辽西葫芦岛三道沟剖面张夏组鲕粒滩中高能核形石沉积特征及成因机制分析  

Sedimentary Characteristics and Genetic Mechanism of High-Energy Oncoids in Oolitic Shoal of Zhangxia Formation in Sandaogou Section,Huludao City,Liaoning Province

作　　者：黄海永 秦仁月 尹须伟 HUANG Haiyong;QIN Renyue;YIN Xuwei(School of Earth Science and Resources,China University of Geosciences (Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《西安石油大学学报（自然科学版）》2021年第4期13-25,共13页Journal of Xi’an Shiyou University（Natural Science Edition）

基　　金：国家自然科学基金项目(41492090);国家自然科学基金项目(40472065);国家自然科学基金项目(49802012)。

摘　　要：通过电子显微镜对辽西葫芦岛市三道沟剖面顶部鲕粒滩中发育的高能泥晶核形石进行观察,在低倍正交偏光显微镜下核形石皮层大多为明暗交替的纹层,少数不发育纹层,核心多为生物骨架化石碎片;高倍镜下,核形石皮层和核形石间凝块(clots)分别表现为密集的顺层排列,由不规则网状的归为葛万菌组合(Girvanella Group)的丝状钙化蓝细菌鞘化石构成,表明核形石形成于高能氧化水体中球状光合作用微生物席或微生物膜内的复杂的钙化作用和早期石化过程。The high-energy micritic oncoids developed in the oolitic shoal at the top of Sandaogou section in Huludao City,Liaoning Province,was observed by electron microscope.Under the low-power orthogonal polarizing microscope,the outer layer of the oncoids is mostly lightdark alternating laminae,a few do not develop laminae,and the core of them is mostly biological skeleton fossil fragments;Under the high-power orthogonal polarizing microscope,the outer layer of the oncoids and the clots between the oncoids are composed of the filamentous calcified cyanobacteria belonging to Girvanella Group,and they are of lamina and irregular meshwork structure respectively.It is suggested that these oncoids were formed by the sophisticated calcification and early lithification of spherical microbial mats or microbial films in high-energy oxygenated environment.Huludao oncoids provides a typical example for studying the mechanism of the carbonate coated particles such as oncoids formed by the interaction between microorganisms and flowing water in high energy water of Early Paleozoic.

关 键 词：核形石 微生物膜 钙化蓝细菌 钙化作用 

分 类 号：TE122.2[石油与天然气工程—油气勘探]