摘要
寒武纪早期海洋氧化还原状态的变化经常被用来解释早期动物的辐射和灭绝,但该机制目前并不十分清晰.对华南盆地相渣拉沟剖面开展了总有机碳含量、铁组分、主量元素和微量元素的研究.在此基础之上,将渣拉沟剖面的海水氧化还原状态与华南和西伯利亚其他剖面已发表的研究结果进行了综合对比分析.结果表明,寒武纪第二期至第三期出现了氧化水体的扩张,而寒武纪第四期海洋变得更加缺氧.寒武纪早期海洋氧化还原状态与化石记录之间的对比研究表明,寒武纪第三期海洋氧化程度的增加可能是早期动物辐射的关键因素,而寒武纪第四期海洋缺氧程度的加剧可能是早期动物多样性降低和古杯动物灭绝的直接原因.
Marine redox variations have been frequently used to explain the radiation and extinction of early animals during the Early Cambrian.However,this hypothesis remains unclear.Here,it conducted total organic carbon,iron speciation,major elements,and trace elements in the basinal Zhalagou Section.The new redox results were compared with published redox environments from the coeval other sections in South China and Siberian.The results suggest that oxic waters were intensively expanded during Cambrian Age 2-3,whereas the degree of oceanic anoxia was enhanced during Cambrian Age 4.Comparison of ocean redox states and fossils suggests that enhanced ocean oxygenation might play key roles in the radiation of early animals during Cambrian Age 2-3,but expanded ocean anoxia might have significant effects on the decreased diversification of early animals and extinction of archaeocyaths during Cambrian Age 4.
作者
金承胜
崔豪
程猛
张子虎
常华进
张弢
曹正琦
Jin Chengsheng;Cui Hao;Cheng Meng;Zhang Zihu;Chang Huajin;Zhang Tao;Cao Zhengqi(College of Resource Environment and Tourism,Hubei University of Arts and Science,Xiangyang 441053,China;Changjiang River Scientific Research Institute of Changjiang Water Resources Commission,Wuhan 430010,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2024年第10期3674-3684,共11页
Earth Science
基金
国家自然科学基金项目(Nos.41702129,42002027)
云南省应用基础研究面上项目(No.2019FB143)
湖北文理学院科研启动项目(No.2059163)。
关键词
铁组分
微量元素
缺氧
动物灭绝
扬子陆块
地球化学
iron speciation
trace element
anoxia
animal extinction
Yangtze Block
geochemistry
