峨嵋山暗色岩
外觀
峨嵋山暗色岩(英語:Emeishan Traps)又譯峨嵋山玄武岩,另一名稱是二疊紀峨嵋山大火成岩省(Permian Emeishan Large Igneous Province),是個大火成岩省,由溢流玄武岩所形成,位於中國四川省。
歷史
[編輯]峨嵋山暗色岩形成於2億6000萬年前,是由大型熱柱火山爆發,形成的多層火成岩所構成。在峨嵋山暗色岩火山爆發後不久,約2億5100萬年前,規模更大型的西伯利亞暗色岩形成。峨嵋山大火成岩省的規模超過30萬平方公里,足以對全球生態系統造成影響,因此被認為與瓜德魯普統末滅絕事件(或稱開匹坦期末滅絕事件)有關。
萬森·庫爾提歐(Vincent Courtillot)與其他科學家認為,峨嵋山暗色岩火山爆發與瓜德魯普統末滅絕事件幾乎同期發生,峨嵋山暗色岩應是這次滅絕事件的主因。另一派理論認為,這次滅絕事件是由小行星或彗星撞擊地球造成;更具爭議的理論則認為,峨嵋山暗色岩與其他大型火山爆發本身是由撞擊事件所造成[1]。
備註
[編輯]- ^ 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.
參考資料
[編輯]- 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 Uranium-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.