Chinese researchers find new mechanism for mass extinction 250 mln yrs ago
HEFEI, April 8 (Xinhua) -- Chinese researchers found that the global dispersion of Ni-rich aerosols could be an important factor in a mass extinction that occurred 250 million years ago, Science and Technology Daily reported Thursday.
The end-Permian mass extinction (EPME) was the most severe biotic crisis in history, eliminating more than 90 percent of marine and 75 percent of terrestrial species. Scientists believed that the eruption of the Siberian Traps large igneous province (STLIP) had been the primary trigger for the catastrophe.
Recent studies showed that the STLIP eruption started about 300,000 years before the mass extinction, but the mechanism between the two events remained unsolved.
The researchers, led by Prof. Shen Yan'an from School of Earth and Space Sciences, University of Science and Technology of China in east China's Anhui Province, analyzed the abundance and composition of Ni isotopes in Permian-Triassic sedimentary rock layers from the Buchanan Lake section in the Sverdrup Basin of Arctic Canada.
The data indicated that the composition of Ni isotopes in the Sverdrup Basin clearly recorded the movement process of Ni-rich aerosols from the STLIP eruption via atmosphere transport to the sedimentation into the ocean and the land.
The result suggested that the large-scale sedimentation of Ni-rich aerosols at that time had both greatly consumed the oxygen in the ocean and resulted in ocean acidification and anoxia and deteriorated the environment on land for terrestrial organisms.
The research was recently published in the journal Nature Communications. Enditem