闽北中生代火山岩浆活动与金属成矿的关系

THE RELATIONSHIP BETWEEN MESOZOIC VOLCANIC MAGMATIEM AND METAL MINERALIZATION IN NORTHERN FUJIAN

Based on the study of petrology and geochemistry, the author approached the relationship between Mesozoic volcanic magmatism and metal mineralization by analysing some typical districts, and suggested that two different epochs of ore-forming series corresponding to the two stages of plate movement respectively be developed. The former is more important, with relation to Late Jurassic volcanic magmatism taking place in compressional environment. And its source of ore materials has ambiguity (coming from itself and/or host rocks). This series include mineralization with relation to intermediate acidic rocks (epithermal Au-Ag and Ag-Au base metal, Au-Ag quartz vein, and Au-Ag Au Pb Zn sulfide vein type), and Au-Cu mineralization related to nearly intermediate rocks and having closely spatial association with porphyry bodies and breccia pipes. The latter developed in relatively deep sites along the margin of Early Cretaceous volcanic basins, with relation to Early Cretaceous magmatism in compressional-extensional nvironment. And the ore-forming metal depends on the orebearing characteristics of wall rocks. Cu and Pb-Zn mineralizations are the main components of this series.