Mass extinction that wiped out 90% of species 250 million years ago was triggered by a volcanic eruption that plunged Earth into a freezing winter, study finds
- The “Great Dying” is normally associated with large-scale volcanism in Siberia
- CO₂ release from flood basalts thought to trigger severe warming
- But research by the Chinese Academy of Sciences suggests that the cooling came first
- Evidence came in the form of copper-rich rocks from China’s Sichuan province
- The team believed average global temperatures initially dropped by about 4 ° C (7.2 ° F)
- Life in the Permian would therefore have been subject to rapid climate change
The “great death” of 250 million years ago – which wiped out 90% of living species – was triggered in part by an eruption that generated a worldwide volcanic winter.
This concludes the research carried out by the Chinese Academy of Sciences, which studied contemporary copper-rich deposits in the province of Sichuan, in southern China.
Anomalies in these rocks – which were covered with layers of volcanic ash – suggest they were formed or affected by sulfur-rich emissions from nearby volcanoes.
When injected into the atmosphere, sulfur aerosols work to reflect incoming sunlight into space and change clouds, resulting in a rapid cooling effect.
Researchers believe volcanism in China may have temporarily lowered average global temperatures by about 4 ° C (7.2 ° F).
The “great death” of 250 million years ago, which wiped out 90% of living species, was caused in part by an eruption that generated a worldwide volcanic winter. That’s the conclusion of a study conducted by the Chinese Academy of Sciences, which investigated deposits of rich copper (including malachites) unearthed in Sichuan, southern China (pictured)
Anomalies in these rocks – which were covered with layers of volcanic ash – suggest they were formed or affected by sulfur-rich emissions from nearby volcanoes, as pictured
The team suggests that sulfur-rich volcanism may have been a previously unknown stressor in preparing for the Late Permian extinction 250 million years ago, contributing to the loss of species during this devastating event.
“As we take a closer look at the geological records around the time of the Great Extinction,” began article author and geologist Michael Rampino of New York University.
“We find that the late Permian global environmental catastrophe can have multiple causes among marine and non-marine species.”
The extinction of the Late Permian is usually linked to different volcanic activity, especially the eruption of the flood basalts that make up Russia’s vast Siberian traps.
Rather than a brief explosive episode, the formation of this “great igneous province” saw some 1 million cubic miles (4 million cubic kilometers) of rock set up as flowing lava over two million years. .
These eruptions are believed to have caused considerable environmental stress – including severe global warming resulting from the release of carbon dioxide and a reduction in the oxygen content of the oceans, suffocating marine life.
However, the team’s findings suggest that the period of volcanic-induced warming may have been preceded by the quite opposite stressor – a volcanic winter.
“Atmospheric aerosols of sulfuric acid produced by eruptions [in China] may have been the cause of a rapid global cooling of several degrees, before the severe warming observed throughout the Late Permian mass extinction interval, ”said Dr. Rampino.
Anomalies in late Permian rocks – which were covered with layers of volcanic ash – suggest they were formed or affected by sulfur-rich emissions from nearby volcanoes. In the photo: photomicrographs of inclusions in rocks, especially inclusions of sulfide in anhedral quartz (top row) and inclusions of molten copper in quartz fragments (bottom row)
WHAT WAS THE MASS EXTINCTION OF THE PERMIAN, KNOWN AS “THE GREAT DEATH” THAT KILLED 9 OUT OF 10 SPECIES?
About 248 million years ago, the Permian Period ended and the Triassic Period began on Earth.
The Permian mass extinction, nicknamed “The Great Dying,” marks the boundary between these two geological eras.
This catastrophic event saw almost all of life on Earth wiped out.
Scientists believe that about 95% of all marine life perished in the mass extinction, and less than a third of life on earth survived the event.
In total, it is believed that 90 percent of all life has been wiped out.
All life on Earth today is descended from the roughly ten percent of animals, plants and microbes that survived the Permian mass extinction.
Previously, it was believed that a huge eruption had blanketed the Earth in thick smog, preventing the sun’s rays from reaching the planet’s surface.
However, new findings suggest that a massive volcanic eruption that lasted nearly a million years released a huge reservoir of deadly chemicals into the atmosphere that stripped the Earth of its ozone layer.
This eradicated the only protection the inhabitants of Earth had from the deadly UV rays of the sun.
This form of high-energy radiation can cause significant damage to living organisms, causing the death toll to skyrocket.
“Large-scale eruptions near the southern China bloc synchronized with the Late Permian mass extinction reinforce the hypothesis that the large igneous province of the Siberian traps may not have been the only trigger.” , wrote the researchers in their article.
“This work strongly suggests that there was rapid cooling, probably above 4 ° C. [7.2°F] – on a global average and in the southern China bloc – followed by a sudden warming at the end of the Permian, ”they explained.
“Rapid cooling in addition to longer-term warming increases the climatic extremes experienced by terrestrial ecosystems.
“This reinforces the fact that environmental degradation from rapid climate change was an important mechanism of destruction during the Late Permian biotic crisis.”
The full results of the study were published in the journal Science Advances.
Chinese Academy of Sciences researchers studied copper-rich deposits unearthed in southern China’s Sichuan province
EARTH HAS HAD FIVE GREAT EXTINCTION EVENTS WITH THE MOST FAMOUS Asteroid killing a dinosaur
Five times the vast majority of world life has been suffocated in what have been called mass extinctions.
Mass extinction of the late Ordovician
The first of the five great traditional extinction events, around 540 million years ago, was probably the second in importance. Most of the life was in the sea at the time and about 85% of these species are extinct.
Mass extinction of the Upper Devonian
About 375 to 359 million years ago, major environmental changes caused a protracted extinction event that wiped out major groups of fish and stopped the formation of new coral reefs for 100 million years.
Five times the vast majority of world life has been suffocated in what have been called mass extinctions. Perhaps the most famous is the Late Cretaceous, which wiped out dinosaurs. Artist’s impression
Mass extinction of the late Permian (the Great Dying)
The largest extinction event and the one that most affected the ecology of the Earth took place 252 million years ago. Up to 97% of the species that leave a fossil record are gone forever.
Late Triassic mass extinction
Dinosaurs first appeared in the Lower Triassic, but large amphibians and mammal-like reptiles were the dominant land animals. The rapid mass extinction that occurred 201 million years ago has changed that.
Mass extinction at the end of the Cretaceous
An asteroid crashed into Earth 66 million years ago and is often accused of ending the reign of the dinosaurs.