新疆西准噶尔苏云河钼矿床含矿岩体地球化学和年代学  

Geochemistry and geochronology of ore-bearing granites in Suyunhe Mo deposit,West Junggar, Xinjiang

作　　者：钟世华[1,2] 申萍[1] 潘鸿迪[3] 郑国平[4] 鄢瑜宏 李晶[5] 

机构地区：[1]中国科学院地质与地球物理研究所矿产资源研究重点实验室,北京100029 [2]中国科学院大学,北京100049 [3]长安大学地质科学与资源学院,陕西西安710054 [4]新疆维吾尔自治区地质矿产勘查开发局第一区域地质调查大队,新疆乌鲁木齐830000 [5]河北联合大学,河北唐山063000

出　　处：《矿床地质》2015年第1期39-62,共24页Mineral Deposits

基　　金：中国科学院知识创新工程项目(编号:KJZD-EW-TZ-G07-1);国家自然科学基金项目(编号:U1303293;41390441;41272109);国家科技支撑计划305项目(编号:2011BAB06B01)的联合资助

摘　　要：苏云河钼矿床位于新疆西准噶尔巴尔鲁克山西段,容矿岩石为二长花岗岩和二长花岗斑岩。这些花岗岩具有类似的地球化学特征：富集Rb、Th、U和LREE,相对亏损Ba、P、Ti,属于高钾钙碱性I型花岗岩系列,局部经历过强烈的分离结晶作用。LA-ICPMS锆石U-Pb定年结果显示苏云河钼矿区的成岩年龄为309.3~310.2 Ma,这表明与成矿有关的岩浆活动发生于晚石炭世。黑云母的Ti温度计表明Ⅰ号和Ⅲ号岩体的结晶温度相近,为695~728℃;而Ⅱ号岩体的结晶温度较低,为642~668℃。同时根据角闪石-斜长石压力计获得Ⅰ号和Ⅲ号岩体的结晶压力为（3.0~3.9）×10^8Pa。综合地球化学研究表明,苏云河钼矿区3个岩体均形成于岛弧环境。此外,以苏云河钼矿床为代表的巴尔鲁克山成矿带与哈萨克斯坦境内的巴尔喀什成矿带在岩石地球化学、成岩成矿时代等方面具有许多类似的特点,表明巴尔鲁克山成矿带可能是巴尔喀什成矿带在中国境内的延伸。The Suyunhe Mo deposit, located in western Barluk Mountain of West Junggar Basin, consists of three granitic stocks. These granites share similar geochemical features. They are characterized by high content of Rb, Th, U,LREE, and relatively negative anomalies of Ba, P, Ti, suggesting I-type granites. Data from some samples indicate that the granites have undergone fractional crystallisation. The results of LA-ICPMS zircon U-Pb dating indicate that the magmatism in the Suyunhe Mo deposit occurred in Late Carboniferous（ 309. 3 ~ 310. 2 Ma）, which was related to the Mo mineralization. The biotite Ti thermometry suggests that the crystal temperatures of stock Ⅰ and Ⅲ are704 ~ 739℃, whereas the crystal temperatures of stock Ⅱ（ 659 ~ 681℃） are lower. Meanwhile, the amphiboleplagioclase barometer indicates that the pressures of stock Ⅰ and Ⅲ are（ 3. 0 ~ 3. 9） × 108 Pa. Both mineral chemistry and petrogenesis studies suggest that the three stocks formed in an island-arc setting. In addition, the Barluk metallogenic belt, represented by the Suyunhe Mo deposit, is similar to Balkhash metallogenic belt in geochemistry and geochoronology, suggesting that the Balkhash metallogenic belt probably extends eastward to the Barluk metallogenic belt.

关 键 词：地球化学 I型花岗岩 LA-ICPMS 斑岩型钼矿 苏云河 西准噶尔 

分 类 号：P618.75[天文地球—矿床学]