In “The Great Dying” 250 million years ago, the devastation came with runaway greenhouse warming
The geology of Griesbach Creek in the Arctic tells an ancient tale of slow extinction. Source NSF.
A reposted National Science Foundation press release.
The deadliest mass extinction of all took a long time to kill 90 percent of Earth’s marine life–and it killed in stages–according to a newly published report.
It shows that mass extinctions need not be sudden events.
Thomas Algeo, a geologist at the University of Cincinnati, and 13 colleagues have produced a high-resolution look at the geology of a Permian-Triassic boundary section on Ellesmere Island in the Canadian Arctic.
Their analysis, published today in the Geological Society of America Bulletin [abstract here], provides strong evidence that Earth’s biggest mass extinction phased in over hundreds of thousands of years.
About 252 million years ago, at the end of the Permian period, Earth almost became a lifeless planet.
Around 90 percent of all living species disappeared then, in what scientists have called “The Great Dying.”
Algeo and colleagues have spent much of the past decade investigating the chemical evidence buried in rocks formed during this major extinction.
The world revealed by their research is a devastated landscape, barren of vegetation and scarred by erosion from showers of acid rain, huge “dead zones” in the oceans, and runaway greenhouse warming leading to sizzling temperatures.