【摘要】 本文报道了位于华北克拉通北缘辽西阜新地区温头营子一种特殊的岩石类型——“锂云母岩”，通过野外地质、岩相学、年代学以及矿物地球化学的系统研究，确认“锂云母岩”产于伟晶岩的内部分带，并对伟晶岩的时代和类型进行约束，探讨“锂云母岩”的成因及其成矿意义。独居石U-Pb(233±4Ma、231±3Ma)和云母Rb-Sr(227±4Ma)定年结果表明温头营子伟晶岩的成岩成矿时代为三叠纪，形成于古亚洲洋闭合后岩石圈伸展的高热地球动力学环境。成矿伟晶岩发育良好的矿物分带现象，由外及内依次为细粒石英长石边缘带/文象结构带、块状石英长石带、块状锂云母石英长石带和“锂云母岩”核部带。“锂云母岩”分带主要由紫色锂云母组成(>90%)，长石、石英含量极低。云母地球化学组成与赋矿围岩特征反映温头营子伟晶岩属于高分异成因的LCT型伟晶岩，其内部分带结构以及“锂云母岩”的形成不仅受到带状纯化过程的主导控制，也经历了岩浆分异晚期出溶流体的影响。温头营子三叠纪“锂云母岩”的发现反映中国东北地区也具有优质锂矿的成矿条件与探矿潜力。中亚造山带东段与西段的锂矿床可能共同构成一条中国北方印支期伟晶岩型锂成矿带，值得后续进一步关注与研究。更多还原

【Abstract】 This paper presents a special rock type,the “lepidolite rocks,located in Wentouyingzi,Fuxin area of western Liaoning on the northern margin of the North China Craton. Through a systematic study of field geology,petrography,geochronology and mineral geochemistry,it is confirmed that the “lepidolite rocks” occur in the internal zones of pegmatites. Furthermore,this study constrains the type and age of the Wentouyingzi pegmatites,and also discusses the genesis and metallogenic significance of the “lepidolite rock ”.The monazite U-Pb( 233 ± 4 Ma and 231 ± 3 Ma) and mica Rb-Sr( 227 ± 4 Ma) ages indicate that the Wentouyingzi pegmatites were formed in the Triassic under a high-temperature geodynamic environment of lithospheric extension after the closure of the Paleo-Asian Ocean. The metallogenic pegmatites at Wentouyingzi display a well-developed mineral zoning,from outside to inside,including finegrained quartz-feldspar marginal zone/graphic zone, massive quartz-feldspar zone, massive lepidolite quartz-feldspar zone and“lepidolite rock” core zone. The “lepidolite rock” zone is mainly composed of purple lepidolite( > 90%),with extremely low contents of feldspar and quartz. The geochemical compositions of micas and the characteristics of the surrounding rocks indicate that the Wentouyingzi pegmatites belong to the LCT-type pegmatites of highly differentiated origin,of which the well-developed zonation and the formation of “lepidolite rocks” were not only controlled by the constitutional zone refining process,but also influenced by the exsolved fluids during the late differentiation of magma. The discovery of the Triassic Wentouyingzi “lepidolite rock” reflects that Northeast China also has favorable conditions and exploration potential for high-quality lithium deposits. Lithium deposits in both the eastern and western segments of the Central Asian Orogenic Belt may form an Indosinian pegmatite-type lithium mineralization belt in northern China,which is worthy of further attention and research.更多还原