Diamonds not a dinosaur's best friend.As the last remaining dinosaurs neared their end, a dusting of microscopic diamonds apparently fell from the sky, according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. a scenario proposed by two Canadian researchers who found extremely tiny diamonds in 65-million-year-old rocks from Alberta. That time corresponds to the mass extinctions mass extinction, the extinction of a large percentage of the earth's species, opening ecological niches for other species to fill. There have been at least ten such events. that wiped out the last dinosaurs as well as many other animal and plant species at the end of the Cretaceous period Cretaceous period (krĭtā`shəs), third and last period of the Mesozoic era of geologic time (see Geologic Timescale, table), lasting from approximately 144 to 65 million years ago. . David B. Carlisle of Environment Canada Environment Canada (EC), legally incorporated as the Department of the Environment under the Department of the Environment Act ( R.S., 1985, c. E-10 ), is the department of the Government of Canada with responsibility for coordinating environmental policies and in Ottawa and Dennis R. Braman of the Royal Tyrrell Museum of Palaeontology The Royal Tyrrell Museum is located in Midland Provincial Park 6 kilometres from Drumheller, Alberta, Canada. It is 135 kilometres from Calgary. It is known the world over as an outstanding palaeontology museum and research facility. in Drummheller, Alberta, isolated micrograins of carbon having diamond-like properties from the Alberta rocks. Each diamond measures 3 to 5 nanometers across, they report in the Aug. 22 NATURE. The diamonds are so small that "1,000 of them strung end to end would make a necklace for a bacterium, if bacteria had necks," says Carlisle. He and Braman believe the microdiamonds may have some connection with the mass death at the end of the Cretaceous. Over the last decade, scientists have accumulated evidence that a meteorite meteorite, meteor that survives the intense heat of atmospheric friction and reaches the earth's surface. Because of the destructive effects of this friction, only the very largest meteors become meteorites. or comet struck Earth at that time and caused the extinctions. The Canadian researchers suggest the diamond dust was either brought to Earth by the impacting meteorite or created during the high-pressure collission. The impact would have lofted the diamond dust and other rocky debris high into the atmosphere, blocking out sunlight and causing a wide range of environmental problems. With time, the diamonds then fell to Earth, the researchers suggest. |
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