摘要
齐河-禹城地区位于山东省西北部,本文在系统分析区内铁矿成矿地质特征及成矿规律的基础上,与邯邢式、莱芜式铁矿进行了系统对比,提出了“禹城式”矽卡岩型铁矿矿床式,并初步构建了其成矿模式。区内发现李屯、郭店、大张3处富铁矿床,控矿岩体以闪长岩为主,围岩地层主要为石炭系—二叠系,少量奥陶系,矿体呈似层状,矿石以粒状结构、块状构造为主。区内“禹城式”铁矿以李屯矿床表现特征最为显著,矿体以接触带外部碎屑岩层间构造为主要赋存位置,主矿体赋存部位缺失灰岩及大理岩化带,以铁质巨量富集、伴生元素较少为显著矿质富集特征。早白垩纪,壳幔混合岩浆沿盆缘深大断裂上侵,混合岩浆上侵过程中富铁质岩浆热液出溶,受上覆碎屑岩地层屏蔽作用,岩浆热液与奥陶纪碳酸盐岩发生了充分的接触交代作用,并可能改造了沉积地层内“山西式”铁矿,促使磁铁矿经历多期叠加富集,在石炭系—二叠系内层间构造等部位富集形成富磁铁矿。
Qihe-Yucheng area is located in the northwest of Shandong province.Based on systematic analysis of ore-forming geological characteristics and ore-forming regularity in this area,comparing with Hanxing type iron deposit and Laiwu type iron deposit,"Yucheng type"iron deposit has been put forward and metallogenic model has been preliminarily set up.Litun,Guodian and Dazhang rich iron deposits have been found in the area,the ore-controlling rock mass is mainly diorite,the surrounding rock strata are mainly Carboniferous-Permian and a little Ordovician.The ore body is stratified,mainly granular structure and massive structure.Litun deposit is the most typical"Yucheng type"iron deposit in the area.Main occurrence location of the ore body is the interlayer structure of clastic rock outside the contact zone.Limestone and marlinization zone are missing in the main orebody occurrence area.Large amount of iron and less associated elements are significant characteristics of mineral enrichment.Early cretaceous,the crust-mantle mixed magma intruded along the deep and large fault at the basin margin.Due to the shielding of the overlying strata,full contact metasomatism occurred between magmatic hydrothermal fluids and Ordovician carbonate rocks,transformed"Shanxi type"iron ore in the sedimentary strata,and"Shanxi type"iron deposit in the sedimentary strata may has been transformed.It has caused the magnetite to experience multi-phase accumulation and enrichment.The magnetite deposits are enriched in the interlayer structures of the Carboniferous-Permian period.
作者
王怀洪
李秀章
沈立军
朱裕振
周明磊
WANG Huaihong;LI Xiuzhang;SHEN Lijun;ZHU Yuzhen;ZHOU Minglei(Shandong Bureau of Coal Geology,Shandong Ji'nan 250104,China;Geological Planning and Exploration Institute of Shandong Coalfield,Shandong Ji'nan 250104,China;Shandong Institute of Geological Surveying,Shandong Ji'nan 250104,China)
出处
《山东国土资源》
2021年第9期26-35,共10页
Shandong Land and Resources
基金
山东省自然科学青年基金,山东禹城李屯富铁矿床超常富集机制研究:磁铁矿微区元素及同位素的证据(ZR2020QD032)
山东省地质勘查项目,山东省禹城市李屯地区铁矿普查(续作)(鲁勘字〔2020〕19号)联合资助。
关键词
矽卡岩
富铁矿
成矿模式
齐河-禹城地区
山东省
Skarn
rich iron deposit
metallogenic model
Qihe-Yucheng area
Shandong province
