Ore-Forming Fluid of Yulekenhalasu Cu-Mo Deposit on the Northern Margin of Junggar Basin, Xinjiang
详细信息
- 责任者：Geng Xinxia (Key Laboratory of Metallogeny and Mineral Assessment ; MLR ; Institute of Mineral Resources ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Yang Fuquan
- 刊名：Geological Review
- 出版年：2013
- 卷期：59(2)
- 关键词：铜矿 ; copper ores ; 钼矿 ; molybdenum ores ; 新疆 ; Xinjiang
- 页码：p.235-247
- 图表：illus., 4 tables, 24 refs.
- 分类号：1001
- issnNo：ISSN0371-5736
- isbnNo：CN11-1952/P
摘要
Yulekenhalasu medium porphyry copper—molybdenum deposit, which mainly hosted by the dioritic porphyrite and slightly occurs in volcanic rocks and porphyraceous adamellite of the Beitashan Formation, is an important deposit in the Kalaxiangeer porphyry copper belt on the Northern edge of the Junggar Basin. Cu—Mo mineralization disseminated or as veinlet and the main type of rock alterations are potassic alteration, silicification, sericitization and propylitization. Inclusions in quartz of the main ineralizing stage have five types: pure vapor inclusions, gas inclusions, liquid inclusions, three-phase CO2-type inclusions and two-phase CO2-type inclusions. In the main ineralizing stage, the ore-forming temperature is mainly 140~340℃ and salinity ranges from 3.06% to 4.97% NaCl equiv, the density ranges from0.61g/cm3 to 1.01g / cm3. The gases in fluid inclusions are chiefly composed of H2O and CO2, N2, CH4, C2H6 secondly. The cations in inclusions are dominanted by Na+ and Ca2+、K+、Mg2+ secondly, the anions are SO2-4 and Cl-、F- secondly. Laser Raman spectra of quartz inclusions indicates that gases in fluid inclusions are major of CO2 and H2O(-OH), a few of CH4 and N2. The inclusions system of main ineralizing stage is H2O—NaCl—CO2—CH4(N2)with deep-sourced characteristics. These suggest that the copper deposits are related to the porphyry and occurred in epizonal oxidation environment. Inclusions in calcite of the carbonate stage are mainly liquid inclusions, and gas inclusions in the minority. The carbonate stage have low medium temperature(from 161℃ to 298℃), low salinity (from 4.65% to 7.17%) and low density(0.78~0.95g/cm3), which reflect the ore-forming fluids are the meteoric water mainly.