Study on the Metallogenesis during the Early Stage of Continental Collision in Southern Gangdese, Tibet
详细信息
- 责任者：Huang Wenting (Key Laboratory of Mineralogy and Metallogeny ; Guangzhou Institute of Geochemistry ; Chinese Academy of Sciences ; Guangzhou 510640 ; China) ; Liang Huaying
- 刊名：Acta Petrologica Sinica
- 出版年：2013
- 卷期：29(4)
- 关键词：多金属矿 ; polymetallic ores ; 成矿作用 ; metallogenesis ; 冈底斯山 ; Gangdise Range
- 页码：p.1439-1449
- 图表：illus., 4 tables, 72 refs.
- 分类号：1001
- issnNo：ISSN1000-0569
- isbnNo：CN11-1922/P
摘要
Many porphyry Cu-Mo and Cu-Pb-Zn polymetal deposits have been found in the southern Gangdese belt, forming a porphyry copper ore belt and a polymetal ore belt, respectively. Previous geochronologic results indicate that most deposits in the southern Gangdese belt were formed after 30Ma and in post-collisional extension evnironment. In this paper, we analyze zircon U-Pb age of igneous rocks closely associate with the Jialong skarn Fe deposit and the Sadang Au-Ag deposit, respectively, and molybdenite Re-Os age of the Duodigou skarn Mo deposit in the southern Gangdese. The Jialong biotite monzonite granite closely associated with skarn Fe deposit has zircon LA-ICP-MS U-Pb age of 61.1±0.4Ma with MSWD=0.94. The Sadang andesite closely associated with Au-Ag mineralization has zircon LA-ICP-MS U-Pb age of 62.6±0.5Ma with MSWD=1.51. The molybdenite Re-Os model ages of the Duodigou skan Mo deposit varies from 64.3±0.8Ma to 69.2±3.3Ma, with an average weight age of 66.7±6.4Ma, MSWD=8.1. Our new results suggest that the three deposits own their origin to the magmatic events triggered by early Indus-Eurasia collision. Our results, together with former work, reveal that the southern Gangdese has undergone large-scale mineralization associated with the strong magmatic activities during the early Indus-Eurasia collision. It is, therefore, suggested that the southern Gangdese could be an important target area for mineralization related to early Indus-Eurasia collision.