广西大厂锡多金属矿田成矿物质来源及矿床成因分析

通过对大厂矿田１ 万多件地表岩石地球化学样品测量数据的统计并与区域地层矿化元素丰度值对比，发现了金属矿化元素在矿田范围内的正晕场和负晕场。根据２ 种晕场的分布及成矿元素含量在空间上的变化特征，推断矿床中锡、银主要来自深部岩浆源或基底地层；锌有很大一部分来源于泥盆系及上覆地层中元素的活化；铜、铅、锑等元素一部分来源于泥盆系及上覆地层，一部分来源于深部岩浆源或基底地层。稳定同位素及矿物流体包裹体成份特征显示，锡石－ 硫化物型矿床的形成与泥盆纪海底喷流－ 沉积成矿作用密切相关，并受到后期岩浆热液活动的改造；夕卡岩型矿床及锑钨石英脉型矿床的成因主要与燕山晚期岩浆活动及相应的热液成矿作用有关

SOURCE OF ORE-FORMING MATERIALS AND ORIGIN OF THE DACHANG ORE FIELD, Guangxi

According to the statistics of geochemical data of the Dachang ore field and comparison of them with elementary abundance of regional strata, the positive and negative geochemical haloes were delineated. Based on the distribution of two types of haloes, it is inferred that tin and silver originate from deep magma or basement strata, most of zinc from Devonian and its overlaying strata, Cu, Pb and Sb from strata and deep magma or basement. The stable isotopes indicate that the metallogenesis is related to exhalation-sedimentation of Devonian Sea basins and magmatic hydrothermal reformation. The Dachang ore field is originally related to late Yanshannian magmatism and hydrothermal fluid process.