内蒙古温都尔各脱铅锌矿矿床地质特征及综合找矿模型

Geological Characteristics and Integrated Prospecting Model of Lead-zinc Deposit in Wenduergetuo in Inner Mongolia

内蒙古温都尔各脱铅锌矿地处沙麦钨成矿带西南端,奥由特铜成矿带北东部,为近几年新发现的矿床,前人研究较少涉及。为深入研究矿区成矿规律,根据区内最新找矿成果,对区内成矿地质背景、地球化学特征、地球物理特征及矿床地质特征进行了综合分析。研究表明:①铅锌矿体在空间上主要受NE向和NW向断裂构造控制,断裂构造为矿液运移、存储提供了必要的通道及场所;②矿体赋存于燕山期二长花岗岩中,二长花岗岩为矿体形成提供了必要的热源及物源;③矿石主要呈鳞片状、粒状变晶结构,细脉状-星散浸染状构造,块状构造,闪锌矿呈不均匀星散浸染状分布;④矿体多呈带状、少数呈透镜状产出,有分支复合及膨大收缩现象出现;⑤区内铅锌矿是由地下热水经溶解、置换、萃取形成含矿热液,随后期岩浆活动进一步活化、迁移、富集,在合适的位置沉淀成矿,该区铅锌矿属于岩浆热液型铅锌矿。在上述分析的基础上,总结出了地质构造、岩浆活动、围岩蚀变、地球化学异常、极化率异常为区内有利的找矿标志,构建了综合找矿模型,并圈定了5处找矿靶区。其中,B1、B2、B4、B5靶区均分布于F1构造带上,首尾相连,成矿地质背景基本一致,实际上属于一个较大规模的靶区,靶区内构造蚀变带全长约6.2 km,已圈出的4条矿体平均真厚度为3.16 m,向下延伸200 m以上,Zn平均品位为1.03%,反映出靶区成矿潜力均较好,值得进一步开展找矿工作。

Wenduergetuo lead-zinc deposit in Inner Mongolia is located in the southwest part of Shamai tungsten metallogenic belt and the northeast part of the Oyute copper metallogenic belt.It is a newly discovered deposit in recent years which has been rarely involved.In order to deeply study the metallogenic regularity of the mining area,based on the newly prospecting results in this area,the metallogenic geological background,geochemical characteristics,geophysical characteristics and geological characteristics of deposits are studied.The results show that:①the lead-zinc orebodies are mainly controlled by the NE-trending and NW-trending fault structures in space,and the necessary channels for the movement and storage for mineral fluids are provided;②The orebodies are hosted Yanshanian adamellite,the adamellite provides the necessary thermal source and material for the formation of orebodies;③the ore is mainly in the form of scaly granular blastic texture,fine vein-star scattered disseminated structure and block structure,the distribution of sphalerite is characterized in a heterogeneous scattered pattern;④the orebodies are mostly distributed with banded shape,and a few are lenticular shape,with the phenomenons of branching and expansion and shrinkage;⑤the lead-zinc orebodies in this area is formed by the dissolution,replacement and extraction of underground hot water to form ore-bearing hydrothermal fluid,the ore-bearing hydrothermal fluid is further activated,removed and enriched by the later magmatic activity,and precipitates into ore at a suitable location.the lead-zinc deposit in this area belongs to the magmatic hydrothermal lead-zinc deposit.Based on the above discussion results,the favorable prospecting indicators are summarized,they are geological structures,magmatic activities,surrounding rock alteration,geochemical anomalies and polarizabilities anomalies,a integrated prospecting model for this area is established and five prospecting target areas are delineated.The B1,B2,B4 and B5 prospecting target areas are distributed on the F1 structural belt,which are connected end to end.The metallogenic geological background of the four areas are basically consistent with each other,and they are actually belongs a target area with large scale.The total length of the structural alteration zone in this target area is about 6.2 km,the average thickness of the four orebodies that have been circled is 3.16 m,extending more than 200 m downward,and the average content of zinc is 1.03%.The prospecting results further indicated that the metallogenic potential in the prospecting target areas is good,and they are worth conducting further prospecting work.