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李坝金矿床位于中川印支 -燕山期复式花岗岩体外热变质带即黑云母变质带中 ,带内分布有较多的同类型金矿床 (点 ) ,是礼岷金矿带东部最大的金矿床。矿体产出严格受断裂破碎带控制 ,矿体主要为脉状、透镜状 ,分支复合 ,膨大缩小明显。容矿岩石主要为粉砂质板岩 ,矿石类型简单 ,主要为块状、碎裂状少硫化物浸染型 ,次为角砾状硫化物浸染型 ,矿化组合为金银系列矿物 -黄铁矿 - (毒砂 )。金矿化富集与中酸性岩脉空间密切伴生 ,同位产出。成矿作用可划分为两期四阶段 ,成矿物理化学环境为浅成中低温偏酸性还原富硫环境 (1～ 2 km、t为 188～ 2 56℃、p H为 3.6～ 5.6、lg f O2 为 - 38.8～ - 4 1、lg f S2 为 - 14.8～ - 16 )。地质、同位素地球化学综合研究认为矿床成因为岩浆 -变质混合成矿流体浅成中低温充填 -交代矿床。
The Liba gold deposit is located in the exothermal metamorphic belt of the Indosinian-Yanshanian granite, ie, the biotite metamorphic belt. There are many gold deposits (spots) of the same type in the belt, which is the largest gold deposit in the eastern part of the Li-Ming gold belt . The ore body output is strictly controlled by the fracture and fracture zone. The ore bodies are mainly vein-shaped, lens-shaped and branch-complexed, and the enlargement and shrinkage are obvious. The ore-hosting rocks are mainly silty slate. The types of ore are simple, mainly of massive and disintegrating minor sulphide dipping type, followed by brecciated sulphide dipping type. The mineralization combination is a series of gold and silver minerals - pyrite Mine - (arsenopyrite). Gold mineralization enrichment and intermediate acid dyke space closely associated with the same output. The mineralization can be divided into two phases and four stages. The physico-chemical environment of the ore-forming is as follows: Sulfur content is slightly reduced to moderate and low temperature (1 ~ 2 km, t is 188 ~ 2 56 ℃, p H is 3.6 ~ 5.6, lg f O2 For - 38.8 ~ - 4 1, lg f S2 for - 14.8 ~ - 16). Geological and isotopic geochemistry comprehensive study suggests that the ore deposit is formed by the magmatic-metamorphic mixed ore-forming fluids, which are shallow, medium and low temperature filling-metasomatic deposits.