摘要
铝土矿和其下部的铁质粘土岩组成铝岩系.铝土矿的铝硅和铝铁均呈反比关系,硅铁呈正比关系,这一特征反映出第一期脱硅,第二期脱铁的两期风化成矿作用.粘土岩的铝含量稳定,铁含量变化大,硅铁是反比关系,显示第二期风化作用,脱出的铁质在粘土岩内沉淀,并生成山西式铁矿.铝岩系具有Al_2O_3/SiO_2和Fe_2O_3/SiO_2两值间同步正相关,显示铝土矿及其母质层粘土岩的陆壳风化成矿.
The bauxite deposit and its ferri-clay rocks in lower part make up an aluminum rock system and the aluminum in bauxite deposit shows an inversal proportion relationship with both silicon and iron while silicon coincides with iron in content. This characteristics reflects two phases of weathering mineralization, i.e. desilication in first phase and deferrization in the second The stable aluminum content, variable iron content and inversal proportion between silicon and iron in clay rocks show that during the second phase of weathering process the released iron was deposited in aluminium rock system and the Shanxi type iron deposit was formed. Aluminium rock system is characterized by the synchronous positive correlation between A12O3/ SiO2and Fe2O3/ SiO2values, showing continental crust weathering mineralization process of bauxite and its clay matrix.
出处
《矿产与地质》
1991年第5期344-348,356,共6页
Mineral Resources and Geology
关键词
铝矿床
成矿
成因
杜家沟
粘土岩
Bauxite, Clay rock, Two phases of weathering mineralization
