Clay Science
Online ISSN : 2186-3555
Print ISSN : 0009-8574
ISSN-L : 0009-8574
Volume 4, Issue 3
Displaying 1-5 of 5 articles from this issue
  • SHIGENORI AOMINE, ATSUHIKO INOUE, CHITOSHI MIZOTA
    1972 Volume 4 Issue 3 Pages 95-103
    Published: 1972
    Released on J-STAGE: September 20, 2011
    JOURNAL FREE ACCESS
    Volcanic ash soils were collected from 8 sites which distributed from around 35°30' to 41° of the south latitude in the Central Valley of Chile, and their clay minerals were studied mainly by x-ray, differential thermal and electron microscopical methods. The soils examined could be classified into three large groups according to the major clay minerals; allophanic, metahalloysitic, and allophane-metahalloysitic soils.
    The allophanic soils correspond to “trumao” soils derived from young volcanic ashes, and the metahalloysitic soils to “rojo arcilloso” soils derived from old volcanic ash materials. The allophane-metahalloysitic soils are morphologically “trumao” soils, but their parent materials would be mixtures of both young and old ashes.
    Besides the major clay minerals, the allophanic soils contain imogolite, kaolinite, chlorite, gibbsite, irregularly interstratified chloritevermiculite and occasionally smectite, vermiculite and illite. In contrast to those soils, the minor clay minerals of the metahalloysitic soils are halloysite, chlorite and irregularly interstratified minerals of halloysitemetahalloysite and vermiculite-chlorite. They sometimes contain illite, vermiculite, smectite, gibbsite and irregularly interstratified smectitevermiculite. The clay mineral assemblage of allophane-metahalloysitic soils is similar to the metahalloysitic soils excepting abundant allophane.
    Imogolite in the soils was identified by its characteristic x-ray diffractions, endothermic reaction, and fibre-like shape, but its particles are rather short in length. Imogolite seems to occur very widely in the “trumao” soils derived from young volcanic ashes in Chile.
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  • Y. TOKASHIKI, K. WADA
    1972 Volume 4 Issue 3 Pages 105-114
    Published: 1972
    Released on J-STAGE: September 20, 2011
    JOURNAL FREE ACCESS
    Si, Al and Fe extracted from volcanic ash soil clays by the treatments with Na2S2O4-NaHCO3-Nacitrate, 2% Na2CO3 and 0.5N NaOH were determined. A procedure was developed for the simultaneous determination of Al and Fe by ferron after the removal of citrate from these extracts by wet oxidation using H2SO4 and H2O2. The percentage recovery of Si added to the respective extracts of volcanic ash soil clays was in the range 99±2, while that of Al 97±3. In the proposed procedure, the recovery of Al added to each sample solution was tested and used for correction.
    The weight loss of the clay by each dissolution treatment and the sum of the amounts of then extracted SiO2, Al2O3 and Fe2O3 were compared. These values were evaluated from the point of view of semiquantitative mineralogical analysis of volcanic ash soil clays.
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  • SUSUMU SHIMODA
    1972 Volume 4 Issue 3 Pages 115-125
    Published: 1972
    Released on J-STAGE: September 20, 2011
    JOURNAL FREE ACCESS
    An interstratified mineral of mica and montmorillonite was found in some drill cores at the Niida mineralized district near the Shakanai mine. The interstratification is produced by a two component stacking of about 60 9 mica-like layers and about 40 9 montmorillonite-like layers. The DTA curve shows double endothermic peaks for the dehydroxylation of the silicate layer. The infra-red data give 1 M illite and montmorillonite bands and band shifts, when heated to 500° and 550°C. Chemical composition: SiO2 47.13%; TiO2 0.33%; Al203 31.76%; Fe2O3 0.87%; MgO 0.35%; MnO trace; CaO 0.94%; K2O 2.85%; Na2O 0.04 9; H2O+8.66 9; H20-6.97%; total 99.90%.
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  • K. WADA, T. HENMI
    1972 Volume 4 Issue 3 Pages 127-136
    Published: 1972
    Released on J-STAGE: September 20, 2011
    JOURNAL FREE ACCESS
    The micropore status of air-dry and preheated imogolites has been examined by measuring retention of (CH3) 4NCl, (C2H5) 4NCl, (C4H9) 4NCl, (CH3) 2 (C6H5)(C6H5CH2) NCl and water. Interactions between the salt and imogolite were followed by observing the moist or dry appearance of the clay-salt mixture when the salt is deliquescent and by observing the changes of the x-ray pattern of imogolite. The adsorption of water vapor at various relative humidities was determined by gravimetry.
    No stoichiometrical relationship was found between the maximum amounts of different salts retained by imogolite. The volume ratios of the salt and water at their retention maxima to the solid phase of imogolite were calculated from the retention data. They were found in ranges 1.3 to 1.6 and 0.5 to 1.1 for the air-dry and preheated imogolites, respectively. The difference between them gave a measure of the void ratio of the inter-structure-unit pores. The collapse of these pores by heating and its inhibition by the salt uptake were indicated by x-ray analysis. The volume ratios obtained with the preheated imogolite increased with the increasing size of the cation up to (C4H9) 4N+, but the largest cation (CH3) 2 (C6H5)(C6H5CH2) N+ gave the lowest value. On this basis, the presence of the intra-structure-unit pores of about 10Å in diameter was inferred.
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  • HARUO SHIROZU, SHOJI HIGASHI
    1972 Volume 4 Issue 3 Pages 137-142
    Published: 1972
    Released on J-STAGE: September 20, 2011
    JOURNAL FREE ACCESS
    X-ray diffraction data for the sericite minerals from the Kuroko deposits are outlined along with a method for presentation of the variation in the diffraction patterns.
    The samples are obtained from the alteration zones of the typical Kuroko deposits of the Shakanai, Hanaoka (Matsumine), Kosaka, and Furutobe mines of Akita Prefecture. Diffraction analysis for the oriented aggregates has revealed that they are sericite and interstratified sericitemontmorillonite with various amounts of expandable layers. For the minerals which are interstratified with from zero to small amounts of expandable layers, the peak widths of the 10-11Å and 5Å reflections were chosen to examine the extent of the interlayering and plotted in a diagram. The result indicates a close relationship of the extents of interlayering to their modes of occurrence. Polytypes identified in the samples are 2M1, 1M, and 1Md, the last of which is found only in the interstratified minerals.
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