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研究进展

冯庆来等,PRECAMBRIAN RESEARCH,2021

发表时间:2021-11-25编辑:王德珲点击:

Fossil evidence provides new insights into the origin of the Mesoproterozoic ministromatolites

作者

Wang, T (Wang, Tan)   Feng, QL (Feng, Qinglai)   Huang, YF (Huang, Yafei)  

366  

文献号

106426

DOI

10.1016/j.precamres.2021.106426

出版时间

NOV 2021

文献类型

Article

摘要

Although the biogenicity of the very common millimeter-sized ministromatolites in the Proterozoic has been noted, direct biotic evidence is missing, leading to the discussion of a chemical origin that differs from that of the cyanobacteria-related stromatolites in the Phanerozoic. Distinctive ministromatolites were recently discovered in a microbial dolostone interval of the Mesoproterozoic Wumishan Formation, at Lingyuan, North China. Thin section examination of the ministromatolites reveals the presence of abundant coccoidal microfossils ranging 10-30 mu m in diameter. Petrofabric analysis shows that the ministromatolites experienced three periods of diagenetic silicification, and that the microfossils are exclusively preserved within early diagenetic chert. This supports the view that silicification penecontemporaneous with mat growth is the key to unique preservation of microfossils. In contrast, the absence of microfossils in most Precambrian carbonate stromatolites may well be interpreted as the lack of hydrochemical conditions favorable for early silicification. Although chemically-formed fibrous carbonate minerals are the dominant components of these ministromatolites, the presence of abundant microfossils indicates that the role of microorganisms in the formation of ministromatolites has previously been underestimated. Therefore, this research suggests that Mesoproterozoic ministromatolites were not solely chemical products but consist of complex associations of both biotic and chemical fabrics.

关键词

 

作者信息

通讯作者地址

Feng, Qinglai    

(通讯作者)

China Univ Geosci, State Key Lab Geol Proc & Mineral Resources, Wuhan 430074, Peoples R China    

 

电子邮件地址

qinglaifeng@cug.edu.cn  

类别/分类

研究方向

Geology

基金资助