The asteroid that collided with the Earth and wiped out the dinosaurs some 66 million years ago may have had an accomplice in the form of volcanic activity, according to research published in the October 2 edition of the journal Science.
According to Engadget, the paper’s authors believe the Chicxulub impact event could have accelerated volcanic eruptions in India, causing the release of toxic gas from a massive lava lake known as the Deccan Traps. The impact wouldn’t have caused the geologic activity at the 200,000 square mile lake, but it would have made it more intense.
Their findings indicate that the ongoing, slower-placed eruptions at the Deccan Traps doubled in output within 50,000 years of the Chicxulub impact. The impact and the volcanic activity would have been a one-two punch that lead to the extinction of the dinosaurs (and many other creatures) by covering the planet with noxious fumes and by radically changing the climate.
“Based on our dating of the lava, we can be pretty certain that the volcanism and the impact occurred within 50,000 years of the extinction, so it becomes somewhat artificial to distinguish between them as killing mechanisms: both phenomena were clearly at work at the same time,” lead researcher Paul Renne of the University of California-Berkeley said in a statement.
Okay, but which one really caused the mass extinction?
Renne, a professor-in-residence of earth and planetary science at the university and the director of the Berkeley Geochronology Center, added it would be “basically impossible” to pinpoint which of the two events was most responsible for the atmospheric effects that killed the dinosaurs, as both events “happened at the same time.”
He and his colleagues believe that the Chicxulub impact caused drastic changes to the volcano’s so-called plumbing system. Those changes resulted in widespread changes in both the chemistry and the frequency of the eruptions, resulting in a 500,000 year delay in the recovery of life after the end of the Cretaceous and the start of the Tertiary period.
Co-author Mark Richards, a UC Berkeley professor of earth and planetary science and the man who first proposed the link between the impact and activity at the Deccan Traps, said that he is uncertain which event is most responsible for the extinction of the dinosaurs. However, he noted that the link between all three events is becoming too strong to dismiss.
“If our high-precision dates continue to pin these three events – the impact, the extinction and the major pulse of volcanism – closer and closer together, people are going to have to accept the likelihood of a connection among them,” Richards explained. “The scenario we are suggesting – that the impact triggered the volcanism – does in fact reconcile what had previously appeared to be an unimaginable coincidence.”
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Image credit: Thinkstock
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