Major volcanic eruptions may have caused mass extinctions throughout Earth’s history, like the one that destroyed the dinosaurs around 66 million years back.
Currently, the best theory to describe the mass extinction that saw the finish of the dinosaurs shows that it had been triggered whenever a massive asteroid impacted Earth in what’s now the Chicxulub region of the Gulf coast of florida. However, new research shows that the asteroid could have had an ‘accomplice’ in this extinction event by means of volcanic activity.
This new research, which re-examined volcanic explosions with regards to the quantity of lava they spewed, supplies the most compelling evidence yet that the correlation between volcanic activity in geological records and the death of multiple species in the blink of a geological eye is not any coincidence.
“Our results ensure it is hard to disregard the role of volcanism in extinction,” assistant professor of Earth Sciences at Dartmouth University, Brenhin Keller, said in a statement. (opens in new tab)
The fossil record provides the fingerprint of five major mass extinctions, probably the most famous which is the the one that happened in the Cretaceous period which lasted between 145.5 and 65.5 million years back that killed the dinosaurs alongside around 76% of most Earth’s species.
Keller and his team found proof a kind of volcanic fingerprint called a flood basalt corresponding with the Cretaceous period mass extinction and three of another five mass extinctions recorded in Earth’s geological record.
Flood basalt is left out when the group of small volcanic eruptions or one titanic one rapidly flood vast regions of land with lava. This technique creates extensive parts of igneous rock in a step-like arrangement called ‘large igneous provinces’ which contain at the very least 100,000 cubic kilometers of magma.
Earth’s history already shows proof how volcanic eruptions of the magnitude could trigger a mass extinction.
A number of eruptions in Siberia around 252 million years back triggered what’s probably the most severe mass extinctions ever discovered the fantastic Permian Extinction. Of these eruptions, massive levels of skin tightening and were released in to the atmosphere killing 90% of most species and causing an environmental catastrophe.
Proof this violent and destructive volcanic activity is recorded in the Siberian Trap a big region of volcanic rock round the size of Australia.
Round the time of the Cretaceous period mass extinction, the Indian subcontinent was rocked by volcanic eruptions that created the Deccan plateau 7,000 feet (2,000 meters) of flat-lying basalt lava flows that cover a location of almost 190,000 square miles (500,000 square kilometers) in west-central India.
Similar to the strike of the Chicxulub impactor is proposed to possess done, this may experienced far-reaching global effects and may have filled the atmosphere of Earth with sunlight-blocking dust and toxic fumes, choking the dinosaurs along with other Cretaceous period species.
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The specific reason behind the extinction of the dinosaurs has been hotly debated for quite a while, however the discovery of the Chicxulub crater in the Gulf coast of florida and the massive impact that created it has turned into a ‘smoking gun’ dominating all the proposals.
“All the theories that attemptedto explain what killed the dinosaurs got steamrolled once the crater the asteroid had gouged out was discovered,” Keller said. “But there’s hardly any proof similar impact events that coincide with another mass extinctions despite decades of exploration.”
Along with lining up the very best available estimates of flood basalt eruptions with periods of drastic species extinction including however, not limited by the five mass extinctions the team also created randomly generated timelines to check 100 million similar patterns.
They discovered that significantly less than 1% of the simulated timelines agreed along with the actual record of flood basalts and extinctions, suggesting the partnership between massive volcanic eruptions and mass extinction isn’t just random chance.
These new findings may shift the total amount and only tremendous volcanic activity, however when it involves the Cretaceous die-out, the team thinks that both Deccan plateau eruption and the Chicxulub impactor could have acted as a ‘double-punch’ to get rid of the dinosaurs.
A paper detailing the team’s findings is published in the journal Proceedings of the National Academy of Sciences. (opens in new tab)