青海省湟中区东岔沟克素尔组叠层石分类及地层对比

叠层石被广泛认为是地球上的一些最古老的生命痕迹，是研究地球早期生命的重要窗口。作为前寒武纪地层中的唯一常见化石，可以作为地层对比的标志，特别是中、新元古代盆地间的地层对比。青海省中祁连地层分区东岔沟村花石山群克素尔组以白云质碳酸盐岩组合为主，赋存大量叠层石。依据曹瑞骥和袁训来总结的分类方法，在研究区识别出9种不同的叠层石属，分别为：Baicalia、Chihsienella、Anabaria、Tielingella、Conicodomenia、Tungussia、Colonnella、Stratifera和Cryptozoon。研究区叠层石组合与中元古界上部蓟县系铁岭组叠层石组合具有明显的可比性，与国内其他地区的中元古代晚期—新元古代早期叠层石组合也有很强的相似性，据此推测花石山群克素尔组的年代大致为中元古代晚期。青海叠层石的报道将为我国和世界范围内中、新元古代叠层石的分布提供新产地的数据，常见叠层石属、种的垂直分布延限也有新的化石证据，对提升地层对比的精度具有重要意义。

Classification and stratigraphic correlation of stromatolites in Kesuer Formation, Dongchagou Village, Huangzhong District, Qinghai Province

Stromatolites, often considered among the oldest traces of life on Earth, provide valuable paleontological insights for chronostratigraphic correlation. They are particularly useful for stratigraphic correlation in Mesoproterozoic basins. The Kesuer Formation, part of the Huashishan Group in Dongchagou Village, Huangzhong District, Xining City, Qinghai Province, primarily consists of dolomitic carbonate assemblages with a large quantity of stromatolites. According to the classification method summarized by Cao Ruiji and Yuan Xunlai, nine distinct stromatolite genera have been identified in this area: Baicalia, Chihsienella, Anabaria, Tielingella, Conicodomenia, Tungussia, Colonnella, Stratifera and Cryptozoon. This stromatolite assemblage closely resembles the Late Mesoproterozoic Tieling Formation stromatolite assemblage in the Jixian System, and shares similarities with Late Mesoproterozoic to Early Neoproterozoic strata stromatolite assemblage in China. As a result, the age of the Kesuer Formation in the Huashishan Group can be determined as Late Mesoproterozoic. The report of Qinghai stromatolites broadens the known distribution of Mesoproterozoic stromatolites in China and globally, updating the vertical distribution of common stromatolite genera and species. These findings hold significant implications for stratigraphic correlation.