A study published today in Nature Geoscience1 suggests that one trigger for the near-apocalyptic 'great die-off', which killed 96% of marine species and 70% of land-based vertebrate organisms, was a volcanic explosion in coal and shale deposits in Siberia. Within days, ash from the eruption, raining down onto the Canadian Arctic, sucked oxygen from the water and released toxic elements.
...
"The magma went through a juicy bit of crust that it can release a lot of nasty things from," says Paul Wignall, a palaeontologist at the University of Leeds, UK, who studies mass extinction events.
...
This may have been the tipping point, says Wignall. Studies have suggested the volcanoes released 3 trillion tonnes of carbon, enough to trigger massive climate change. The eruptions also caused acid rain and emitted sufficient halogens to create an ozone hole, he says. Toxic fly ash, on top of all this, may have been the final blow.
"I can't suggest that this is the answer to the mass extinction story, but it is a new component to it," he says. "It is like throwing the kitchen sink at the world."
Studiot said:This book detailing the 30 odd years of study leading up to this theory and written by one of its leading architects, is absolutely fascinating.
http://palaeo.gly.bris.ac.uk/essays/permian.html
nucleus said:Another article:
http://www.ucalgary.ca/news/utoday/january24-2011/biggestextinction
(from the abstract: Grasby et al. Catastrophic dispersion of coal fly ash \par into oceans during the latest Permian extinction. Nat Geosci (2011) vol. 4 (1) pp. 1-4)Here we present analyses of terrestrial carbon in marine sediments that suggest a substantial amount of char was deposited in Permian aged rocks from the Canadian High Arctic immediately before the mass extinction. Based on the geochemistry and petrology of the char, we propose that the char was derived from the combustion of Siberian coal and organic-rich sediments by flood basalts, which was then dispersed globally. The char is remarkably similar to modern coal fly ash, which can create toxic aquatic conditions when released as slurries. We therefore speculate that the global distribution of ash could have created toxic marine conditions.
IIRC Alan Sedgewick. Since there are few fossils in the Permian of the UK Sedgewick needed somwhere that was both fossiliferous and had a continuous sequence - with few diastems or disconformities. I believe he went on an expedition to the Urals where he found such a sequence near Perm.billiards said:The book actually goes right back to before even Lyell, and discusses the geologist who first identified the Permian period (can't remember his name off the top of my head) and how Lyell's rejection of catastrophism held back the study of mass extinctions for a century.
The End Permian Mass Extinction, also known as the Great Dying, was caused by a combination of several factors. The main cause is believed to be a series of massive volcanic eruptions in what is now Siberia, which released large amounts of greenhouse gases into the atmosphere. This led to global warming, ocean acidification, and a decrease in oxygen levels in the oceans. Other contributing factors may have included asteroid impacts and changes in ocean currents.
The End Permian Mass Extinction is estimated to have lasted for around 200,000 years, making it the longest and most severe mass extinction event in Earth's history. The effects of the event were felt for millions of years after, as it took a long time for the Earth's ecosystems to recover and for new species to emerge.
It is estimated that around 90% of all marine species and 70% of all terrestrial species went extinct during the End Permian Mass Extinction. This includes a large number of plant and animal species, as well as many types of marine organisms such as corals, trilobites, and brachiopods.
Yes, some species did survive the End Permian Mass Extinction. These include certain species of fish, reptiles, and insects, as well as some plant species. However, the majority of surviving species were greatly affected by the event and had to adapt to the new environmental conditions in order to survive.
The End Permian Mass Extinction had a significant impact on the Earth's environment. The release of greenhouse gases led to a drastic increase in global temperatures, and the acidification of the oceans caused widespread extinction of marine life. The event also greatly altered the Earth's land and plant communities, as well as the composition of the atmosphere and the chemistry of the oceans. It took millions of years for the Earth's environment to recover and for new species to evolve and fill the niches left by those that went extinct.