Home | Contact Us | Sitemap | 中文 | CAS | Director's Email
 
Location:Home > Papers > Recent Papers
Proterozoic Fe-Cu metallogeny and supercontinental cycles of the southwestern Yangtze Block, southern China and northern Vietnam TEXT SIZE: A A A
The Yangtze Block has a Paleoproterozoic and Archean basement and was traditionally thought to have been cratonized after the Neoproterozoic. Recent studies reveal that the southwestern part is remarkably different from other parts of the block. Major Fe-Cu deposits are present in the southwestern part where they form the Kangdian IOCG metallogenic province in southern China and northern Vietnam. Large Fe-Cu deposits include Lala and Xikuangshan to the north, Yinachang in the center, Dahongshan and Sin Quyen to the south and possibly Shilu to the south-east. These deposits are characterized by an association of Fe-oxides and Cu-sulfides with REE, Mo, Co, Ag, and Au as common by-products.

The ore deposits are hosted in variably metamorphosed, late Paleoproterozoic rocks (similar to 1.65-1.7 Ga) of the Dahongshan, Dongchuan, Hekou, Sin Quyen, and Shilu Groups, although the age of the Shilu Group in Hainan is poorly constrained. Molybdenite separates from the Yinachang and the Lala deposits have Re-Os model ages of 1.66 and similar to 1.0 Ga. These ages suggest that the Fe-Cu deposits formed in multiple mineralization events over an exceptionally broad time range. There was a minor hydrothermal overprint at similar to 1.45 Ga. Biotite, amphibole, and quartz from several deposits have Ar-40/Ar-39 plateau ages ranging from 850 to 780 Ma, but cluster at 830-820 Ma. These Ar-40/Ar-39 ages are considerably younger than the Fe-Cu deposits and are interpreted as the result of thermal resetting of the K-Ar system during the Neoproterozoic, consistent with the extensive Neoproterozoic igneous activity in the Yangtze Block.

The mineralization styles of the 1.66 Ga deposits in the southwestern Yangtze Block are similar to those of contemporaneous IOCG deposits in other blocks within the Columbia supercontinent, including those in the Leichhardt and Calvert Superbasins, the Mount Isa Inlier, Australia, and those in the Khetri copper belt, NW India. Together with similar hosting strata and associated igneous rocks, the occurrence of these deposits leads us to propose that these blocks were adjacent to each other in the reconstructed Columbia supercontinent. Both South China and India remained together during the assembly of the supercontinent Rodinia and have undergone extensive Neoproterozoic magmatism that overprinted the Fe-Cu deposits. (C) 2014 Elsevier B.V. All rights reserved. 
 

Publication name

 EARTH-SCIENCE REVIEWS, 139 59-82; 10.1016/j.earscirev.2014.08.013 DEC 2014

Author(s)

 Zhou, MF; Zhao, XF; Chen, WT; Li, XC; Wang, W; Yan, DP; Qiu, HN

Corresponding author 

 ZHOU Meifu 
 zhoumeifu@hotmail.com
 1. Chinese Acad Sci, Inst Geochem, State Key Lab Ore Deposit Geochem, Guiyang 550002, Peoples R China
 2. Univ Hong Kong, Dept Earth Sci, Hong Kong, Hong Kong, Peoples R China

View here for the details 

Copyright © Institute Of Geochemistry, Chinese Academy of Sciences All Rights Reserved.
Address: 99 West Lincheng 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