山东省东平汶上地区铁矿矿床成因探讨

山东省东平-汶上铁矿成矿带是鲁西重要的成矿带,区内已发现李官集、彭集等多个大中型铁矿床,探明了铁矿石资源量超过12亿t。通过收集东平-汶上地区基础地质调查、区域重磁、矿产勘查、科研成果等资料,分析了区内地层、构造、岩浆岩及区域航磁异常特征、重力异常特征与铁矿床的对应耦合关系,提出了矿床的3个控矿因素:即控矿地层(泰山岩群雁翎关组、山草峪组,地层控矿专属性)、控矿构造(同斜复式背斜构造)、控矿岩浆岩(改造和破坏了铁矿带的完整性),通过对成矿区带样品采集测试,分别从主量元素、稀土元素、微量元素、原岩恢复、变质岩构造背景等方面进行系统分析对比,探讨了该区铁矿床为海相岛弧火山——沉积变质成因。

Study on the Origin of Iron Deposit in Wenshang-Dongping Area in Shandong Province

Wenshang-Dongping iron deposit is an important iron ore belt in Luxi area. Liguanji iron deposit, Pengji iron deposit and other large and medium-sized iron deposits have been found in this area. The already proved reserve of iron ore resource is more than 12 billion tons. Through comprehensive collection of basic geological survey, regional geophysical prospecting, mineral exploration, scientific research and other information in recent years, regional strata, structures, magmatic rocks, regional aeromagnetic anomaly, gravity anomaly characteristics and the relationship between iron ore deposit have been analyzed. Three major ore controlling factors have been put forward, they are ore controlling strata (Yanlingguan formation, Shancaoyu formation in Taishan rock group, ore controlling strata), ore controlling strucutures (homoclinal compound anticline) and ore controlling magmatite (reformed and destroyed the integrity of iron ore belt). Through collecting and testing samples in this area, main elements, rare earth elements, the recovery of the original rocks and tectonic settings of metamorphic rocks have been analyzed systemically and compared, and the origin of iron deposits in this area has been discussed in detail.