摘要
Through the researches on the field geological characteristics,the regional geological evolution,the space-time distribution,the geochemical characteristics,the genesis,the material sources and the metallogenic geodynamic background.This paper synthetically discusses the ore-forming geological characteristics and regional metallogenic tectonic background of the West Yunnan tin ore belt and makes a simple analysis of its prospecting future.The results show that most of the tin deposits in West Yunnan belong to the types of greisen,hydrothermal veins and skarn.One of the strongest associations with tin deposits is the late Yanshanian-early Himalayan high differentiation granite.It is rich in K and Si and poor in Mg,Fe and comes from the deep remelt.Isotopic age determinations show that the granite-associated tin deposits formed during 110~50 Ma B.P.which is approximately same as the time of medium-new Tethys collisions.Considering the tectonic evolution of the "poly-island-ocean and basin system",it can be concluded that the West Yunnan tin deposits and their related granites were formed by the continental collision regimes.