Home | Contact Us | Sitemap | 中文 | CAS | Director's Email
 
Location:Home > Papers > Recent Papers
Submarine hydrothermal contribution for the extreme element accumulation during the early Cambrian, South China TEXT SIZE: A A A

Throughout the geological history of the Earth, submarine hydrothermal activity has played an important role in seawater chemistry, biological evolution and enrichment of metals in the Earth crust. However, the prospect of hydrothermal activity for extreme element accumulation during the early Cambrian, a key geological period, in South China has not been well-constrained. This study reports geochemical (e.g. REE and Sr isotope) investigations of a coarse-grained limestone layer and associated calcite veins in Zunyi and Nayong areas, Guizhou Province, to constrain the hydrothermal activity and evaluate the significance of hydrothermal contribution to extreme element accumulation during the early Cambrian, South China. Our results reveal positive Eu anomalies and higher initial Sr-87/Sr-86 ratios (0.7083-0.7150) for carbonate samples than those of early Cambrian seawater, indicating the presence of hydrothermal processes. Combined with constraints from the spatial relationships and coincidence with adjacent mineralization, these hydrothermal processes provide the most probable contribution for polymetallic Ni-Mo-PGE mineralization. Furthermore, there are abundant hydrothermal dolomite and barite-calcite veins in the dolostone of the Dengying Formation, indicating the occurrence of a variety of hydrothermal fluids. Overall, multi-stage hydrothermal pulses with different fluid compositions spanned the Ediacaran-Cambrian transition in South China. In particular, these hydrothermal fluids with positive Eu anomalies and enriched radiogenic Sr, originating from Proterozoic mafic/ultramafic rocks, may have flowed through the underlying Precambrian silicate clastic rocks (e.g., Xiajiang, Banxi and Lengjiaxi Groups) and may have been crucial for the marine environment, biological diversity and extreme element accumulation during the early Cambrian, South China. (C) 2017 Elsevier B.V. All rights reserved.

Publication name

 ORE GEOLOGY REVIEWS, 86 297-308; 10.1016/j.oregeorev.2017.02.030 JUN 2017

Author(s)

 Han, Tao; Fan, Haifeng; Zhu, Xiaoqing; Wen, Hanjie; Zhao, Chenghai; Xiao, Fang

Corresponding author(s) 

 FAN Haifeng 
 fanhaifeng@mail.gyig.ac.cn  
 Chinese Acad Sci, Inst Geochem, State Key Lab Ore Deposit Geochem, Guiyang 550002, Peoples R China. 

View here for the details 

Copyright © 2017 Institute Of Geochemistry, Chinese Academy of Sciences All Rights Reserved.
Address: 99 Lincheng West Road, Guanshanhu District, Guiyang, Guizhou Province 550081, P.R.China
Tel: +86-851-85895239 Fax: +86-851-85895239 Email: web_en@mail.gyig.ac.cn