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
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