文中研究了相山铀矿田的构造、火山沉积及岩浆岩期后热液成矿作用,提出了矿田地质演化及其铀成矿规律等方面的一些新认识。从145 Ma以来,相山铀矿田的地质演化可划分为3个阶段和与之相对应的3套构造(主要为断裂)体系及2期成矿作用:(1)火山盆地和火山机构形成阶段,是铀成矿的奠基阶段;(2)东、西两部分差异抬升剥蚀阶段,形成的断裂走向总体为SN向,相对应的是早期铀成矿阶段;(3)红盆形成阶段,主要形成NE向断裂带,相对应是晚期铀成矿阶段。第2阶段的构造体系叠加改造第1阶段的构造体系而形成早期铀成矿作用。第3阶段的红盆构造体系对前2阶段构造体系的叠加改造而形成晚期铀成矿作用,晚期成矿作用的强度和规模都要超过早期成矿作用。这3套构造体系相交的降压空间,是找矿的有利部位。
On the basis of the studies of ore-field structure, volcanic hydrothermal mineralization and igneous rocks in the Xiangshan uranium ore-field, the paper has proposed some new understanding of the geological evolution and metallogenic regularity in this ore-field. The geological evolution of the Xiangshan uranium orefield can in general be divided into 3 stages and the corresponding 3 structure (mainly fracture) systems and 2 stages of mineralization since 145 Ma. (1)The stage of volcano complex basin and volcanic edifice forming. It is also the stage of foundation of uranium mineralization, (2)The stage of differential elevation-erosion between the two parts of the east and west stage (i. e. the early mineralization stage). The East was relatively stable while the West was uplifting and underwent intense weathering. SN-trending faults were formed in the stage. (3)Red basin formation stage (i. e. the late mineralization stage). NE-trending fault zones were formed in the stage. In Xia_ngshan uranium ore field there were two main metallogenic stages. The early uranium mineralization was mainly formed in where the second stages of structure activity superimposed on the first stage tectonic system. And the late uranium mineralization was mainly controlled by the red basin and basin controlling fault. The intensity and size of the late mineralization were larger than the early mineralization. The ore-bodies were located in depressed spaces of the intersection of these three sets of structural systems, where are favorable for exploration sites.