Scientists say they are now able to describe in detail how the asteroid that killed the dinosaurs produced its huge crater – the singular event that changed the course of Earth’s history.
The reconstruction was made possible by drilling into the Chicxulub Crater – the remnant of the crater made 66 million years ago – and examining the rocks present, the BBC reports. The analysis showed that the asteroid hit the planet so hard that the surface sloshed back and forth, like what happens when a glass of water is rocked.
At one point in this upheaval, a mountain higher than Mt. Everest shot up before crumbling back down into a smaller mountain range, the scientists say. Professor Joanna Morgan from Imperial College London says,
And this all happens on the scale of minutes, which is quite amazing.
This study confirms a model on dynamic crater formation, and will greatly help explain the resulting changes on the Earth’s geology.
When the 15-kilometer asteroid crashed, it made a hole 100 kilometers wide and 30 kilometers deep. The central area gradually created an inner “peak ring.” It is covered by limestone deposits, but can be seen in an arc of sinkholes known as cenotes.
The scientists spent May to June of this year drilling a core through the crater, which is located under the sediments in the ocean off the Yucatan Peninsula in Mexico. They theorized that the “peak ring” of the crater should contain rocks that moved the farthest during the impact, dense granites from 10 kilometers down.
They found what they were looking for. Professor Sean Gulick from the University of Texas says, “Once we got through the impact melt on top, we recovered pink granite. It was so obvious to the eye – like what you would expect to see in a kitchen countertop.”
The granites were deformed and fractured, showing evidence of having been under enormous pressures. An analysis of the core materials extracted formed a picture of what happened, how the crater started to collapse on itself and the center briefly heaved upwards to form peaks.
The results of the study can now also provide a template for scientists to further understand the surfaces of other planets.
The drilling project was conducted by the European Consortium for Ocean Research Drilling (ECORD) as a part of the International Ocean Discovery Program (IODP), with the support of the International Continental Scientific Drilling Program (ICDP). The discovery was published in Science magazine.