happyworld - Experts Drilled Into The Crater That Killed the Dinosaurs And Made An Incredible Discovery

Scientists know what happened here – the Chicxulub crater marks the point of contact for an asteroid so enormous that it wiped out a planet’s worth of dinosaurs. But as they dig into the massive divot, they realize precisely what happened when the space rock struck the earth. And their findings paint a terrifying picture, to say the least.
Of course, much was already known about the Chicxulub crater. It stretches 93 miles in diameter and plunges a stunning 12 miles into the ground. Of all the known impact points on Earth, it’s the second-largest in the world. And even though it appeared about 66 million years ago, its peak ring remains in one piece.
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This particular detail highlights just how stunning the Chicxulub crater – and its long-term preservation – has already proven to be. It’s the only crater on the planet that has its peak ring still intact. The next available one for scientists to study sits, rather inconveniently, on the moon.
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Still, all of this information has to do with the crater’s dimensions and exterior features. Now, though, scientists have gone beyond the topical details of the Chicxulub crater. Digging into the expanse, which sits a kilometer beneath Mexico’s Yucután Peninsula, they uncovered the impact that an up to 50-mile-wide asteroid had on the planet.
The Chicxulub crater derives its name from the nearby Mexican town of the same name. And experts estimate that an asteroid or comet, ranging in size from 6.8 to 50.3 miles in diameter, smashed into the earth at this very spot.
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It’s hard to imagine such a massive piece of space debris hurtling in the direction of our planet. Perhaps even more stunning is the abyss it left behind; the Chicxulub crater has an estimated diameter of 93 miles. For reference, that’s just 1.6 miles shorter than the drive between New York City and Philadelphia.
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Image: Hohum
Image: Hohum
Experts have been able to calculate the strength with which the space rock smashed into the earth, too. They estimate that it had 21 to 921 billion times as much energy as the atomic bomb dropped on Hiroshima in World War II. Even the Soviet Union’s Tsar Bomba – the strongest human-made explosive to ever detonate – couldn’t compare. The asteroid or comet released 100 million times the energy of Tsar Bomba upon impact.
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Image: Júlio Reis
Image: Júlio Reis
So with that much power, the size of the Chicxulub crater makes sense. It’s not just its width that’s extra-large, either – the crater reaches depths of up to 18.6 miles into the earth. These dimensions make Chicxulub the second-largest impact crater on earth, just behind Vredefort in South Africa.
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But Chicxulub has one feature that no other known crater on earth has; as we mentioned earlier, it’s a peak ring crater. This means that the impact site has no single central peak. Instead, the crater has a circle-shaped plateau encompassing its center. The rim of the crater encircles this ring, but it sits at a distance from the center.
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Marine geophysicist Sean P.S. Gulick explained to The New York Times in 2016 just how rare the peak ring feature was. He said, “Chicxulub is the only crater on Earth with an intact peak ring that we can go sample… It’s ground zero of the Cretaceous extinction event.”
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And yet, scientists haven’t necessarily rushed to dig into the Chicxulub crater. That was partly due to the fact that massive hole appeared approximately 66 million years ago. Over time, rock and water filled in the void; and eventually, about a kilometer of sedimentary rock covered the crater.
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Also, scientists didn’t discover the Chicxulub crater until relatively recently, especially considering it has been around for millions of years. The first to stumble upon it were geophysicists Glen Penfield and Antonio Camargo, who found the crater in 1978. And they weren’t looking for the asteroid impact site when they discovered it – they were searching for petroleum.
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Image: USGS
Image: USGS
So, Penfield and Camargo took to the skies to complete a magnetic survey that mapped any potential drilling locations beneath the Gulf of Mexico. As he pored over the resulting data, though, Penfield noted something particularly extraordinary; a 40-mile-wide “underwater arc” with impeccable symmetry.
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Such a strange discovery inspired Penfield to dig deeper. He sought out a gravity map commissioned by his employer, oil company Petróleos Mexicanos, in the 1960s. On it, he noticed another arc, but this one curved over the Yucatán Peninsula itself. When he put that map and his magnetic survey together, he realized the two arcs made a circle.
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Penfield knew he had found something spectacular; the geophysicist hypothesized that he had pinpointed a cataclysmic event in the planet’s geological history. Petróleos Mexicanos allowed him and Camargo to present their findings at the 1981 Society of Exploration Geophysicists conference. Unlike the asteroid they presumed to have hit the earth, though, their presentation made little impact at the time.
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Image: FrankRamspott
Image: FrankRamspott
Eventually, Penfield gave up on his research into the crater – much of the evidence he sought had been destroyed or lost. Nevertheless, he published all of the data he had and returned to work. Meanwhile, though, other scientists had begun to theorize something similar, without having seen Penfield’s research.
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Image: via Innovation.ca
Image: via Innovation.ca
Specifically, a graduate student at the University of Arizona, Alan R. Hildebrand, and his adviser, William V. Boynton, had published their own Earth-impact theory in 1981. They just needed to find a crater that could corroborate their hypothesis. The pair had plenty of geological evidence, too, and their work got a bit more traction than Penfield’s.
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Image: Jlanghurst
Image: Jlanghurst
Namely, a professor in Haiti named Florentine Morás uncovered evidence that an ancient volcano had once stood in his country. Hildebrand consequently realized that such a feature could have emerged when a major force of impact crashed nearby. And in 1990 he learned the precise spot of such a collision.
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Image: Dementia
Image: Dementia
In that year, Carlos Byars, who reported for the Houston Chronicle, clued Hildebrand into Penfield’s findings. The journalist mentioned that the geophysicist had thought he had found an impact crater in the vicinity. So, Hildebrand picked up the phone and the two started analyzing drill samples from the oil company’s storage unit.
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Image: DatGuy
Image: DatGuy
What Penfield and Hildebrand found amid the drilling debris were shock-metamorphic materials. Such substances appear after an impact-related event causes deformation and heating. In normal cases, shock-metamorphism occurs along with a volcanic eruption, but, of course, Penfield and Hildebrand had uncovered something much bigger than that.
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Since then, more research into the Chicxulub crater has transpired, and more theories about its origins have arisen. For instance, in September 2007 authors William F. Bottke, David Vokrouhlicky and David Nsvorny offered a theory to Nature magazine. They said that the rock responsible for creating the crater came from a specific cosmic family called the Baptistina asteroids.
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In spite of facts that seemed to corroborate Vokrouhlicky, Bottke and Nesvorny’s theory, new evidence released in 2011 negated their claim. Researchers had pinpointed the Baptistina asteroid family’s formation to around 80 million years ago. This would make it nearly impossible for the space rock to reach earth when the Chicxulub crater formed 66 million years ago. That’s because it takes multiple tens of millions of years for asteroids to collide and resonate.
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The discovery of the Chicxulub crater also lent credibility to a theory first formed by physicist Luis Alvarez and his son, Walter Alvarez, a geologist. Both men believed that between the Cretaceous and Paleogene periods, a massive impact on earth had triggered a series of animal and plant extinctions. And among them were all of the non-avian species of dinosaurs.
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Image: NASA Universe
Image: NASA Universe
Apparently, some of the Chicxulub crater’s statistics do fall in line with the Alvarez theory. For one thing, initial dating of the crater estimated its formation happening about 66 million years ago. This timing would have the asteroid or comet slamming into earth just between the Cretaceous and Paleogene periods, just as the father-and-son duo suspected.
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As such, many people believe the Alvarez theory about the Chicxulub crater – the impact that caused it also triggered a mass extinction of, among other species, land- and sea-dwelling dinosaurs. Still, though, so much mystery surrounded the enormous undersea divot. So scientists would have to drill into it to learn more.
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It then came time for such an excursion in 2016. Marine geophysicist Gulick and geophysicist Joanna Morgan helmed a crew of over 30 who represented a dozen different countries. The researchers boarded a boat and sailed into the Gulf of Mexico; and there, they transformed their vessel into a drilling station.
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The drilling station stood tall on three legs, rising about 40 feet above the Gulf of Mexico’s turquoise waters. From there, the team drilled incredibly far into the Earth. After the tool delved 60 feet underwater, it met the rock below and continued to dig a stunning 2,000 feet into the crust.
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Of course, over a 66-million-year period, the Chicxulub crater had filled with a sizeable amount of limestone and sediment. But the scientists worked their way past the new collection of rock to find what they were looking for; the material that made up the planet’s only peak ring crater.
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Gulick, Morgan and their team discovered that a peculiar type of rock made up the peak ring – granite. Normally, this variety of rock is found far deeper in the Earth’s crust than it appears in the crater. This meant that the asteroid had such an incredible impact that it pushed sediment from miles beneath the surface all the way to the top.
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Image: UT Jackson School of Geosciences via KUT
Image: UT Jackson School of Geosciences via KUT
Geophysicist Morgan, who worked for Imperial College London, told The New York Times, “These rocks behaved like a fluid for a short period of time, and rocks don’t tend to do that. It’s a very dramatic process when you form a large crater.” Apparently, such a chain reaction gave credence to something called the dynamic collapse model theory.
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The dynamic collapse model theory hypothesizes that the asteroid’s impact pushed rocks deep into the Earth’s crust before pushing them back up and out of it. Then, these rocks collapsed back down and settled to form the crater’s peak rings. And the fact that granite forms the crater’s central plateau goes hand-in-hand with such a theory.
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But drilling into the Chicxulub crater revealed more than one truth about this devastating geological event. The rocks also told the story of what happened once the asteroid smashed into the Earth, which scientists revealed in 2019. And the picture they painted of the world post-impact was a terrifying one, to say the least.
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Gulick said he and the rest of the scientists could be so specific with their findings because they had an unprecedented amount of rock to work with. He explained to The New York Times, “We normally get to read rock records that give us centimeters per thousand years. We have 130 meters for a day.”
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The rocks told a story that went like this – first, an enormous chunk of cosmic rock slammed into the ground, instantly creating a crater 60 miles wide and 20 miles into the Earth. The initial impact created waves in the nearby gulf, quite literally. A tsunami formed, charging in the opposite direction of the new crater.
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The asteroid’s impact also sent huge pieces of rock hurtling into the air, as far as the planet’s upper atmosphere – and likely beyond even that. Gulick theorized that “almost certainly some of the material would have reached the Moon.” The largest bits, meanwhile, flew up before crashing back down on the ground, still hot from the initial impact.
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Image: Mp
Image: Mp
Some smaller pieces of hot rock took longer to fall – and had more time to cool. These geological wonders, called tektites, scattered across the North American continent. Then, water started rushing back into the crater after it waved outward. But refilling the geological depression would be tame compared to the next stage.
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Image: shannonstent
Image: shannonstent
When the asteroid collided with the Earth, it sent a tsunami speeding off in the opposite direction. Of course, water ebbs and flows; so, soon enough, those powerful waves returned back toward the crater. Multiple massive tsunamis with waves towering hundreds of feet in the air then came back over the gaping geological hole.
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The rush of back-and-forth tsunamis quickly filled the peak ring with a four-inch coating of sand and gravel. And as the Gulf raged, so, too, did the land close by. Furthermore, the asteroid’s impact had also sparked wildfires across the area. Scientists knew this because they pinpointed pieces of charcoal in the peak ring just above the tsunami sediments.
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These wildfires could have started from the asteroid’s scorching thermal energy upon impact. The aforementioned shower of molten rock could have had something to do with it, too. Either way, Gulick told The New York Times, “Probably not everything burned, but certainly there were global wildfires.” Altogether, the tsunamis, falling rock and fires wiped out a stunning number of Cretaceous-era species, too.
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It’s hard to believe that scientists could conjure such haunting images from layers of rock hidden deep beneath the Yucatán Peninsula. For planetary geologist Paul Byrne, the Chicxulub crater’s layers made palpable some long-standing scientific theories. He told the newspaper that it was one thing to develop and simulate such hypotheses, but it was “quite another to see it.” And, considering the size and scope of the crater, this could be just the beginning of the startling secrets uncovered there.

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