沉积型铝土矿鲕豆粒结构特征及其成因分析  

Texture Characteristics and Genesis of Bean-pebble of Sedimentary Bauxite Deposits

作　　者：胡旭[1] 伊海生[1] 王刚[2] 欧莉华[1] 

机构地区：[1]成都理工大学沉积地质研究院,成都610059 [2]成都理工大学地球科学学院,成都610059

出　　处：《重庆科技学院学报（自然科学版）》2013年第2期5-9,共5页Journal of Chongqing University of Science and Technology：Natural Sciences Edition

基　　金：中国地质调查局项目(1212011085415;2011BAB04B10)

摘　　要：在系统研究国内典型沉积型铝土矿矿石物质成分及显微结构特征的基础上,讨论沉积型铝土矿的鲕豆粒结构特征,并分析其成因机制。研究表明:沉积型铝土矿物质成分单一,杂质含量较少,主要为一水硬铝石;鲕豆粒的类型复杂多样,可观察到豆粒和鲕粒,鲕粒包含类型有真鲕、表鲕、复鲕等;鲕豆粒核心变化较大,外部同心圈层断续环绕核心分布。铝土矿中鲕豆粒最初由胶体凝聚形成,但一般后期都经历了搬运活动,表现为异地沉积的特点。Taking two typical depositional bauxites in China as examples,based on the substances and microstructure characteristics of bauxite ore,this paper discusses the bean-pebble texture in details and analyzes its origin mechanism.The research results show that the depositional bauxite contain simple composition and less impurity,mainly diaspore.The types of bean-pebble gains are complicated and various,including posolite and oolite,and the former one further contains compound oolites and superficial oolites.The cores of bean-pebble gains differ enormously in size,while the outer concentric layers distribute surrounding the core interruptedly.The bean-pebble gains are inferred to be formed of condensed colloform and transported in later periods,which can be proved by allogene deposits.

关 键 词：沉积型铝土矿 鲕豆粒 显微结构特征 成因机制 

分 类 号：P618[天文地球—矿床学]