中俄阿尔泰山中生代花岗岩与稀有金属矿床的初步对比分析  

A preliminary comparison of Mesozoic granitoids and rare metal deposits in Chinese and Russian Altai Mountains.

作　　者：韩宝福[1] 

机构地区：[1]造山带与地壳演化教育部重点实验室,北京大学地球与空间科学学院,北京100871

出　　处：《岩石学报》2008年第4期655-660,共6页Acta Petrologica Sinica

基　　金：国家重点基础研究规划项目(编号:2007CB411305、2001CB409802);国家科技支撑计划重点项目(编号:2006BAB07B08);中国地质调查局项目(编号:1212010611803)资助

摘　　要：中国阿尔泰山和俄罗斯阿尔泰山均属于阿尔泰山脉的组成部分,地理上互相连接,地质上具有相似的古生代演化历史,同样都发育中生代花岗岩及伴生的稀有金属矿床。中国阿尔泰山和俄罗斯阿尔泰山的中生代花岗岩及其稀有金属矿床既表现出一定的相似性,也存在一定的差别。两地与稀有金属矿床有关的中生代花岗岩主要为S型花岗岩,属于非造山花岗岩类,但在俄罗斯阿尔泰山发育以岩珠和岩脉型钨-钼、锂-钽为主的稀有金属矿床,时限为晚三叠世和早侏罗世,而中国阿尔泰山则发育以花岗伟晶岩脉型锂-铍-铌-钽为主的稀有金属矿床,时限从晚三叠世到晚侏罗世。这些花岗岩具有相似的Sr- Nd同位素特征,但^(87)Sr/^(86)Sr初始比值变化很大,可能是岩浆-流体作用的结果,而变化较小的ε_(Nd)(t)值与富集地幔来源的岩浆基本相当,或者可以解释为幔源岩浆与地壳物质混合的结果。Chinese and Russian Altai Mountains are component parts of the Ahai Mountains in Central Asia, and both show similar geological evolution during the Paleozoic and are characterized by Mesozoic granitoids and related rare metal deposits. However, a preliminary comparison shows some similarities and differences in these granitoids and related rare metal deposits between the two parts of the Ahai Mountains. In Chinese and Russian Altai Mountains, the Mesozoic granitoids are composed of granite-leucogranite associations （mainly S-type） , belonging to anorogenic granitoids, but the rare metal deposits in Russian Ahai Mountains are dominated by W-Mo and Li-Ta ones formed from late Triassic to early Jurassic and closely related to late-stage granitic stocks and dykes, whereas those in Chinese Altai Mountains by Li-Be-Nb-Ta deposits formed from late Triassic through Jurassic and dominantly related to granopegmatitic veins. These granitoids show similar Sr-Nd isotope characteristics, their initial ^87Sr/^86Sr ratios vary greatly possibly as a result of magma-fluid interaction, whereas their εNd （t） values are in a range of enriched mantle represented by lamprophyre. Alternatively, they might have resulted from the mixing of mantle and crustal materials.

关 键 词：阿尔泰山 中生代花岗岩类 非造山 稀有金属矿床 

分 类 号：P588.121[天文地球—岩石学] P618.6[天文地球—地质学]