SHRIMP U-Pb zircon age of tuff at the bottom of the Lower Cambrian Niutitang Formation, Zunyi, South China
SHRIMP U-Pb zircon age of tuff at the bottom of the Lower Cambrian Niutitang Formation, Zunyi, South China
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DOI：
10.1007/s11434-008-0084-0
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发表时间：
2008-02
影响因子：
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通讯作者：
Mingzhong Zhou;Taiyi Luo;Zheng‐Xiang Li;Huifang Zhao;Han Long;Yong Yang
中科院分区：
文献类型：
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作者：
Mingzhong Zhou;Taiyi Luo;Zheng‐Xiang Li;Huifang Zhao;Han Long;Yong Yang
对遵义松林地区下寒武统牛蹄塘组底部凝灰岩进行SHRIMP U-Pb年代学研究，得出平均206pb /238U年龄为518±5 Ma。与松林基底牛铁塘组上覆多金属ni - mo - pge富层537 ~ 542 Ma的Re-Os年龄相比，Re-Os年龄明显年轻，说明Re-Os年龄可能代表了ni - mo - pge富层原始岩浆房的年龄，而不是地层的形成年龄。盆地内地层对比也表明澄江生物群的绝对年龄小于518±5 Ma。结合云南梅树村剖面朱家庆组中一村段k -膨润土的SHRIMP U-Pb锆石年龄，为华南扬子地台下寒武统提供了时间约束。
A SHRIMP U-Pb zircon geochronology study of the tuff at the bottom of the Lower Cambrian Niutitang Formation at Songlin, Zunyi, South China yielded a mean206Pb/238U age of 518±5 Ma. It is significantly younger than the Re-Os ages of 537–542 Ma for the overlying polymetallic Ni-Mo-PGE-rich layer in the basal Niutitang Formation at Songlin, suggesting that the Re-Os ages might represent that of the original magma chamber for the Ni-Mo-PGE-rich layer rather than the formation age of the strata. The intra-basinal stratigraphic correlation also implies that the absolute age of the Chengjiang biota should be younger than 518±5 Ma. Our new result, together with the SHRIMP U-Pb zircon age for the K-bentonite in the Zhongyicun member of the Zhujiaqing Formation at the Meishucun section, Yunnan Province, provides a temporal constraint for the Lower Cambrian of the Yangtze Platform in South China.