Scientists Explore the Crater Left from the Asteroid That Killed the Dinosaurs
Less time separates us from Tyrannosaurus rex than separated them from the Stegosaurus. That something that might be hard to wrap your head around, but the age of the dinosaurs was a longer period that we humans often imagine.
But then a giant asteroid hit earth about 66 million years ago, and, well, eventually gave birth to the Texas oil industry. Not that long ago, researchers found a crater on the Yucatan peninsula in Mexico, and they believe it may be ground zero for the impact that helped do in the dinosaurs.
This month a team of researchers began drilling into this seminal crater. One of those scientists is Sean Gulick from the Institute of Geophysics at the University of Texas. He called the Standard from the drill site. He's on a 245-foot-long lift boat lifted up above the water, with a small mining rig stuck on the bow.
The team is planning to drill down 1,500 meters – a little less than a mile – into the Chicxulub crater’s subsurface.
Gulick says the team is clothed in their personal protective devices: hard hats and safety goggles.
The crater itself is buried beneath a kilometer of limestone on average. It’s officially half on-shore and half off-shore. Gulick says the team has images of the offshore part of the crater, so they know what they’re drilling into.
"What we're actually targeting is a ring of mountains near the center that is the closest to the sea floor, so it's only 650 meters down (a little less than half a mile),” Gulick says. “We think we can actually get into the crater at this site.”
The entire crater is 200 kilometers across, or about 124 miles in diameter. The team is drilling near the center, about 60 kilometers off. They will extract core samples about 10 feet long to analyze fossils and changes in rock type. They also might test DNA trapped in the samples.
"We're actually wanting to learn about the mass extinction event itself,” Gulick says.
The idea is to find out what caused 75 percent of life on earth to go extinct 66 million years ago. They’re looking for the types of life that reemerged at the crater, whether it was species who could only live in a narrow range of conditions or who were able to survive a wide variety of changes in the environment. They might also find organisms that were tolerant in the specific type of ocean chemistry available after the asteroid’s impact.
“Also we want to study the life that occupied the crater itself,” Gulick says. “We think extreme life, exotic life, basically moved into the hydrothermal system in the center of the impact.”
Gulick says the team doesn't know if they'll find new species or some similar to those that now live at mid-ocean ridges or in the ocean's hot environments - animals that live off of chemistry rather than sunlight.
"It's a fundamental question,” Gulick says. “It could be a place where life can get a foothold. So it might be a place to think about where life got started early on Earth."
Another fundamental question is understanding the energy release of the impact, Gulick says. Scientists have models about how and when the asteroid hit.
"It blows open a hole and collapses in, and things kind of rebound like throwing a rock in a pond, splashing outward,” Gulick says.“We hope to get some answer as to … what kind of material and how much material we might expect to be blown up into the atmosphere and into outer space to rain back in on us – to get a sense of the kind of kill mechanisms that might have happened 66 million years ago."
This post prepared for web by Beth Cortez-Neavel.
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