Hydrothermal origin of elevated iron,manganese and redox-sensitive trace elements in the c.635 Ma Doushantuo cap carbonate

作     者：JING HUANG~(1,2),XUELEI CHU~(1,2*),GANQING JIANG~3,LIANJUN FENG~1 & HUAJIN CHANG~4 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 State Key Laboratory of Lithospheric Evolution,Beijing 100029,China 3 Department of Geoscience,University of Nevada,Las Vegas,NV 89154-4010,USA 4 School of Life and Geography Sciences,Qinghai Normal University,Key Laboratory of Tibetan Plateau Environment and Resources,Ministry of Education,Xining 810008,China 

会议名称：《中国科学院地质与地球物理研究所第11届（2011年度）学术年会》

会议日期：2012年

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：funded by the Ministry of Science and Technology of China(Grant 201 1CB808805) the Natural Science Foundation of China(Grants 40532012,40873007,40603021) The US National Science Foundation provided support to G.Q.J(EAR-0745825) 

摘      要：Major and trace element,including REE,concentrations of the Doushantuo cap carbonate(c. 635 Ma) in South China show enrichment in Fe,Mn and redox-sensitive elements and slightly negative Ce anomalies,indicating anoxic environments during cap carbonate *** Fe/Al ratios but very low concentration of extractable pyrites suggest ferruginous rather than euxinic *** REE + Y patterns of samples show enrichment of heavy REE(HREE),positive Eu anomalies and positive Y anomalies,implying a hydrothermal origin for elevated concentration of Fe,Mn and redox-sensitive *** results suggest that ferruginous Ediacaran oceans may have rooted from hydrothermally induced iron accumulation in severely glaciated Cryogenian oceans.