Abstract

Sm–Nd isotope–geochemical studies of the Cenozoic sand deposits of the Muya Depression (eastern flank of the Baikal rift zone), which is located on the border of the Charo–Olekminskii Geoblock of the Aldan Shield and the Anamakit–Muya Zone of the Baikal–Muya Fold Belt, were carried out. The Nd model ages t_Nd(DM) were obtained for most of the sand samples from the Muya Depression in the range of 1.7–1.5 Ga (ɛ_Nd(0) = –12.0…–13.3). According to the Nd isotopic characteristics, they are most similar to the metasedimentary rocks of the Gorbylok Sequence of the Bambui–Olindin Subzone and the Dzhaltuk Group of the Muya Subzone of the Anamakit–Muya Zone, which were most likely their source. In this case, the sedimentary material, primary for the Cenozoic sand of the Muya Depression, was transported over a relatively short distance.

中文翻译：

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木雅坳陷（贝加尔湖裂谷带东翼）新生代砂矿床钐钕同位素系统学

摘要

穆亚凹陷（贝加尔湖裂谷带东翼）新生代砂矿床 Sm-Nd 同位素地球化学研究贝加尔湖-穆亚褶皱带，进行了。Nd 模型年龄t _Nd(DM)是从木亚坳陷的 1.7-1.5 Ga (ɛ _Nd(0) = –12.0…–13.3）。根据Nd同位素特征，它们与Bambui-Olindin亚带Gorbylok层序变质沉积岩和Anamakit-Muya带Muya亚带Dzhaltuk群最相似，最有可能是它们的来源。在这种情况下，主要为木雅坳陷新生代砂岩的沉积物质在相对较短的距离内运移。