Silicified shallow-water marine carbonate deposits of the Proterozoic Debengda Formation (the Olenek Uplift, northeastern Siberia) contain well preserved microfossils. One or two distinct assemblages consists only of filamentous Siphonophycus microfossils, which are presumably the extracellular sheaths of hormogonium cyanobacteria. The other is dominated by coccoidal microfossils, first by the entophysalidacean cyanobacterium Eoentophysalis. The coccoidal assemblage was recognized in the layered carbonate precipitate structures of a superficially stromatolite appearance. Despite its simple composition, the microfossil assemblage supports the generally accepted Mesoproterozoic (middle Riphean) age of the Debengda Formation. This conclusion corresponds to the available data on isotopic geochronology, and to the composition of columnar stromatolites from the Dehengda Formation. Both the structural features and carbon isotopic composition of its rocks are comparable to those of rocks of known Mesoproterozoic age, but differ from the characteristics of definitely Neoproterozoic deposits.

中文翻译：

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西伯利亚东北部奥列尼克隆起的中生代（中里弗生）德本达组的Formation石中的微化石。

在元古代的Debengda组（西伯利亚东北部的Olenek隆起）的硅化浅水海相碳酸盐矿床中保存完好的微化石。一个或两个截然不同的组合仅由丝状微细丝状化石组成，大概是go属蓝细菌的细胞外鞘。另一个以球状微化石为主，首先是内生藻蓝藻蓝藻（Eoentophysalis）。在表面层状滑石层外观的层状碳酸盐沉淀结构中识别到了球状聚集体。尽管其组成简单，但微化石组合支持了Debengda组的中古生代（中生次生代）时代。该结论对应于同位素年代学的可用数据，以及德亨达组柱状叠层石的组成。它的岩石的结构特征和碳同位素组成与已知的中元古代的岩石相当，但是与新元古代沉积的特征不同。