湖南雪峰弧形构造带字溪金矿床成因及找矿标志

Genesis and Prospecting Criteria of Zixi Gold Deposit in Xuefeng Arc Structure Belt of Hunan Province

【目的】字溪金矿是湖南雪峰弧形构造带近年来新发现的产于蚀变岩脉中岩的金矿床,探讨其矿床成因,总结找矿标志,对于区内金矿找矿工作有重要指导意义。【方法】通过总结前人的研究成果,综合野外地质特征、岩石地球化学特征观察等方式,探讨了矿床成因,总结了找矿标志。【结果】研究结果表明,区内中基性岩脉岩石类型主要为辉长-闪长岩,其成因与板内大陆裂谷构造环境有密切关系,属于碰撞后伸展活动的产物。矿床形成于雪峰山陆内造山过程中,成矿物质可能主要来源于变质基底。断裂构造、基性岩脉及毒砂化等热液蚀变等是寻找该类型金矿床的重要标志。【结论】研究成果可为区内寻找同类型金矿床提供参考。

[Purposes]Zixi gold deposit is a newly discovered gold deposit in Xuefeng arc structure belt,Hunan province,which occurs in the altered dikes in recent years.[Methods]By summarizing the previ-ous research results,and combing the field geological characteristics and rock geochemical characteris-tics,the deposit genesis is discussed and the prospecting criteria are summarized.[Findings]The results show that the intermediate-basic magmatic rocks in the area are mainly gabbro-diorite,which is closely related to the tectonic environment of intraplate continental rift and belongs to the product of post-collision extension.The deposit was formed in the intracontinental orogenic process of the Xuefeng Mountain,and the ore-forming materials may be mainly derived from the metamorphic basement.Fault structure,basic dike and arsenopyrite hydrothermal alteration are important marks for prospecting this type of gold deposit.[Conclusions]The research results can provide reference for the search of the same type of gold deposits in the region.