Full-Text Search:
Home|About CNKI|User Service|中文
Add to Favorite Get Latest Update

Geochronology,Fluid Inclusions,Geochemical Characteristics of Dibao Cu(Au) Deposit,Duolong Ore Concentration Area,Xizang(Tibet),and Its Genetic Type

QIAO Donghai;ZHAO Yuanyi;WANG Ao;LI Yubin;GUO Shuo;LI Xiaosai;WANG Song;China University of Geosciences;Institute of Mineral Resources,Chinese Academy of Geological Sciences MRL Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resource;No.5 Geological Party,Tibet Bureau of Geology and Mineral Exploration and Development;  
Duolong ore cluster area,located in the southern Qiangtang terrane,northern Bangong Lake-Nujiang metallogenic belt,is the largest porphyry-epithermal copper(gold)ore cluster area discovered in recent years.Dibao is located in the most southwest edge of the Duolong ore cluster area.Despite its good exploring prospect,research work is still weak.To promote resource exploration and provide theoretical basis for metallogenic regularity,we conducted zircon U-Pb dating,fluid inclusions and geochemistry research.The 206Pb/238 U weighted average age of 111.2±0.4Ma(MSWD=0.67)obtained for ore-bearing porphyry is consistent with the mineralization magmatism time limit of the Duolong ore cluster area.The fluid inclusion analysis of quartz vein indicates that ore-forming fluid temperatures of the main metallogenic period range from 140℃to 382℃,with most focusing around 240℃to 280℃.In the diagenetic stage,salinity of I-type inclusions from quartz phenocryst ranges from 0.2%NaCleqv.to 20.7%NaCleqv.and mineral-bearing inclusions from 33.6%NaCleqv.To 43.9%NaCleqv.In the metallogenic stage,salinity of I-type inclusions from gypsum-free quartz veins is 0.2%NaCleqv.to 20.8%NaCleqv.and salinity of I-type inclusions from pyrite quartz veins is 1.1%NaCleqv.to 11.1%NaCleqv..Salinity of I-type inclusions from gypsum is 0.5%NaCleqv.to 9.3%NaCleqv..Analysis of main elements and trace elements of drilling DNZK6428samples and factor analysis results indicate that F1,F2 and F3represent diagenetic stage and factor principal components are Y-Ho-Er-Tm-Yb-Dy-Lu-Tb-Eu-Gd-Sm-La-Ce-Pr-Nd-SiO_2-Al_2O_3-CaO,F4 and F5stands for copper(gold)mineralization stage,and factor principal components are Sn-Sb-Ba-Fe_2O_3-Sr-|SiO_2|-Ni-Cu-U-In-Cd-Au-Zn.Pyrite has a centralizedδ34 SV-CDT range of-7.8‰to 4.1‰with an average of -4.23‰,indicating sulfur mainly derived from deep magmatic sulfur,close to mantle sulfur.Granular pyrite has Co/Ni ratios of 0.207to 10.775with an average of 4.39,and vein pyrite has Co/Ni ratios of 0.353to 23.155with an average of 3.802,indicating that two types of pyrite was hydrothermal genesis.Mineragraphy and petrography study shows a typical mineral assemblage of alunite and enargite,suggesting that the Dibao Cu(Au)deposit belongs to high-sulfidation epithermal deposit.
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©CNKI All Rights Reserved