crater that day of the death that killed the dinosaurs," says Jay Melosh, a geophysicist at Purdue University who studies impact craters and is not a member of the drilling team. this is directly written to the nucleus. "
Scientists at the drilling consortium led by geophysicist Sean Gulick of the University of Texas at Austin, who co-authored the $ 10 million project, published their research in the Proceedings of the National Academy of Sciences. is sponsored by the International Program
Scientists worked aboard a drilling vessel called Lifeboat Myrtle, anchored off the coast of the Mexican port of Progresso, in 2016, for the first time, they drilled into the inner edge of the crater. buried in the seafloor below about 1,500 feet of limestone deposited millions of years after the impact.
Geologists study the rocks as a record of time of compaction, with ticks of a geological clock, usually measured in layers that accumulate over thousands of years. However, hundreds of feet of sediment accumulate rapidly in the Chicxulub Crater, recording impactful effects such as a high-speed stop camera,
"We have 130 meters in one day here," said Dr. Gulik. "We can read it on the scale of minutes and hours, which is incredible."
The asteroid exploded a cavity between 25 and 30 miles deep in the first seconds of impact, creating a bubbling cauldron of molten rocks and super heated steam, according to scientists. about the rock. Bouncing from the hammer blow, a jet of molten rock spilled over a peak higher than Mount Everest.
In minutes he collapsed into himself, scattering giant waves of lava outward, which hardened into a ring with high peaks, say scientists
About 20 minutes or more later, seawater curved back to the newly formed peaks. covering them in a blanket of shock rocks, scientists say. Over the course of minutes, waves are strangled with volcanic glass and a split rock that breaks back and forth, covering the peaks in a layer of rock called suevite, scientists said. Over time, the backwash of waves added more and more finely graded debris.
Scientists have discovered traces of organic matter and charcoal at the very top of the rock core. "We think the tsunami reflected brought back these traces of earth and these small, small fragments of charcoal," said Dr. Gulick. "The Earth is Clearly Burned."
Earth is usually moved by the cosmic rain of debris. In 2013, a relatively small meteor about 30 meters in diameter and weighing about 13,000 metric tons exploded in the air over Russia, damaging about 7,200 buildings and injuring about 1,400 people.
GET THE FOX NEWS APPLICATION  Inspired by the discovery of the Chicxulub Crater in the 1970s, astronomers and NASA routinely map the orbits of nearby asteroids and meteorite swarms. The space agency is planning a mission in 2021 to a nearby asteroid called Didymos to test ways to safely deflect a dangerous comet or asteroid before it hits.
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