Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age
Application of carbon isotope chemostratigraphy to the Renison dolomites, Tasmania: a Neoproterozoic age
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DOI：
10.1080/08120099708728353
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发表时间：
1997-12
影响因子：
1.2
通讯作者：
M. Adabi
中科院分区：
文献类型：
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作者：
M. Adabi
这项研究使用碳同位素化学地层学提出了成功溪群和深红溪组的年龄在没有任何直接的放射性测年，古地磁或可靠的古生物学数据。δ 13 C值是针对蚀变最小的白云石样品测定的。根据粒度、阴极发光岩相学、最富集的δ 18 O值（>-2%）、低Mn/Sr比和低Fe和Mn浓度选择合适的样品。最年轻（1号）白云岩层中平均蚀变最小、13 C富集最多的微晶灰岩样品为+4.6%o。这是新元古代（但不是寒武纪）碳酸盐岩的典型特征。各白云岩样品的δ 13 C值均为正值（最高达+ 7.5%o），未观察到元古宙/寒武系界线的偏移特征。在所有研究的白云石样品中，δ 13 C值均为负值，这也表明在白云岩序列中不存在Sturtian和Varanger冰碛岩的相关物。那个...
This study uses carbon isotope chemostratigraphy to propose an age for the Success Creek Group and Crimson Creek Formation in the absence of any direct radiometric dates, palaeomagnetic or reliable palaeontological data. The δ13C values were determined for the least‐altered dolomite samples. Suitable samples were selected on the basis of grainsize, cathodoluminescence petrography, most enriched δ18O values (> ‐2%o) low Mn/Sr ratios and low Fe and Mn concentrations. The average least‐altered, most 13C‐enriched dolomicrite samples in the youngest (No. 1) dolomite horizon are + 4.6%o. This is typical of Neoproterozoic (but not Cambrian) carbonates. The δ13C values of all dolomite samples in the succession are significantly positive (up to + 7.5%o) and the excursion characteristic of the Proterozoic/Cambrian boundary has not been observed. The lack of negative δ13C values in all dolomite samples studied also suggests an absence of correlatives of Sturtian and Varanger tillites in the dolomite successions. The...