摘要
通过分析四川容须卡伟晶岩型锂多金属矿床中酸性侵入岩和伟晶岩的地球化学特征,探讨其成矿地层、构造及岩浆岩等成矿地质条件。该矿床中酸性侵入岩为钙碱性准铝质岩石,属于Ⅰ型花岗岩系列,伟晶岩属钙碱性强过铝质岩石,二者的稀土和微量元素地球化学特征差异明显。中酸性侵入岩形成于后碰撞构造环境,与松潘—甘孜造山带碰撞造山作用有关,其物质来源可能为地壳物质的部分熔融,同时有少量幔源物质加入,伟晶岩与中酸性侵入岩可能为同源岩浆分异演化的产物。区域性推覆造山运动形成的褶皱、断层及穹隆,为含矿热液的充填和成矿元素的富集提供了有利空间。富含挥发分及稀有金属的熔体侵位于围岩,渗透率较小的泥质岩限制了热量的扩散及成矿有利物质的流失,熔体缓慢固结,形成含矿伟晶岩。
Through the analysis on the geochemical characteristics of the intermediate acid-acid intrusive rocks and pegmatites in the pegmatite type lithium polymetallic ore deposit in Rongxuka of Sichuan Province,the authors discussed the metallogenic geological conditions of stratigraphy,tectonics and magmatites.The results show that the intermediate acid-acid intrusive rocks in Rongxuka area are calc-alkaline and quasi-aluminum rocks,and belong to the I-type granite series.The pegmatites are calc-alkaline and strongly peraluminous rocks,and there are significant geochemical differences in rare earth and trace elements between the intermediate acid-acid intrusive rocks and pegmatites.The intermediate acid-acid intrusive rocks were formed in post-collision tectonic setting,which might be related to the collisional orogeny of the Songpan-Ganzi orogenic belt.The material source might be partial melting of crustal material mixed with a small amount of mantle composition.Pegmatites and intermediate acid-acid intrusive rocks may be products of differentiation and evolution of homogenous magma.The folds,faults and domes formed by the regional napping provided a favorable space for the filling of ore-bearing hydrothermal fluids and enrichment of ore-forming elements.The melts enriched by volatile and rare metals intruded into wall rocks,and the low-permeability mudstones limited the loss of heat and materials favorable for ore accumulation.Then the ore-containing melts solidified and the rare metal pegmatite veins formed.
作者
徐云峰
秦宇龙
王显锋
李名则
周雄
詹涵钰
武文辉
XU Yunfeng;QIN Yulong;WANG Xianfeng;LI Mingze;ZHOU Xiong;ZHAN Hanyu;WU Wenhui(Key Laboratory for Strategic Resources Evaluation and Utilization of Rare Metals and Rare Earth,Chengdu 610081,China;Sichuan Geological Survey,Chengdu 610081,China;Institute of Multiple Utilization of Mineral Resources,Chinese Academy of Geological Sciences,Chengdu 610041,China)
出处
《中国地质调查》
2019年第1期34-40,共7页
Geological Survey of China
基金
中国地质调查局"四川康定-道孚-雅江稀有金属整装勘查区矿产调查与找矿预测(编号:121201004000150017-93)"
"四川康定瓦多-龙古地区1:5万区域地质调查(编号:DD20160074-02)"
"四川道孚县惠远寺幅1:5万水系沉积物测量(编号:DD20160074-07)"
四川省科技厅"川西锂矿大型能源资源基地成矿关键技术研究与示范(编号:2018SZ0276)"项目联合资助
关键词
容须卡
伟晶岩
锂多金属矿床
地球化学特征
成矿地质条件
Rongxuka
pegmatite
lithium polymetallic ore deposit
geochemical characteristics
metallogenic geological conditions
