The Permian extinction – also known as the “Great Extinction” – occurred as a result of massive volcanic eruptions in Siberia. This was finally proved by scientists in a new study.
Researchers have found a direct link between the spread of aerosols with high nickel content on the planet, which led to a change in the chemical composition of the ocean, and global extinction, which devastated the Earth at the end of the Permian era.
The Permian mass extinction is one of five mass extinctions. The border between the Permian and Triassic geological periods was drawn along it (it also separates the Paleozoic and Mesozoic eras). The age of this boundary according to the modern geochronological scale is 251.902 ± 0.024 Ma.
It is one of the largest disasters in the biosphere in the history of the Earth, which led to the extinction of 96% of all marine species and 73% of terrestrial vertebrate species. The catastrophe became the only known mass extinction of insects as a result of which about 57% of genera and 83% of species of the entire class of insects became extinct. Due to the loss of such a large number and diversity of species, the restoration of the biosphere took a much longer period of time compared to other disasters that led to extinctions.
It is believed that trap magmatism in Siberia is responsible for the extinction. During this process, a huge volume of magma is poured onto the surface and a large amount of aerosols are thrown out. Scientists have confirmed the theory.
Experts in the laboratory carried out isotopic analysis of nickel from Late Permian sedimentary rocks. They were found in the territory of Arctic Canada. As a result of the study, it turned out that these samples contain the lowest ratio of nickel isotopes ever found on the planet. The reason is that this nickel originated from volcanic areas, from where the metal was carried away in the form of an aerosol into the ocean. By settling on water, nickel drastically changed its chemical composition and had a destructive effect on the marine ecosystem.
The growth of nickel concentration over the millennia took place against the background of vigorous activity of microorganisms in the ocean. As a result, this led to the depletion of oxygen in the seas and the formation of giant dead zones. The global extinction process was launched due to the peak of volcanic magmatism in Siberia. Ultimately, this led to the release of carbon dioxide and methane and, as a result, to a sharp climate change and an almost complete oxygen depletion of the ocean. This caused the mass extinction of marine animal species.