{"title":"Seawater barium and sulfide removal improved marine habitability for the Cambrian Explosion of early animals","authors":"Wei Wei, Lin-Hui Dong, Shuhai Xiao, Yi- Bo Lin, Lingang Xu, Guang-Yi Wei, Wenzhong Wang, Lan-Lan Tian, Hai-Zhen Wei, Fang Huang","doi":"10.1093/nsr/nwae237","DOIUrl":null,"url":null,"abstract":"An increase in atmospheric pO2 has been proposed as a trigger of the Cambrian Explosion at ∼539–514 Ma, but the mechanistic linkage remains unclear. To gain insights into marine habitability for the Cambrian Explosion, we analyzed excess Ba contents (Baexcess) and isotope compositions (δ138Baexcess) of ∼521-Myr-old metalliferous black shales in South China. The δ138Baexcess values vary within a large range, and show a negative logarithmic correlation with Baexcess, suggesting a major (>99%) drawdown of oceanic Ba inventory via barite precipitation. Spatial variations in Baexcess and δ138Baexcess indicate Ba removal was driven by sulfate availability ultimately derived from the upwelling of deep seawaters. Global oceanic oxygenation across the Ediacaran-Cambrian transition may have increased the sulfate reservoir via oxidation of sulfide and concurrently decreased the Ba reservoir by barite precipitation. The removal of both H2S and Ba that are deleterious to animals could have improved marine habitability for early animals.","PeriodicalId":18842,"journal":{"name":"National Science Review","volume":"30 1","pages":""},"PeriodicalIF":16.3000,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"National Science Review","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.1093/nsr/nwae237","RegionNum":1,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
An increase in atmospheric pO2 has been proposed as a trigger of the Cambrian Explosion at ∼539–514 Ma, but the mechanistic linkage remains unclear. To gain insights into marine habitability for the Cambrian Explosion, we analyzed excess Ba contents (Baexcess) and isotope compositions (δ138Baexcess) of ∼521-Myr-old metalliferous black shales in South China. The δ138Baexcess values vary within a large range, and show a negative logarithmic correlation with Baexcess, suggesting a major (>99%) drawdown of oceanic Ba inventory via barite precipitation. Spatial variations in Baexcess and δ138Baexcess indicate Ba removal was driven by sulfate availability ultimately derived from the upwelling of deep seawaters. Global oceanic oxygenation across the Ediacaran-Cambrian transition may have increased the sulfate reservoir via oxidation of sulfide and concurrently decreased the Ba reservoir by barite precipitation. The removal of both H2S and Ba that are deleterious to animals could have improved marine habitability for early animals.
期刊介绍:
National Science Review (NSR; ISSN abbreviation: Natl. Sci. Rev.) is an English-language peer-reviewed multidisciplinary open-access scientific journal published by Oxford University Press under the auspices of the Chinese Academy of Sciences.According to Journal Citation Reports, its 2021 impact factor was 23.178.
National Science Review publishes both review articles and perspectives as well as original research in the form of brief communications and research articles.