摘要
自1985年在桂西北中三叠统浊积岩中发现微细粒浸染型金矿以来,该区己受到世人所瞩目。本文在简介区域地质背景与矿床地质特征的基础上,侧重于金矿成矿作用分析。通过对成矿的三源(矿源、水源、热源)、构造(导矿、容矿)、物理—化学条件与运移—沉淀机制和成矿过程分析等,得出中三叠统浊积岩系为容矿岩系之一,而非矿源岩,成矿时基底存在区域岩浆热液活动的认识;并指出在求取元素丰度值过程中所剔除异常值性质的判断时,采用了柯氏正态检验法、岩石孔渗性、镜质组反射率与牙形石色变指数等研究方法的成果。还探讨了右江浊积岩盆地与成矿作用之间的关系、产金层位分带性变化原因。
More and more attention has been paid to Northwestern Guangxi since micro- disseminated gold deposit was discovered in the middle Triassic turbidites there in 1985. On the basis of regional geological background and the geological characteristics of gold deposits, the authors place an emphasis on the analysis of gold mineralization such as resource material, water source, thermal source, ore -conducting and -hosting structures, physical - chemical conditions, transportation -deposition mechanism and ore -forming processes, and then come to a conclusion that the middle Triassic turbidite series is one of ore - hosted strata, but not source strata; and that the regional magmatism existed in the basement during mineralization. The authors point out that Ke's normal inspection method, porosity and permeability of sedimentary rock - masses,vitrinite reflectance and conodont colour change index are adopted to pick anomaly values in calculating abundance value of minerogenetic elements, and also discuss the relation between Youjiang turbidite basin and the mineralization, and the cause of zoning change of gold -hosted strata.
关键词
金矿
中三叠统
浊积岩
微细粒浸染型矿床
成矿作用
广西
gold deposits, middle Triassic series,turbidite, micro-disseminated mineral dep osits,mineralization, Guangxi.
