Age of the Deccan traps using 187Re–187Os systematics
Age of the Deccan traps using 187Re–187Os systematics
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DOI：
10.1016/s0012-821x(99)00110-7
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发表时间：
1999-07
影响因子：
5.3
通讯作者：
C. Allègre;J. Birck;F. Capmas;V. Courtillot
中科院分区：
文献类型：
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作者：
C. Allègre;J. Birck;F. Capmas;V. Courtillot
已对德干圈闭中暴露面积大、地层厚度大的一组玄武岩进行了 Os 同位素系统学研究。结果绘制在非常明确的 Re-Os 等时线上，对应于 65.6±0.3 Ma 的年龄（2σ 不确定性）。这个年龄与之前的 K-Ar 和 Ar-Ar 数据非常吻合。 Os 数据还暗示火山活动持续时间较短，这对地幔地球动力学应该具有重要意义。 187Os/188Os 初始比率通常为球粒状：0.12843±0.00047 (2σ)，表明交代作用和地壳污染在德干圈闭形成期间的 Re-Os 预算中仅发挥非常小的作用。
A suite of basaltic rocks sampled over a vast exposure and stratigraphic thickness in the Deccan traps has been investigated for Os isotopic systematics. The results plot on a very well defined Re–Os isochron corresponding to an age of 65.6±0.3 Ma (2σ uncertainty). This age is in excellent agreement with previous K–Ar and Ar–Ar data. Os data also imply a short duration of volcanism, which should have important implications on mantle geodynamics. The187Os/188Os initial ratio is typically chondritic: 0.12843±0.00047 (2σ) and indicates that metasomatism and crustal contamination played only a very minor role in the Re–Os budget during formation of the Deccan traps.