摘要
山西交口县庞家庄铝土矿属于典型的喀斯特型铝土矿,矿体赋存于上石炭统本溪组,其下部为中奥陶统灰岩。矿石以隐晶质结构为主,含少量碎屑结构与鲕粒结构;矿石的结构特征显示一些风化物质经过了一段距离的搬运,并且矿体在晚期遭受了构造变形作用。X射线衍射分析显示铝土矿石中的主要组成矿物为硬水铝石、高岭石、赤铁矿、针铁矿、方解石与少量锐钛矿、伊利石、石英等。全岩分析显示铝土矿石中的主要成分为Al2O3、Fe2O3、SiO2和TiO2;其中Al2O3与Fe2O3具有较好的负相关关系,而与TiO2具有较好的正相关关系。微量元素Zr、Hf、Nb、Ta、W、Th和U在铝土矿矿化过程中不断富集,元素Zr、Hf,Nb、Ta显示较高的相关性。本文在前人研究基础上,运用稳定元素比值(如Zr/H、Nb/Ta)、Eu/Eu*-TiO2/Al2O3图解和稀土元素配分模式等方法探讨矿床成矿物质来源,研究表明矿体下部中奥陶统灰岩为铝土矿的形成提供了主要的物质来源,此外可能还有少量铝硅酸盐岩的混入。
The Pangjlazhuang bauxite deposit in Jiaokou county, Shanxi is a typical karst bauxite deposit. The orebodies occur in the Upper Carboniferous Benxi Formation, which is underlain by Middle Ordovician limestones. The ore is dominated by pelitomorphic textures, with few detrital textures and oldie textures. These textural features suggest that the banxitie soils were transported over a short distance and suffered tectonic deformations in the late stage. X-ray diffraction resuhs show the principal minerals are diaspore, kaolinite, hematite and calcite, accompanied by some minor accessory minerals such as＇ anatase, illite, plagioclase and quartz. Whole rock analysis reveals A12O3 , Fc2O3 , SiO2 and TiO2 are the main components of the bauxite ores. And Al2O3 has a negative relationship with Fe2O3 , but has a positive relationship with TiO2. Trace elements such as Zr, Hf, Nb, Ta, Th and U were enriched during the baaxitization process. Elements of Zr, Hf, Nb and Ta display significant correlation with each other. Studies of immobile elements ratios such as Zr/Hf, Nb/Ta, bivariate plots of Eu/Eu ＊ and TiO2/A1203, and REE patten suggest that Middle Ordovician limestones are the major source of materials for the bauxite formation. And the alumino-silicate rocks may provide some source of materials for the formation of bauxite ores.
出处
《地质与勘探》
CAS
CSCD
北大核心
2011年第4期593-604,共12页
Geology and Exploration
基金
山西省国土资源厅设立项目“山西省典型铝土矿床伴生矿产赋存状态研究”资助
关键词
铝土矿矿物学地球化学
物质来源
交口县
山西
karst bauxite, mineralogy, geochemistry, source of ore-forming materials, Jiao kou county,Shanxi
