The most accurate time frame for the end-Permian extinction event ever produced and a determination of the preceding changes in the Earth’s environment was presented by Seth D. Burgess and Samuel Bowring from Massachusetts Institute of Technology and Shu-zhong Shen with the Chinese Academy of Sciences in the Feb. 10, 2014, edition of the journal Proceedings of the National Academy of Sciences.
The scientists examined multiple samples of zircon taken from the Permian-Triassic boundary at Meishan, China and examined the relative content of lead and uranium. The researchers also analyzed the carbon content of the areas from which the zircons were found.
The scientists found that the end-Permian extinction event lasted between 12,000 and 60,000 years and began 251.94 million years ago. Full recovery of flora and fauna on Earth from the end-Permian extinction event took five million years. This research is considered to be the most accurate dating of the end-Permian time frame of the five different examinations performed since 2008.
The researchers also found that the end-Permian event was preceded by increased levels of carbon in the atmosphere, ocean temperature increase that was as high as 23 degrees Fahrenheit, a massive increase in the volume of the world’s oceans, and ocean acidification.
The researchers plan to apply their techniques to shorter past extinction events and to the present global warming situation in order to be able to predict the time it may take for the Earth to recover from the effects of global warming.