九江网纹红土中粘土矿物过渡相的矿物学特征及成因  

Mineralogy and Genesis of Mixed-Layer Clay Minerals in the Jiujiang Net-Like Red Soil

作　　者：殷科[1] 洪汉烈[1] 李荣彪[1,2] 韩文[1] 吴钰[3] 高文鹏[1] 贾锦生[1,4] 

机构地区：[1]中国地质大学(武汉)地球科学学院,湖北武汉430074 [2]凯里学院旅游学院,贵州凯里556000 [3]中国地质大学(武汉)珠宝学院,湖北武汉430074 [4]浙江省第三地质大队,浙江金华321001

出　　处：《光谱学与光谱分析》2012年第10期2765-2769,共5页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(41072030;40872038);教育部高等学校博士学科点专项科研基金项目(20110145110001)资助

摘　　要：为研究长江中下游网纹红土中粘土矿物过渡相的矿物学特征及成因,采用X射线衍射(XRD)、傅里叶红外吸收光谱(FTIR)、以及高分辨透射电子显微分析(HRTEM)等现代测试技术方法,对江西九江红土剖面网纹红土中粘土矿物过渡相开展系统、深入的研究。X射线衍射及红外吸收光谱分析结果表明,九江剖面网纹红土中粘土矿物组成主要有伊利石和高岭石,少量蒙脱石和伊利石/蒙脱石及微量高岭石/蒙脱石混层矿物过渡相。在高分辨透射电子显微镜下,可观察到蒙脱石晶层向高岭石晶层转化的现象。伊利石/蒙脱石过渡相是伊利石向蒙脱石转化的过渡产物,而高岭石/蒙脱石过渡相则为蒙脱石向高岭石转化的过渡产物,网纹红土中这两种过渡相的出现说明了粘土矿物风化演化的过程,即:伊利石→伊利石/蒙脱石混层矿物→蒙脱石→高岭石/蒙脱石混层矿物→高岭石的演化,同时表明网纹红土形成于风化作用增强的温暖潮湿气候环境。Mineralogy and genesis were investigated using X-ray diffraction （XRD）, Fourier infrared absorption spectroscopy （FTIR） and high resolution transmission electron microscopy （HRTEM） to understand the mineralogy and its genesis significance of mixed-layer clay minerals in Jiujiang red soil section. XRD and FTIR results show that the net-like red soil sediments are composed of illite, kaolinite, minor smectite and mixed-layer illite-smectite and minor mixed-layer kaolinite-smectite. HRTEM observation indicates that some smectite layers have transformed into kaolinite layers in net-like red soil. Mixed-layer illite-smectite is a transition phase of illite transforming into smectite, and mixed-layer kaolinite-smectite is a transitional product relative to kaolinite and smectite. The occurrence of two mixed-layer clay species suggests that the weathering sequence of clay minerals in net-like red soil traversed from illite to mixed-layer illite-smectite to smectite to mixed-layer kaolinite-smectite to kaolinite, which indicates that net-like red soil formed under a warm and humid climate with strengthening of weathering.

关 键 词：网纹红土 九江 早中更新世 粘土矿物过渡相 矿物学特征及成因 

分 类 号：P571[天文地球—矿物学]