湘东北连云山上石地区伟晶岩型稀有金属矿床的发现及意义OA北大核心CSTPCD

The northeast of Hunan Province,located in the northwestern margin of the central part of the Qinzhou-Hangzhou metallogenic zone,has always been an important polymetallic metallogenic area of Au,Cu,Co,Pb and Zn in China.In this"Li-Co ore survey evaluation and target selection in Lianyunshan area of Hunan Province"project,we carried out the 1∶10 000 geological mapping process and found a large number of spodumene veins,whose single sample grade reached 1.78％.In addition,25 pegmatite veins were found,ranging from 1～10 meters in width,extending mainly in N-W and near E-W directions and from several meters to hundreds of meters.More than 20 mineralized spots of pegmatite were identified,including spodumene,niobium-tantalite,beryl and other rare metal minerals.There are obvious gradual zonings between pegmatite dike and surrounding rock,which can be subdivided into migmatite schist zone(Ⅰ),monzonite granite zone(Ⅱ),tourmaline pegmatite zone(Ⅲ)and massive albitite+spodumene zone(Ⅵ).The lithium ore bodies are mostly located in the massive albitite+spodumene zone,accompanied by a large number of giant crystal tourmaline,muscovite,etc.,showing good lithium metallogenic potential.A large number of rare minerals such as niobium-tantalite and beryl are associated,and some of which reach the co-associated grade of lithium ore.The main ore-bearing pegmatite vein of the deposit is near east-west trend,with a length of more than 1 km,a width of several meters to tens of meters,and a thickness of more than 100 meters.The average grade of Li2O is 1.42％,and the predicted reserves are about 2.56×104 t,which can reach medium scale.The discovery of pegmatitic lithium rare metal deposit in Shangshi area has completely changed the distribution pattern of rare metals dominated by Be-Nb-Ta,indicating the great potential of rare metal mineralization in this area,and of great guiding significance for the new round of ore exploration.