Fox News: Mass extinction event 2 billion years ago killed 99 percent of life on Earth, study says
Mass extinction event 2 billion years ago killed 99 percent of life on Earth, study says
There have been several mass extinction events during the planet's history, including the Cretaceous–Paleogene extinction event, arguably the best known one because of the death of the dinosaurs. Now, researchers may have discovered a new mass extinction event, one that happened 2.05 billion years ago and likely killed between 80 percent and 99.5 percent of all of life on Earth.
Published in PNAS, the study notes that a group of researchers looked at rocks in Hudson Bay, Canada that formed billions of years ago and found that there was a sharp drop in life 2.05 billion years ago. This happened in conjunction with the end of the Great Oxidation Event (GOE), a period between 2.4 billion and 2 billion years ago that saw a surge and ultimately, a huge drop in oxygen levels on the planet.
"Using insights from sulfur and barium isotope measurements, combined with radiometric ages from bracketing strata, we infer that the sulfate minerals studied here record ambient sulfate in the immediate aftermath of the GOE (ca. 2,018 Ma)," the study's abstract reads. "These sulfate minerals captured negative triple-oxygen isotope anomalies as low as ∼ −0.8‰. Such negative values occurring shortly after the GOE require a rapid reduction in primary productivity of >80%, although even larger reductions are plausible."
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Fox News: Mass extinction event 2 billion years ago killed 99 percent of life on Earth, study says Reviewed by Rohta on September 03, 2019 Rating: