海南岛抱伦金矿毒砂的成分特征及成矿温度

Composition characteristics and their significances of arsenopyrite from Baolun gold deposit,Hainan Island metal ogenic temperature

为查明抱伦金矿金的赋存状态,在矿相学观察的基础上,开展毒砂成分电子探针微区测试。结果表明:毒砂中金质量分数高达0. 75%,但分布不均。Fe质量分数在30. 5%～36. 2%,As质量分数在39. 8%～48. 0%,S质量分数在16. 3%～22. 6%,As摩尔分数为29. 1%～34. 9%。金与其他元素无明显的相关性,说明晶格内的金对金含量影响甚微,金主要以包体的形式存在于毒砂中。毒砂形成条件为毒砂和磁黄铁矿组合与毒砂和斜方砷铁矿组合的相过渡条件下,成矿温度在350℃左右。该研究证实抱伦金矿属于中-高温热液矿床。

This paper describes electron probe microanalysis of arsenopyrite composition performed based on mineralogical observation so as to determine the occurrence of gold in Baolun gold deposit.The results show that arsenopyrite has the gold content of up to 0.75%,but with uneven distribution;the mass fractions are 30.5%-36.2%,39.8%-48.0%,16.3%-22.6%and 29.1%-34.9%respectively for Fe,As,S and As;and the absence of an obvious correlation between gold and other elements indicates that the gold in the lattice has little influence on gold content,meaning that gold occurs in arsenopyrite mainly as inclusion;arsenopyrite forms at the mineralization temperature of about 350℃during the phase transformation of arsenopyrite and pyrite assemblage and arsenopyrite and lollingite assemblage.The research confirms the Baolun gold deposit belongs to meso-hypothermal deposit.