| Autor: |
Ming-Xing Ling, Ren-Bin Zhan, Guang-Xu Wang, Yi Wang, Yuri Amelin, Peng Tang, Jian-Bo Liu, Jisuo Jin, Bing Huang, Rong-Chang Wu, Shuo Xue, Bin Fu, Vickie C. Bennett, Xin Wei, Xiao-Cong Luan, Seth Finnegan, David A.T. Harper, Jia-Yu Rong |
| Jazyk: |
angličtina |
| Rok vydání: |
2019 |
| Předmět: |
|
| Zdroj: |
Solid Earth Sciences, Vol 4, Iss 4, Pp 190-198 (2019) |
| Druh dokumentu: |
article |
| ISSN: |
2451-912X |
| DOI: |
10.1016/j.sesci.2019.11.001 |
| Popis: |
The end Ordovician mass extinction (EOME) was the second most severe biotic crisis in Phanerozoic, and has been widely linked to a major glaciation. However, robust geochronology of this interval is still lacking. Here we present four successive high-precision zircon U–Pb dates by isotope dilution thermal ionization mass spectrometry (ID-TIMS) for biostratigraphically well-constrained K-bentonites of a continuous Ordovician-Silurian boundary section at Wanhe, SW China. They include 444.65 ± 0.22 Ma (middle Dicellograptus complexus Biozone), 444.06 ± 0.20 Ma (lower Paraorthograptus pacificus Biozone), 443.81 ± 0.24 Ma (upper Tangyagraptus typicus Subzone), and 442.99 ± 0.17 Ma (upper Metabolograptus extraordinarius Biozone). Calculations based on sedimentation rates suggest a duration of 0.47 ± 0.34 Ma for the Hirnantian Stage, which is much shorter than previously thought (1.4 ± 2.05 Ma in the International Chronostratigraphic Chart ver. 2019/05). The new data also constrain the Hirnantian glacial maximum to ∼0.2 Ma, supporting that its brevity and intensity probably triggered the EOME. Keywords: ID-TIMS, K-bentonite, End Ordovician mass extinction (EOME), Hirnantian stage |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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