The Taatsiin Gol Basin in Mongolia is a key area for understanding the evolution and dispersal of Central Asian mammal faunas during the Oligocene and early Miocene. After two decades of intense fieldwork, the area is extraordinarily well sampled and taxonomically well studied, yielding a large dataset of 19,042 specimens from 60 samples. The specimens represent 176 species-level and 99 genus-level taxa comprising 135 small mammal species and 47 large mammals. A detailed lithostratigraphy and new magnetostratigraphic and radiometric datings provide an excellent frame for these biotic data. Therefore, we test and evaluate the informal biozonation scheme that has been traditionally used for biostratigraphic correlations within the basin. Based on the analysis of the huge dataset, a formalised biostratigraphic scheme is proposed. It comprises the Cricetops dormitor Taxon Range Zone (Rupelian), subdivided into the Allosminthus khandae Taxon Range Subzone and the Huangomys frequens Abundance Subzone, the Amphechinus taatsiingolensis Abundance Zone (early Chattian), the Amphechinus major Taxon Range Zone (late Chattian), subdivided into the Yindirtemys deflexus Abundance Subzone and the Upper Amphechinus major T. R. Z., and the Tachyoryctoides kokonorensis Taxon Range Zone (Aquitanian). In statistical analyses, samples attributed to these biozones form distinct clusters, indicating that each biozone was also characterised by a distinct faunal type.

中文翻译：

---

蒙古湖谷的渐新世和中新世早期哺乳动物生物地层学。

蒙古的Taatsiin Gol盆地是了解渐新世和中新世早期中亚哺乳动物群的演化和扩散的重要区域。经过二十年的紧张野外工作，对该区域进行了非常出色的采样和分类学研究，从60个样本中获得了19,042个样本的大型数据集。这些标本代表176个物种级别和99个属级别的分类单元，包括135个小型哺乳动物物种和47个大型哺乳动物。详细的岩相地层学以及新的地层学和放射学测年法为这些生物数据提供了极好的框架。因此，我们测试和评估了传统上用于流域内生物地层相关性的非正式生物分区方案。在对庞大数据集进行分析的基础上，提出了一种形式化的生物地层学方案。它包括Cricetops休眠类群分类区（Rupelian），细分为同种异花草类群分类区和黄Huang属丰度子区，Amphechinus taatsiingolensis富集区（早期查天），Amphechinus主要类群分布区（Chattian后期），细分为Yindir丰度分区和主要的安非他命TRZ，以及Tachyoryctoides kokonorensis分类群范围（阿基坦）。在统计分析中，归因于这些生物区的样本形成了不同的簇，这表明每个生物区还具有不同的动物类型。