粘土科学
Online ISSN : 2186-3563
Print ISSN : 0470-6455
ISSN-L : 0470-6455
20 巻, 3 号
選択された号の論文の5件中1~5を表示しています
  • 武司 秀夫, 宇野 泰章
    1980 年 20 巻 3 号 p. 67-78
    発行日: 1980/09/25
    公開日: 2011/09/20
    ジャーナル フリー
    Previous works on bentonite deposits in United States, and bentonite and acid clay deposits in Japan are reviewed briefly.
    The outlines of genesis of bentonite deposits are discussed: bentonite deposits formed by alteration of volcanic ash or tuff in situ are most widely distributed abroad and in Japan also. Hydrothermal alteration (including deuteric alteration) of igneous rock and material is next an important mode of origin.
    Bentonite and acid clay deposits of economic importance in Japan are discribed on the location, parent rock, main exchange cations, form of deposit, geologic age of formation, etc. Some deposits abroad are also described on main exchange cations and form. of deposit.
    Montmorillonite (the main constituent mineral of bentonite) is discussed first on terminology: the term smectite can be used as a group name for all clay minerals with an expanding lattice except vermiculite, and montmorillonite is a specific mineral name of the smectite group.
    Dioctahedral smectite is the main constituent clay mineral in bentonites except quite a few number of bentonite deposits composed of trioctahedral montmorillonite. In Japan no deposits composed of trioctahedral smectite, are found.
    Variations in composition in montmorillonite-beidellite series of smectite are nearly between end member of montmorillonite and boundary of montmorillonite and beidellite
    Methods for caluculating structure formulae for the dioctahedral smectite are proposed:
    1) fixed anionic charges 22 in form of O10 (OH, F)
    2) fixed anionic charges, including charges of exchange cations (0.33)
    3) fixed cationic number (6.00)
    Populations of tetrahedral and octahedral sheets of Cheto and Wyoming montmorillonites are compared among calculations made with the second method by Grim and Kulbicki, with the third method by Grim and Giiven, the first method by Takeshi and Uno.
    Cheto montmorillonite has the composition near end member of montmorillonite, though W yoming montmorillonite has the composition near the boundary of montmorillonite and beidellite. Tsukinuno and Odo montmorillonites have compositions near Wyoming, and N akajo montmorillonite has the composition near end member of montmorillonite, nearly the same as that of Cheto.
    Weathering of dioctahedral smectite is discussed:(Mg, Ca) montmorillonite like Nakajo, having the composition near end member of montmorillonite, is easily altered to halloysite in the wet climate and mild temperature in the following order:(Mg, Ca) montmorillonite →(H, Mg, Ca) montmorillonite →(H, Mg, Ca) abnormal montmorillonite → mixed-layer of montmorillonite and halloysite. Odo montmorillonite is not easily transformed like Nakajo one, because its composition of montmorillonite layer is near the boundary of montmorillonite and beidellite, although its main exchange cations are Mg and Ca, which are largely replaced by hydrogen at the surface of the deposit.
    Finally differential thermal analysis and the phase transformation of montmorillonitebeidellite series are discussed briefly.
  • 野田 修司
    1980 年 20 巻 3 号 p. 78-82
    発行日: 1980/09/25
    公開日: 2011/09/20
    ジャーナル フリー
    A new simple method for determining the cation exchange capacity of natural zeolites is presented. The natural zeolites used in this study were from Shimane Prefecture, Japan.
    The most suitable measuring conditions of this method were obtained for the natural clinoptilolite, the natural mordenite, Na+ exchanged clinoptilolite and mordenite, and Mg2+ exchanged mordenite. As the result, the natural clinoptilolite was saturated with NH+4 ions for about a month at room temperature by treating with 100 ml of 1 N AcONH4solution, but for only one day at 80°C. And the all NFI+4 ions adsorbed in the natural clinoptilolite were extracted for about one hour by treating with 100 ml of 10% KCl solution.
    The CEC value of the natural clinoptilolite obtained by the Schollenberger's method was smaller than that obtained by the method presented in this report. Then the exchange rate of each cation with NH+4 for the natural clinoptilolite was investigated, and it was found that exchangeable Ca2+ and Mg2+ (especially Mg2+) ions contained in the natural clinoptilolite were exchanged with NH+4 ions very slowly at room temperature.
  • 分析電顕による検討
    田崎 和江
    1980 年 20 巻 3 号 p. 83-90
    発行日: 1980/09/25
    公開日: 2011/09/20
    ジャーナル フリー
    By using a transmission electron microscope (TEM) equipped with an energy dispersive electron-microprobe analyzer, genetical relationships between micro-morphology and chemical composition of kaolin minerals were investigated.
    The TEM observation revealed that the kaolinite specimens, which show a 7Å basal reflection in X-ray diffraction diagram, are commonly mixtures of particles with various morphology such as film, hexagonal plate and long tube (Table 1). The chemical compositions of these kinds of particles are different from one another as shown in Fig. 1 and 2. Triangular plot of SiO2, Al2O3 and ΣFeO of the Kibushi clay (No.7 in Fig.2) shows limited chemistry of each morphology with slight overlap that SiO2 content of the film of indefinite primitive form is less than that of hexagonal plate, whereas, ΣFeO is lower in the latter. However, the chemistry of the Austria kaolin (No.5 in Fig.2) shows the reverse trend in SiO2 content. This reverse trend might suggest the difference in the source material.
  • 立山 博, 金原 啓司, 陣内 和彦, 木村 邦夫
    1980 年 20 巻 3 号 p. 91-96
    発行日: 1980/09/25
    公開日: 2011/09/20
    ジャーナル フリー
    An interstratified mineral of muscovite and vermiculite was found as an alteration mineral of muscovite in the crystalline shist at Mikamo-cho, Miyoshi-gun, Tokushima Prefecture. The grain size of this mineral was fairly large for taking the single crystal photograph by X-ray. The crystal structure of this mineral was estimated by X-ray powder diffraction and X-ray single crystal methods. The stacking sequence of this sample seems to be just the same with that of 2 M polytype of muscovite. The lattice constants and optical properties are as follows:
    a=5.228 (7), b=9.041 (8), c=25.01 (2)Å, β=94.88 (8)°,
    and
    a∧Y=3-5°, b=z, c∧X=0-4°, 2V=-31°.
    These optical properties are close to those of 2 M muscovite.
  • 青峰 重範
    1980 年 20 巻 3 号 p. 97-98
    発行日: 1980/09/25
    公開日: 2011/09/20
    ジャーナル フリー
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