山东省兖州市翟村铁矿床地质特征及成因探讨

Study on Geological Characteristics and the Origin of Zhaicun Iron Deposit in Yanzhou City of Shandong Province

摘要:

翟村铁矿床位于山东省最大磁异常——济宁磁异常北部，为验证该异常，在该区通过物探、钻探等勘查方法进行地质找矿，圈定了44个矿体，共求得铁矿石（332)+(333）资源量超过10亿t，平均品位TFe31.09%，mFe22.44%，mFe/TFe的平均值为72.18%。该矿体赋存于新太古代济宁群变质岩中，上覆盖层为寒武纪至奥陶纪地层，矿体呈层状、似层状产出，产状与围岩一致。矿石的主要有用组分为Fe，矿石结构为自形—他形晶粒状结构、包含结构、碎斑结构；矿石构造主要为条带状构造、条带—稠密浸染状构造。铁矿的原始沉积或为近岸浅海陆架产物，沉积物中的火山物质较多，条带状硅铁建造是在热水环境中形成的，其成因类型属沉积变质型铁矿。济宁群浅变质岩是寻找该类型铁矿的有利层位，济宁群分布区是寻找该类型铁矿床的首选靶区。

Abstract:

Zhaicun iron deposit is located in north of Jining anomaly——the largest magnetic anomay in Shandong Province. Geophysical prospecting, drilling and other exploration methods have been used to verify the anomaly in this area. 44 ore bodies have been found, and the total resource amount of (332 + 333) iron ore can exceed 1 billion tons. The ore bodies occurred in metamorphic rocks of Archean Jining group. Its covering is CambrianOrdovician strata. Ore bodies occurred as layered and bedded types. Its occurrence is consistent with the surrounding rocks. Main useful components are Fe. Average grade of(332+333) deposit are as follows: TFe is 31.09%, mTe is 22.44%, and the average grade of mFe/Tfe is 72.18%. Structures of the ores are selfshaped grain structure, containment structure and mortar structure; while structures are mainly banded structure, strip—dense disseminated structure. According to analysis and discussion on geological characteristics, source of forming materials and formation mechanism, it is concluded that the origin of the deposits is sedimentary metamorphic iron deposit.