尼木地区似斑状正长花岗岩地球化学特征及铜钼矿化研究

Geochemical characteristics and Cu-Mo mineralization of porphyroid syenite in Nimu area

尼木地区构造—岩浆活动强烈,为深部成矿物质的活化迁移提供了热能和动能,普遍伴随着铜、钼、钨矿化。本文以尼木地区渐新世似斑状正长花岗岩为研究对象,分析其地球化学特征及与铜钼矿化的关系。研究认为:尼木地区似斑状正长花岗岩为,高铝钙碱性岩石,普遍富集大离子亲石元素Th、Ce、Hf等,亏损高场强元素Nb、P、Ti、Cr等;岩浆期后热液是该区域普遍发生铜钼矿化的主要原因。

The strong tectono-magmatic activities in Nimu area provide thermal energy and kinetic energy for the activation and migration of deep ore-forming materials,which are generally accompanied by Cu,Mo and tungsten mineralization.In this paper,Oligocene porphyroid syenite in Nimu area is taken as the research object to analyze its geochemical characteristics and its relationship with Cu-Mo mineralization.The porphyroid syenites in The Nimu area are high aluminum-calc-alkaline rocks,enriched in large ion lithophile elements such as Th,Ce,Hf and depleted in high field strength elements such as Nb,P,Ti,Cr.The post-magmatic hydrothermal solution is the main cause of copper-molybdenum mineralization in this area.