闽中太华山金矿区金坂矿段矿化类型及找矿方向探讨

太华山金矿区位于福建中部尤溪-德化-永泰三县的结合部位之"闽中金矿集中区",是该区具有找矿前景的靶区之一。随着太华山金矿区金坂矿段深部找矿勘查较系统的工程投入,发现了该区段深部的含矿斑岩体及其矿化蚀变系统。通过对金坂矿段620 m中段以上的含矿斑岩、矿化类型、蚀变分带特征及斑岩与各类型矿化的关系等进行系统分析,初步认为太华山金坂矿段矿化类型具有浅成低温热液型金银矿的特征,其金银矿(化)体在空间上与流纹斑岩紧密相伴,主要产于流纹斑岩体的内外接触带中,自上而下的矿化类型分为:顶部(微)细粒浸染型、中部石英细脉/网脉型及深部热液角砾/黄铁矿浸染石英脉型等,成矿具有"一体多型"的特点。结合太华山矿区太华山矿段、尤岭隔矿段地质特征的对比分析,提出了该区深部金银矿找矿地质模型,对完善太华山热泉-次火山斑岩成矿系统模型及其指导深部探矿工作具有重要的意义。

Gold mineralization types and prospecting direction of Jinban ore block in Taihuashan gold ore district of central Fujian Province

Located in the Youxi-Dehua-Yongtai border area in central Fujian Province, the Taihuashan gold ore district is one of the most important gold ore concentration areas in Fujian Province, and is also one of the target areas for gold prospecting. In recent years, systematic deep-seated prospecting work for Jinban ore block in the Taihuashan gold ore district was conducted, which led to the discovery of the mineralized porphyry in the deep zone. The authors analyzed systematically the porphyry characteristics, mineralization type characteristics, alteration and mineralization zoning characteristics and the relationship between the porphyry and various types of mineralization. This preliminary study shows that the Jinban ore block is a hydrothermal epithermal type gold and silver ore deposit, with its gold-silver orebodies closely associated with the rhyolitic porphyry. The main mineralization occurs in the enso-and exo-contact zones of the rhyolitic porphyry bodies, and the mineralization types can be divided from top to bottom into the top (micro) fine disseminated type, central quartz veinlets/stockwork type and deep hydrothermal breccia/disseminated pyrite quartz vein type. The mineralization is characterized by "multiple types in one porphyry". Combined with data from the geological features of the Taihuashan and Youlingge ore blocks, the authors constructed a deep gold-silver ore-prospecting geological model and a Taihuashan hot springs and subvolcanic porphyry metallogenic system model. These models can effectively guide the deep prospecting work in this region and hence are of great significance.