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Life (http://www.geofinds.com), (2006-11-5), 1(2): 15-22.
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Second, the onset of deep-marine anoxia appears to be synchronous, at the time resolution of conodont zones, in both low and high-latitude oceans. This suggests that deep-marine anoxia was generated quickly at many localities or, if it was originated at limited localities, oceanic circulation must have been rigorous to quickly spread the anoxic water across the entire deep ocean. Finally, this study supports that the end-Permian mass extinction was essentially a globally-synchronous event (Retallack, 2004; Twitchett et al., 2004). It started at the end of the C. yini zone in both shallow and deep marine environments at both high and low latitudes, and persisted into the H. parvus zone. The oceanic anoxia started at about the same time as the mass extinction in the deep marine environment, but postdated the extinction in shallow marine environment. This suggests that oceanic anoxia probably was not the major cause of the end-Permian mass extinction of marine organisms.
Acknowledgements Supported by National Natural Scientific Foundation of China (No. 40472015) and the State Key Laboratory of Modern Paleontology and Stratigraphy (No. 053102), as well as the Key Laboratory for Minerals and Resources, Chinese Academy of Sciences. ReferencesBasu, A.R., Petaev, M.I., Poreda, R.J., Jacobsen, S.B., and Becker, L., 2003. Chondritic Meteorite Fragments Associated with the Permian-Triassic Boundary in Antarctica: Science, 302: 1388-1392. Bowring, S. A., Erwin, D.H. , Jin, Y.G. , Martin, M.W., Davidek, K., Wang, W., 1998. U/Pb Zircon Geochronology and Tempo of the End-Permian Mass Extinction: Science, 280: 1039-1045. Crasquin-Soleau, S., Kershaw, S., 2005. Ostracod fauna from the Permian–Triassic boundary interval of South China (Huaying Mountains, eastern Sichuan Province): palaeoenvironmental significance: Palaeogeography, Palaeoclimatology, Palaeoecology, 217(1-2): 131-141. Erwin, D. H., 1994. The Permo–Triassic extinction: Nature, 367: 231-236. Isozaki, Y., 1997. Permo-Triassic boundary superanoxia and stratified superocean: records from lost deep sea: Science, 276: 235-238. Jiang, N.Y., and Qian, W. L., 1986. Sedimentary environments and biofacies of South China in Permian and cause of mass extinction. in Selected Papers from the 13th and 14th Annual Conventions of Paleontological Society of China: Anhui Science and Technology Publishing House: 167-188. Jin, Y.G., Shen, S.Z., Zhu, Z.L., Mei, S.L., Wang, W., 1996. The Selong Section, candidate of theglobal stratotype section and point of the Permian-Triassic boundary. in Yin, H. F., ed., The Palaeozoic-Mesozoic boundary candidates of the global stratotype section and point of the Permian-Triassic boundary: China University of Geosciences Press: 127-137. Kapoor, H.M., 1996. The Selong Section, candidate of theglobal stratotype section and point of the Permian-Triassic boundary, in Yin, H. F., ed., The Palaeozoic-Mesozoic boundary candidates of the global stratotype section and point of the Permian-Triassic boundary: China University of Geosciences Press: 99-110. |
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