大长沙火山岩盆地铀成矿条件分析

文章分析了盆地的火山活动、火山岩的地球化学特点和铀矿化特征。认为盆地是塌陷式的，岩浆活动分为两个旋迥，并且不同族迥的岩浆来源深度不同。盆地发育有多期次的矿化蚀变，铀源有地幔铀、基底铀及盖层蚀变而迁移出的活化铀。盆地断裂构造发育，有较好的矿质沉淀场所，又处在有利的铀成矿区域背景之下，因此具有较大的铀成矿远景。

ANALYSIS OF URANIUM METALLOGENIC CONDITIONS OF THE DACHANGSHA VOLCANIC BASIN

This paper analyzes geochemical features of volcanic rocks, the volcanic activity and uraniummineralization characteristics of the basin which is regarded to be a volcanic collapse basin. Itsmagmatic activity is divided into two cycles with different depth of magma source. Multiphasemineralization alterations are developed in the basin. The uranium source includes uranium frommantle, uranium from the basement and remobilized uranium transported from the cover by alteration. The basin has well-developed fault structures and favourable precipitation sites for themetallogenic matter. Moreover, the basin is located in a favourable regional background for theuranium metallization. So it is quite promising for the formation of uranium deposit.