焦家金矿带基性脉岩与矿化的空间关系及找矿预测

Spatial relationship between mafic dykes and gold mineralization in Jiaojia gold belt and its significance for prospecting prediction

中文关键词:基性岩脉  构造与蚀变  三维地质模型  找矿预测  焦家金矿带

keywords:mafic dykes  structure and hydrothermal alteration  3D geological model  prospecting prediction  Jiaojia gold deposit

中文摘要:胶东地区是中国最大的金矿集区，拥有焦家、新城、三山岛、玲珑等多个大型生产矿山。焦家金矿是胶东地区最重要的金矿床之一，其成矿主要受焦家断裂控制。由于地表覆盖，目前，对焦家断裂向南延伸部分的产状和成矿潜力不明，制约了矿山下一步的找矿勘查。查明焦家断裂南延部分的找矿潜力可为矿山未来发展和资源增储提供支持，也是矿山一直以来关注的热点问题。胶东地区金矿床普遍发育与成矿同期的基性脉岩，基性岩脉与石英脉型金矿床的成因联系已受到越来越多学者的关注。文章通过提取焦家主生产矿区已有勘查资料的构造和蚀变信息，并利用Leapfrog三维隐式建模软件，建立了矿区基性脉岩、构造、蚀变、矿化的三维可视化地质模型。通过矿区构造、蚀变、矿化与基性脉岩的空间关系分析，并结合基性岩脉中蚀变、矿化的发现，文章提出了基性岩脉带上盘之斜交断裂找矿的新思路，并以南吕-欣木勘查区为例进行了验证。在上述找矿模型基础上，结合矿区南部（朱桥地区）新施工的2个深孔（ZK-J1和ZK-J4）中发育的构造和蚀变特征和区域地球物理资料解译，推测矿区主基性岩脉带和焦家断裂向南部仍有延伸，产状没有明显变化，因此在ZK-J1和ZK-J4之间的北部地区，焦家主断裂南沿位置仍有较好的找矿潜力，建议进一步加大勘查力度。

Abstract:The Jiaodong region, which hosts several world class gold deposits, including Jiaojia, Xincheng, Sanshandao, and Linglong mines, is recognized as the largest gold mineralization district in China, with an accumulated resource of contained metal exceeding 5,000 tons. Jiaojia, as one of the most important Au deposits in the region, has a typical structurally controlled minerallizaion. Currently, the southern extension and the mineralization potential of the ore-controlling structure (Jiaojia fault) remain poorly understood due to regolith, which constrains further exploration. Clarifying the mineralization potential of the southern extension of the Jiaojia fault is crucial for supporting the mine’s future development and resource expansion. Gold deposits in the Jiaodong region are generally associated with mafic dykes that formed concurrently with mineralization. The genetic relationship between mafic dykes and quartz vein-type gold deposits has attracted increasing researchers. The paper extracts structural and alteration information from historical exploration data of the main mining area of the Jiaojia deposit and uses Leapfrog Geo 3D implicit modelling software to establish a 3D visualized geological model of the mafic dykes, structures, alterations, and mineralization. Supported by analysis of the spatial relationship between the structures, alterations, mineralization, and mafic dykes within the mining area, and incorporating the findings of alterations and mineralization in the mafic dykes, a new prospecting model relating to oblique faults on the hanging wall of the mafic dykes is proposed, which is verified by the exploration program in the Nanlv-Xinmu area as an example. Based on this prospecting model, and by integrating regional geophysical data and the structural and alteration data obtained from the recently drilled deep holes ZK-J1 and ZK-J4 in the Zhuqiao of the southern mining area, we propose that the main mafic dyke and the Jiaojia fault zone continue to extend southward without significant changes in their occurrence. Consequently, the southern extension segment of the Jiaojia fault, particularly the area between ZK-J1 and ZK-J4 south of the current mining area, retains substantial prospecting potential. Therefore, we continue to advocate for targeted exploration in this area.