A Canadian scientist claims that the element mercury, release from enormous coal fires, possible started by volcanoes, lead to one of the earth's great extinction events, at the the Permian-Triassic boundary.
The Permian–Triassic (P–Tr) extinction event, informally known as the Great Dying, was an extinction event that occurred 252.28 Ma (million years) ago, forming the boundary between the Permian and Triassic geologic periods, as well as the Paleozoic and Mesozoic eras. It was the Earth's most severe extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct. It is the only known mass extinction of insects.Some 57% of all families and 83% of all genera were killed. Because so much biodiversity was lost, the recovery of life on Earth took significantly longer than after other extinction events. This event has been described as the "mother of all mass extinctions."
Scientists have discovered a a new culprit likely involved in Earth’s greatest extinction event 250 million years ago (when rapid climate change wiped out nearly all marine species and a majority of those on land): an influx of mercury into the ecosystem.I'm skeptical, but it should be good for business...
“This was a time of the greatest volcanic activity in Earth’s history and we know today that the largest source of mercury comes from volcanic eruptions,” says Dr. Steve Grasby, a research scientist at Natural Resources Canada and an adjunct professor at the University of Calgary.
“We estimate that the mercury released then could have been up to 30 times greater than today’s volcanic activity, making the event truly catastrophic.”
Dr. Benoit Beauchamp, professor of geology at the University of Calgary, says this study is significant because it’s the first time mercury has been linked to the cause of the massive extinction that took place during the end of the Permian, about 250 million years ago.
During the period, the natural buffering system in the ocean became overloaded with mercury, contributing to the loss of 95 per cent of life in the sea.
The mercury deposition rates could have been significantly higher in the late Permian when compared with today’s human-caused emissions. In some cases, levels of mercury in the late Permian ocean were similar to what is found near highly contaminated ponds near smelters, where the aquatic system is severely damaged, say researchers.
“We are adding to the levels through industrial emissions. This is a warning for us here on Earth today,” adds Beauchamp. In North America, at least, there has been a steady decline through regulations controlling mercury.
The generally accepted idea has been that volcanic eruptions burned though coal beds, releasing CO2 and other deadly toxins. Direct proof of this theory was outlined in a paper that was published by these same authors last January in Nature Geoscience.
No matter what happens, this study shows life’s tenacity. “The story is one of recovery as well. After the system was overloaded and most of life was destroyed, the oceans were still able to self clean and we were able to move on to the next phase of life,” says lead author Hamed Sanei, research scientist at Natural Resources Canada and adjunct professor at the University of Calgary.
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