该文以老君山锡多金属成矿区为研究对象,根据与成矿相关的地质作用的组合特征(加里东期火山喷流沉积成矿作用、印支期区域变质作用和燕山期花岗岩叠加改造成矿作用),厘定了三大成矿系列。通过不同成矿系列矿床的稀土元素地球化学对比研究,发现各成矿系列矿床的稀土元素配分模式具有明显区别如下:Ⅰ.加里东期海底火山喷流沉积一印支期变质成矿系列,分布于老君山花岗岩体的北东部外围,其稀土元素配分模式与海相火山喷流沉积岩(岛弧拉斑玄武岩)类似;Ⅱ.加里东期海底火山喷流沉积一印支期变质一燕山期花岗岩热液叠加改造成矿系列,分布于老君山花岗岩接触带附近,具海底火山喷流沉积岩和花岗岩并存的稀土元素配分模式;Ⅲ.燕山期花岗岩热液成矿系列,位于老君山花岗岩体及接触带,其稀+元素配分模式与地高萤熔刭花岗岩一致。
This paper focuses on the Laojunshan tin poly-metallic metallogenic region and studies the geological processes related to ore forming processes such as volcaniclastic sedimentation in early Caledonian, region_al metamorphism in Indo-China period, superimposed late Yanshanian granitic process magmatism. Three types of metallogenieI series were recognized, and each kind of metallogenic series has different REE distribution patterns. Type Ⅰ. Volcaniclastic sedimentation in early Caledonian-regional metamorphism in Indo-China period metallogenic series in the northeastern part of the study area have the similar REE distribution patterns with marine extrusive-sedimentation rocks (island-arc tholeiite type). Type Ⅱ Volcaniclastic sedimentation in early Caledonian-regional metamorphism in Indo-Chinese epoch metallogenic series, near the granite contact zones, the REE distribution patterns show the coexistence of marine extrusive-sedimentation rocks and granites. Type Ⅲ. Superimposed granitic metallogenicseries of the late Yanshanian epoch have the similar REE distribution patterns with those of granites.