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Scientists say they have unearthed details of how the dinosaurs were wiped out 65 million years ago. A team of geophysicists is analyzing rock formations in a crater under the seabed off Mexico. The rocks contain the remnants of the cataclysmic aftermath of a gigantic asteroid impacting with Earth. The scientists say the layers of rock they have extracted reveal a step-by-step account of the destruction that happened after the impact as rock and sediment settled on top of each other in revealing layers. Geophysicist Jay Melosh from Purdue University said: "It tells us what went on inside the crater on that day of doom that killed the dinosaurs. All of this mayhem is directly recorded in the core."
Scientists say the asteroid was around three to four kilometers wide. It smashed into the ocean and created a hole 160kms wide and 20kms deep. This triggered a chain reaction of earthquakes, tsunami, icecap melting, landslides and fires that forever changed the geology and life forms on Earth, killing off the dinosaurs. The asteroid's impact hurled out rock and minerals and created a massive crater. Molten rock fell back into the crater, which was then filled with ocean water from tidal waves. This water was full of soil, vegetation, animal life and other debris, all of which settled in layers ready for scientists to analyze millions of years later. The scientists say this layer-forming process took just a few hours.
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