Kaolin deposits at Melthonnakkal and Pallipuram within Trivandrum block, southern India     

M. Nakagawa  M. Santosh  S. Yoshikura  M. Miura  T. Fukuda  A. Harada 《Gondwana Research》2006,9(4):530-538

The kaolin deposits at Melthonnakkal and Pallipuram mines form part of the Warkalli Formation belonging to the Tertiary sequence in southern Kerala and occur at the boundary between the Tertiary sequence and Precambrian granulite facies metapelites (khondalites). The sedimentary clays are composed mainly of kaolinite, quartz and gibbsite. XRD and SEM studies have revealed that kaolinite is well-crystallized variety and the platy crystals are scarcely broken in the sedimentary clays. These sedimentary kaolins are considered to have been formed by intense tropical weathering of the khondalites, and subsequently transported and deposited with high organic input into lakes near the weathering crust over the basement rock. Besides, the surficial parts of the sedimentary deposits are extensively lateritized with the formation of goethite and hematite by Quaternary tropical weathering processes.  相似文献   

茂名高岭石低温煅烧物化性能变化机理     

刘真真  王勤燕  周汉文  曾伟能 《矿产与地质》2005,19(4):436-439

茂名高岭石经547℃低温煅烧后,由结晶度较高的高岭石转变为变高岭石,主要成分为非晶质和部分有序的半晶质,Si-O-Al键断裂生成Si-O和Al-O键,随着结构的变化,其物理化学性质也随之发生变化.文章对煅烧前后高岭石的粒度、白度、粘浓度等进行测试,并分析这几个重要的物理指标在煅烧前后产生变化的机理.  相似文献   

Kaolinitic meniscus bridges as an indicator of early diagenesis in Nubian sandstones, Sinai, Egypt – discussion     

J. MARCELO KETZER  L. FERNANDO DE ROS  NORBERTO DANI 《Sedimentology》2005,52(1):213-217

  相似文献   

Dewatering effects on the erodibility of newly deposited cohesive beds by unidirectional currents     

EDUARDO A. GÓMEZ  CARL L. AMOS† 《Sedimentology》2005,52(1):183-189

A series of laboratory experiments on cohesive sediments under inorganic conditions was undertaken in order to evaluate the impact of fluid bed shear stress on the build-up of bed resistance to erosion with time. The importance of small pressures due to flowing water to increase bed strength is presented. It is also shown that the susceptibility of a cohesive bed to changes in its erodibility is related to deposited bed thickness due to sediment disturbance caused by dewatering from the consolidating bed. Laboratory experiments that use beds deposited from suspension should thus report the thickness of the bed prior to resuspension.  相似文献   

高岭土的化学成分与表面电性研究   总被引：4，自引：0，他引：4  

刘晓文  胡岳华  黄圣生  邱冠周 《矿物学报》2001,21(3):443-447

在前人工作的基础之上 ,研究了高岭土中高岭石的晶体结构、化学成分与表面电性之间的关系。硬质和软质高岭土具有相近的表面零电点 (pzc)值 ,几种硬质高岭土的 pzc值的变化范围为 2 .6～ 3 .8。pzc值与其中的SiO2 的重量百分含量呈正相关 ,与Al2 O3的呈负相关。高岭石的结晶度指数 (CI)并不是决定高岭石pzc值的主要因数。在较宽的pH值范围 ,硬质高岭土比软质高岭土的电位低。在高岭石晶体端面上的等电点 ( pH 7.3± )处 ,高岭土表面的Zeta电位与TFe的重量百分含量呈负相关性 ,与高岭石的结晶度指数 (CI)呈正相关。  相似文献   

高岭石—聚丙烯腈夹层复合物的制备   总被引：8，自引：1，他引：8  

厦华  佟健  侯常娥 《矿物岩石》2001,21(4):7-10

作者通过XRD和IR等手段研究了高岭石－聚丙烯腈夹层复合物的形成过程。通过对高岭石／DMSO（二甲亚砜）、高岭石／乙酸铵等中间复合物的置换反应，成功地将丙烯腈单体引入高岭石层间。XRD谱表明高岭石层间被插入有机分子后，其层间距增大；IR谱显示有机分子与高岭石的外羟基可能以氢键的形式相互作用。在有引发剂的存在下，实现了丙烯腈单体在高岭石层间的聚合。  相似文献   

Copper-bearing clay minerals of the oxidized zone of the Rakha-Chapri Block,Singhbhum Copper Belt,India     

S. G. Tenginkai  A. G. Ugarkar  M. V. Koti  A. Mookherjee 《Journal of Earth System Science》1991,100(1):13-29

In the oxidized zone of Rakha-Chapri Block of the Singhbhum Copper Belt, alteration of biotite, chlorite and muscovite extends down to ∼ 60 m. Below this level, these minerals are not altered, implying a supergene origin for the clay alteration products. The altered host-rock profile consists of an upper, predominantly kaolinitic zone and a lower illite-chlorite rich zone, with the clay minerals showing an overall tendency to decrease with depth. Kaolinite is the dominant clay mineral, the proportion of which varies considerably with depth, and chlorite, illite and halloysite are the other clay minerals of the oxidized zone. Incipient removal of copper even from the cap rocks, in-situ transformation of sulphides to oxidized compounds, and the unusual mode of occurrence of copper in the oxidized zone are the characteristic features of the Rakha-Chapri Block. Insufficient localized hydrolysis of silicates is considered responsible for relatively low acidity in the oxidized zone as a whole. Copper forms a component of the clay minerals probably as surface adsorbed or/lattice-bound ions.  相似文献   

煤矸石粘土工业利用的X射线研究     

吴乾荣 《矿物学报》1989,9(2):187-191

本文利用X射线衍射分析方法对徐州某煤矿的煤矸了进行实验,阐明煤矸石工业利用途径。实验表明:该煤矸石的矿物组分比较简单,主要有高岭石、石英;化学成分以SiO_2(57·26%)、Al_2O_3(20.22%)为主,经高温衍射实验,高岭石的分解温度为560—600℃;莫来石生成的温度为1000—1300℃。经X射线衍射定量,高岭石含量为40%左右,莫来石含量33%左右。  相似文献   

煤系高岭石有机夹层作用的实验研究   总被引：4，自引：0，他引：4  

刘钦甫  丁述理  宋丽君  朱在兴 《岩石矿物学杂志》1996,15(2):153-157

本文利用ＸＲＤ和ＩＲ研究了丙烯酰胺和脂肪酸盐与煤系高岭石的夹层作用及稳定性。通过极性有机化合物作夹带剂，成功地合成了高岭石－丙烯酰胺、高岭石－脂肪酸盐有机复合体。夹层作用完成后，层面间距从７．１８Ａ分别扩大到１１．２２Ａ和１１．３２Ａ。有机化合物能在高岭石层间形成稳定的夹层主要与夹层分子和高岭石内表面羟基形成氢键有关。  相似文献   

高岭石形成赛隆过程相变初探   总被引：5，自引：0，他引：5  

邱克辉  张其春 《矿物学报》1996,16(1):72-76

本文对比了高岭石热分解及经碳热还原氮化作用制备赛隆过程中的相变情况，我们发现高岭石在这两种过程中发生的相变并不尽相同，加热高岭石最终形成莫来石和方石英过程中的相变，在其经碳热还原氮化作用制备赛隆的过程中是否出现，取决于温度、时间、Ｃ／Ｓｉ原子比、Ｎ２流量等实验条件，后者因受众多实验因素的影响，其相变过程远较前者复杂。因此，笔者认为这两种过程中相变是相同的观点有进一步探讨的必要。  相似文献