• 责任者：Huang Xiaowen (State Key Laboratory of Ore Deposit Geochemistry ; Institute of Geochemistry ; Chinese Academy of Sciences ; Guiyang 550002 ; China) ; Qi Liang
• 刊名：Mineral Deposits
• 出版年：2013
• 卷期：32(6)
• 关键词：铁矿 ; iron ores ; 铜矿 ; copper ores ; 元素地球化学 ; elements geochemistry ; 天山 ; Tianshan Mountains
• 页码：p.1188-1210
• 图表：10 illus., 4 tables, 76 refs.
• 分类号：1001
• issnNo：ISSN0258-7106
• isbnNo：CN11-1965/P

     Located in the south of Hami basin of Xinjiang, the Heifengshan, Shuangfengshan and Shaquanzi （Cu-）Fe deposits are important deposits in the Aqishan-Yamansu belt of eastern Tianshan. Based on trace element and REE geochemistry, this paper deals with the source and nature of the ore-forming fluid and also discusses ore genesis of theses deposits. LA-ICP-MS analyses show that magnetite contains low V, Cr and Ti （68×10-6, 13×10-6 and 237×10-6 on average, respectively）, indicating that magnetite was derived from the hydrothermal process rather than from the magmatic differentiation. The relatively high Cu content in pyrite probably indicates Cu-bearing inclusions in pyrite, whereas low Pb and Zn concentrations in pyrite may indicate the low abundances of Pb2＋ and Zn2＋ in the ore-forming fluids. The Co/Ni ratios of pyrite indicate that these deposits are of volcanic-hydrothermal origin. Pyrite from these deposits is characterized by very low REE content （ΣREE=0.07×10-6~3.02×10-6）. Pyrite from the Heifengshan Fe deposit shows no obvious fractionation between LREE and HREE, whereas pyrite from the Shuangfengshan Fe deposit and Shaquanzi Fe-Cu deposit shows significant LREE enrichment, with （La/Yb）N values being 3.51~13.4 and 2.76~17.2, respectively. The different REE patterns of calcite for these deposits indicate different fluid compositions and mechanisms responsible for the formation of calcite. There are no Ce anomalies for both pyrite and calcite, indicating the high-T formation of these deposits. Pyrite and calcite from the Heifengshan Fe deposit show REE patterns with negative Eu anomalies, whereas those from the Shuangfengshan and Shaquanzi deposits show positive Eu anomalies, indicating that the ore-forming fluids responsible for the Heifengshan Fe deposit were alkaline and those for the Shuangfengshan and Shaquanzi deposits were acid and reductive. Combined with previous studies, the authors hold that these deposits may be of the volcanic hydrothermal infilling/replacement type.