Emeishan Traps

The Emeishan Traps constitute a flood basalt volcanic province, or large igneous province, in southwestern China, centered in Sichuan province. It is sometimes referred to as the Permian Emeishan Large Igneous Province or variations of that term.

The Traps

Like other volcanic provinces or "traps," the Emeishan Traps are multiple layers of igneous rock laid down by large mantle plume volcanic eruptions. The eruptions that produced the Emeishan Traps began c. 260 million years ago (Ma). In volume, the Emeishan Traps are dwarfed by the massive Siberian Traps, which occurred, in terms of the geological time scale, not long after, at c. 251 Ma. Nonetheless the Emeishan Traps eruptions were serious enough to have global ecological and paleontological impact. The Emeishan Traps are associated with the so-called end-Guadalupian or end-Capitanian mass extinction, the extinction of animal and plant life that occurred at the end of the Capitanian stage of the Guadalupian epoch of the Permian period.

As such, the Emeishan Traps form one aspect of the larger scientific debate on the causes of mass extinctions. [Yukio Isozaki, "Plume Winter Scenario for Biosphere Catastrophe: The Permo-Trassic Boundary Case," in: Yuen et al., pp. 409-440.] The synchrony between the Emeishan Traps and the end-Guadalupian extinction has been taken to support the argument, supported by Vincent Courtillot among many others, that volcanism is the main driver of mass extinctions. In the context of the opposing argument, that mass extinctions are caused by meteor or comet impact events, a hypothesis has been proposed that the Emeishan Traps eruptions (and other traps-generating flood basalt eruptions) are themselves caused by impact events [Adrian P. Jones, David G. Price, Paul S. DeCarli, and Richard Clegg, "Impact Decompression Melting: A Possible Trigger for Impact Induced Volcanism and Mantle Hotspots?", in: Koeberl and Martinez-Ruiz, pp. 91-120; esp. pp. 110-11.] — though the hypothesis is highly controversial.

ee also

* Deccan Traps
* Mount Emei

Notes

References

* Dobretsov, N. L. (2005) "Large Igneous Provinces of Asia (250 Ma): Siberian and Emeishan traps (plateau basalts) and associated granitoids." "Geologiya i geofizika," Vol. 46, pp. 870-890.
* He, Bin, Yi-Gang Xu, Sun-Ling Chung, Xiao-Long Huang, and Ya-Mei Wang. (2003) "Sedimentary evidence for a rapid kilometer-scale crustal doming prior to the eruption of the Emeishan flood basalts." "Earth and Planetray Science Letters," Vol. 213, pp. 391-405.
* He, Bin, Yi-Gang Xu, Xiao-Long Huang, Zhen-Yu Luo, Yu-Ruo Shi, Qi-Jun Yang, and Song-Yue Yu. (2007) "Age and duration of the Emeishan flood volcanism, SW China: Geochemistry and SHRIMP zircon U-Pb dating of silicic ignimbrites, post-volcanic Xuanwei Formation and clay tuff at the Chaotian section." "Earth and Planetary Science Letters" Vol. 255, pp. 306-23.
* Koeberl, Christian, and Francisca C. Martinez-Ruiz, eds. (2003) "Impact Markers in the Stratigraphic Record." New York, Springer-Verlag.
* Yuen, David A., Shinegoru Maruyama, Shun-Ichiro Karato, and Brian F. Windley, eds. (2007) "Superplumes: Beyond Plate Tectonics." New York, Springer-Verlag.

External links

* [http://argonlab.gl.ntu.edu.tw/papers/Lo-Emeishan.pdf Age of the Emeishan Flood Magmatism and Relations to Permian-Triassic Boundary Events.]