His discovery of coesite, which became a standard sign of an impact crater, sealed the debate.
He backed up Paul Toy, the Metro-Dade police diver who was called upon to probe the impact crater.
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They take samples from an ancient hydrothermal vent inside Haughton Crater, a large impact crater that dominates the landscape and attracts the most scientific attention.
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Now fast-forward to 2013, where in the past few weeks the Curiosity rover has been drilling into some different rocks half a planet away, inside a deep basin formed by the Gale impact crater.
The iridium, and the end of the dinosaurs, she believes, were caused by another impact whose crater has yet to be located.
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The moment most people were persuaded that the dinosaurs were killed by an impact was when the crater in Mexico was shown to have been created 65m years ago, at the end of the Cretaceous period.
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The impact that created the Malaren crater (which happened about a billion years ago) fragmented 250 cubic kilometres of rock.
No one disputes that these globules were formed from stuff melted and thrown into the air by the impact, because their chemical composition matches rock from the crater itself.
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The war will go on around him as he sits in the small crater left at the mortar's point of impact.
Most tellingly, she says that rock cores taken recently from the crater itself show a band of sediment above the impact that contains fossils of tiny creatures that became extinct only at the end of the Cretaceous.
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Further examination revealed a crater rich in shocked quartz and iridium, minerals that are commonly found at impact sites. (These are also the telltales in distant layers of ejecta that the rock in question has come from an impact.) Most important, the rocks above and below Shiva date it to 65m years ago.
The crater, three miles across, has the characteristic central mound of a fresh meteorite impact.
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Highlighting the risks such asteroids pose to the planet, researchers at the University of California, Berkeley, on Thursday tightened the link between the demise of most dinosaurs 66 million years ago and the impact of a six-mile-wide asteroid that left a 110-mile-wide crater off the Yucatan coast of Mexico.
As researchers studied images of the McLaughlin Crater, a crater 57-miles across and 1.4 miles deep that formed as the result of an impact with a large meteor, they noticed sedimentary rocks.
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