Geochemical Characteristics of Platinum Group Elements and Trace Elements for Dabaoshan Copper Deposit in Weixi, Yunnan and Its Geological Significances
详细信息
- 责任者：Zhao Yuhao (State Key Laboratory of Continental Tectonics and Dynamics ; Institute of Geology ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Qi Xuexiang
- 刊名：Acta Petrologica Sinica
- 出版年：2013
- 卷期：29(6)
- 关键词：铜矿 ; copper ores ; 云南 ; Yunnan Province
- 页码：p.2171-2183
- 图表：illus., 2 tables, 35 refs.
- 分类号：1001
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
Dabaoshan copperdeposit is a typical epithermal deposit in Xuelongshan metallogenic belt,northwestern part of Ailaoshan-Jinshajiang tectonic zone. The geochemical data of PGE and trace elements for ore and wall-rock show: 1) ∑PGE and δRh are increasing,the ratios of PPGE/IPGE,Pd/Ir,Pt/Ir and δPt are decreasing gradually fromwall-rock to mineralized wall-rock to ore. In primitive mantle normalized PGE pattern,the 0s,Ir,Ru and Pd have the similar evolution features,but Rhwith positive anomalies and Ptwith negative anomalies in the ore are different from that in the wall-rocks. The contents of Cu are positive correlation with δRh and ∑PGE,and negative correlation with δPt.2) ∑REE,LREE/HREE and δCe are decreasing,and the depleted degrees of Eu, Nb,Ta,Sr,Hf and Zr are increasing gradually from wall-rock to mineralized wall-rock to ore. Which shows that the PGE and trace elements in the ore are different from that inwall-rocks. The fact that the vein orebodies,weakly alteration and developed syntectonic magmatic veins,and δ34 S values of sulfides from ore ( located mainly in + 1.3‰～- 5.2‰,and little in - 8.2‰～- 12. 8‰) , shows the ore-forming elementsderived main from the Cenozoic magmatic liquid,and little from thewall-rocks. Both Dabaoshan copperdeposit and the syntectonic magmatic veins are the products of tectonic movement in the uplift period of Xuelongshanductiledeformation zone in Cenozoic. During the ore-bearing fluid formed by magmatic differentiation mixedwith underground fluid,the ore veins along faults were formed for the change of physical and chemical conditions.