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华北中元古代高于庄组 ( 1 4- 1 5亿年 )的硅质叠层石中保存了完好的多种微生物化石。从这些叠层石的微细构造分析 ,成岩早期硅质矿物的交代作用为微体化石的原位保存起了很重要的作用。除部分居住者和浮游的分子外 ,两种丝状蓝藻 ( Siphonophycus inornatum和Eoschizothric composita)和两种球状蓝藻 ( Coccostratusdispergens和 Eoentophysalisbelcherensis)是这些藻席的主要建造者。以球状蓝藻 Eoentophysalis为主的藻席可能发育于潮下高能环境中 ;而以多种丝状蓝藻为主的藻席可能反映了当时的沉积环境为中—高潮间带的局部静止小水体
A variety of microbial fossils have been preserved in the siliceous stratigraphic rocks of the Middle Proterozoic Gaoyuzhuang Formation in North China (140-150 billion years). From the analysis of the microstructures of these stratigraphic rocks, the metasomatism of early silicic minerals played an important role in the in situ preservation of microfossils. Except for some occupants and planktonic molecules, two filamentous cyanobacteria (Siphonophycus inornatum and Eoschizothric composita) and two globular cyanobacteria (Coccostratus dispergens and Eoentophysalisbelcherensis) are the major builders of these algae. The algae mainly dominated by Eoentophysalis may develop in the subtidal high-energy environments. The algal blooms mainly dominated by many filamentous cyanobacteria may reflect that the sedimentary environment at that time was locally still small body of water in the mid-high tidal zone