Permian Extinction
Michael Nelson
Abstract: The end Permian extinction was the greatest of all extinctions in Earth's history. It is estimated that as many as 95% of all species were annihilated compared to the well known K/T extinction which only about 70% of all species went extinct. Many hypotheses has been brought forth to explain this significant mass extinction. They vary from global warming to global cooling. Whether it was large scale volcanism in Russia or some kind of impact event that led to the extreme change in environment? Currently, there are several hypotheses to explain the change; including, major volcanism in Russia, methane expulsion, or a bolide impact.
Figure 1: Showing Extinctions throughout Geologic Time, (from www.globalchange.umich.edu/.../ complex_life.html)
I. What species and families went extinct?
a. Oceanic
b. Terrestrial
II. Current hypotheses of the extinction
a. Volcanism in Russia
b. Bolide Impact
c. Others (etc)
Conclusion
Figure 2: Triassic-Permian Boundary, Meishan, China (Hallam and Wignall, 1997).
Figure 3: Tesero Road, Italy, (Hallam and Wignan, 1997)
References:
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