Siberian Volcanic Eruptions Triggered End-Permian Mass Extinction, New Study Confirms

Wednesday, June 23, 2021

The end-Permian mass extinction — the most severe extinction event in the past 540 million years — was caused by massive volcanic eruptions in what is now Siberia, according to new research.

“The end-Permian mass extinction, which occurred about 252 million years ago, was the most severe biotic crisis in the Phanerozoic Eon, eliminating more than 90% of marine and 75% of terrestrial species,” said senior author Dr. Yanan Shen from the University of Science and Technology of China and colleagues.

“The Siberian Traps large igneous province is widely hypothesized to have been the primary trigger for the catastrophic environmental deterioration driving the extinction event.”

“Potential kill mechanisms triggered by emplacement of the Siberian Traps magmas include global warming, ultraviolet radiation exposure, hypercapnia, ocean acidification and anoxia, and toxic metal release.”

In the study, the researchers analyzed the Permian-Triassic sedimentary rocks from the Buchanan Lake section in the Sverdrup Basin, Canadian High Arctic.

They found that the samples have the lightest nickel isotope ratios ever measured in sedimentary rocks.

The only plausible explanation is that the nickel was sourced from the volcanic terrain, very likely carried by aerosol particles and deposited in the ocean, where it dramatically changed the chemistry of seawater and severely disrupted the marine ecosystem.

“The study results provide strong evidence that nickel-rich particles were aerosolized and dispersed widely, both through the atmosphere and into the ocean,” said co-author Dr. Laura Wasylenki, a researcher at Northern Arizona University.

“Nickel is an essential trace metal for many organisms, but an increase in nickel abundance would have driven an unusual surge in productivity of methanogens, microorganisms that produce methane gas. Increased methane would have been tremendously harmful to all oxygen-dependent life.”

“Our data provide a direct link between global dispersion of nickel-rich aerosols, ocean chemistry changes and the mass extinction event,” she added.

“The data also demonstrate that environmental degradation likely began well before the extinction event — perhaps starting as early as 300,000 years before then.”

“Prior to this study, the connection between Siberian Traps flood basalt volcanism, marine anoxia and mass extinction was rather vague, but now we have evidence of a specific kill mechanism.”

“This finding demonstrates the power of nickel isotope analyses, which are relatively new, to solve long-standing problems in the geosciences.”

The results were published in the journal Nature Communications.

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M. Li et al. 2021. Nickel isotopes link Siberian Traps aerosol particles to the end-Permian mass extinction. Nat Commun 12, 2024; doi: 10.1038/s41467-021-22066-7

Source: www.sci-news.com/