Now, scientists plan to drill 5,000 feet (1,500 meters) below the surface of the Chicxulub crater in Mexico to bring up a giant core — and delve 10 million to 15 million years into the past. The endeavor would result in the first offshore core taken from near the center of the crater, which is named for a nearby seaside village located on the Yucatán Peninsula.
An international team of scientists met last week in Mérida, Mexico, located within the 125-mile-wide (200 kilometers) Chicxulub crater, to discuss their plans for the drilling project, slated to start in spring 2016.
Why now? “The Chicxulub impact crater has been a remarkable scientific opportunity for the 20 years since it’s been discovered,” said Sean Gulick, of The University of Texas at Austin Institute for Geophysics.
And, for the first time, scientists have subsurface images from the offshore part of the crater, so they can pinpoint a spot for sampling. They chose a spot along the crater’s peak ring — a ring of mountainlike structures around the center of the crater.
By sampling there, the researchers can get a clearer picture of ancient biological and geological processes.
Scientists think that, when a big rock smashes into Earth at high enough velocities, the collision causes the crust temporarily to act sort of like a liquid, first forming a so-called transient crater (like the indentation that forms on a lake surface after a rock is thrown in), and the center rebounds, or splashes, upward and then outward.
“We think the peak ring is the record of the material that rebounded and splashed outward,” Gulick told Live Science.
All of these ideas are based on models and aren’t necessarily what happened. “We’ve never gotten a rock back from a peak ring to know if that’s correct,” Gulick said.
Read more at Discovery News
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