文献类型：期刊文献

英文题名：Origin of Cherts during the Ediacaran-Cambrian Transition in Hunan and Guizhou Provinces, China: Evidences from REE and Ge/Si; [湘黔地区埃迪卡拉纪-寒武纪之交硅质岩的成因探讨-来自稀土元素和Ge/Si比值的证据]

作者：Wei S. Chen Q. Fu Y. Cui T. Liang H. Ge Z. Zhang P. Zhang Y.

机构：[1]School of Resources and Environments, Guizhou University, Guiyang, 550025, China;[2]Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, 050061, China;[3]Guizhou Geological Survey, Guiyang, 550018, China;[4]Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing, 100037, China;[5]College of Resources and Environmental Engineering, Guizhou Institute of Technology, Guiyang, 550003, China;[6]Jiangsu Electric Power Design Institute, Nanjing, 211102, China

第一机构：School of Resources and Environments, Guizhou University, Guiyang, 550025, China

通信机构：School of Resources and Environments, Guizhou University, Guiyang, 550025, China

年份：2018

卷号：54

期号：5

起止页码：1010-1020

外文期刊名：Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis

收录：Scopus(收录号：2-s2.0-85055488880)

语种：英文

外文关键词：Bedded cherts; Ge/Si; Hydrothermal; Liuchapo Formation; Mounded cherts

摘要：Two types of Liuchapo Formation cherts, bedded cherts and mounded cherts, were deposited in Bahuang section of Tongren in Guizhou Province and Ganziping section of Zhangjiajie in Hunan Province. The origin of the cherts was discussed by analyzing the characteristics of major, trace elements and REE compositions and Ge/Si ratios. It was revealed that the content of SiO2 in bedded cherts was range from 96.06% to 99.61%, and the content of SiO2 in mounded cherts was range from 98.62% to 99.56%, averaging 99.13%, and the contents of other chemical components were very low. Thus, two types of cherts are pure cherts. Moreover, the ∑REE of the bedded cherts in Bahuang section is ranged from 20.14 to 248.56 μg/g (averaging 100.62 μg/g), and no obvious abnormality in Eu/Eu* which is ranged from 0.90 to 1.10 (averaging 1.06), and the ratio of Ge/Si is 0.13-0.98 μmol/mol (averaging is 0.50 μmol/mol), indicating that the origin of bedded cherts affected terrigenous input. Whereas, the ∑REE of the mounded cherts in Ganziping district is ranged from 3.75 to 7.24 μg/g (averaging 5.73 μg/g), the ratio of Ce/Ce* is 0.46-0.66 (averaging 0.57) which shows a negative abnormal, Eu/Eu* is ranged from 2.28 to 11.07 (averaging 4.60) which shows a positive abnormal, and Ge/Si ratio is 1.09-1.43 μmol/mol, (averaging 1.25 μmol/mol) all of which reflect a hydrothermal origin of the mounded cherts. Otherwise, the relationship between Al2O3 and ∑REE in the bedded cherts has an excellent correlation, while in the mounded cherts has a poor correlation. It also illustrates that continental substance plays an important role in controlling the formation of bedded cherts, and the mounded cherts is originated from submarine volcanic or hydrothermal activity. The relationship between Al2O3 and Ge/Si also reflect the origin of cherts. Combined with the paleogeographic environment, it can conclude that the mounded cherts were deposited in syngenetic fault at the margin of the basin, originated from submarine hydrothermal activity, while the bedded cherts were deposit in the deep basin, mainly influenced by terrigenous input. What's more, using 1 μmol/mol as the critical value of Ge/Si may provide a new way to trace the material sources of cherts. ? 2018 Peking University.