粘土科学
Online ISSN : 2186-3563
Print ISSN : 0470-6455
ISSN-L : 0470-6455
25 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
  • 西山 勉
    1985 年 25 巻 3 号 p. 101-106
    発行日: 1985/09/10
    公開日: 2011/09/20
    ジャーナル フリー
    Minerals comprising rocks are attacked by meteoric water and air and alter their structual and chemical properties. The minerals change to intermediate and/or new minerals in such weathering process. In this paper, relatively early products of the chemical weathering from mica minerals, chlorite and smectite are referred.
    The vermiculite weathered from biotite in schalstein at Ofuku, Yamaguchi Pref. has cube-like materials in about 50Å size at the edge of the crack on surface and in an exforiated interlayer space. Chlorite-vermiculite interstratified minerals weathered from chlorite in schalstein and sedimentary rocks from Tobigamori, Iwate Pref. are estimated comprising about 50% of a vermiculite-like layer by X-ray diffraction analysis. The degree of swelling of their interlayers after various K+-treatments distinctively change among samples and with particle sizes of the samples. The interstratified chlorite-vermiculite alters to kaolinite with the relationship of syntaxy.
  • 吉村 尚久
    1985 年 25 巻 3 号 p. 107-112
    発行日: 1985/09/10
    公開日: 2011/09/20
    ジャーナル フリー
    Illite/smectite mixed-layer minerals occur widely in diagenetic process of argillalaceous and acid pyroclastic sediments. The relative proportion of constituent layers and ordering in the mixed-layer structure are regarded as reflecting formation temperature (Fig. 1). Chemical changes from random to regular interstratification are remarkable in tetrahedral Al and octahedral Al/(Al+Mg+Fe) ratio (Fig. 2).
    Chlorite/saponite mixed-layer minerals are found in MgFe bearing sediments such as basic-intermediate pyroclastics. The proportion of chlorite layers in the interstratification is discontinuous and is concentrated on ranges of less than 10, 50, 75 and morethan 90%. Randomly interlayering of chlorite/saponite occurs as replacement products of volcanic glass. An increase in chlorite layers with increasing burial depth is observed in the Miocene pyroclastic rocks of Yamagata-Yoshino (Fig. 3). Whereas corrensite type minerals occurring as cementing materials of andesitic sandstone are found over the thick strata regardless of burial depth. Chemical changes of chlorite/saponite mixed-layer with increasing burial depth are characterized by an increase of tetrahedral Al and octahedral Fe (Fig. 4).
  • 白水 晴雄
    1985 年 25 巻 3 号 p. 113-118
    発行日: 1985/09/10
    公開日: 2011/09/20
    ジャーナル フリー
    Formation of clay minerals by hydrothermal action and their mineralogical properties have been reviewed with some discussions on the relations of hydrothermal alteration to weathering and diagenes, on the chemical compositions of dioctahedral 2:1 clay minerals and chlorite minerals, and on the polytypes of some sericite minerals. There are wide variations in the parent materials, the water resources, the alteration conditions and processes of the hydrothermal alterations, and almost all kinds of clay minerals with moderate crystallinity are found in the alteration envelopes in Japan. Hydrotherrnal dioctahedral Inica minerals known as sericite are characterized by their mineralogical properties intermediate between muscovite and illite. It is noticed that the typical fine-grained clay minerals in the dioctahedral 2:1 type and chlorite minerals (sericite, illite, glauconite, niontmorillonite, leptochlorite, sudoite, and donbassite) show nonintegral hut approximately fixed populations of interlayer cations.
  • 歌田 実
    1985 年 25 巻 3 号 p. 119-125
    発行日: 1985/09/10
    公開日: 2011/09/20
    ジャーナル フリー
    Authigenic minerals, including clay minerals, have been formed at subsurface of the earth under very wide conditions. Practically the “zone” which is defined by assemblage of them is convenient for recognizing a restricted physicochemical condition. The comhnation, sequence, morphology, relation to stratigraphy and geologic structure of these zones indicate more details of varying conditions. The author cites an instance of various kinds of zoning which are constituted by the zones of zeolite-lay-ilica minerals, correlating to different alteration facies.
  • 鎌田 裕
    1985 年 25 巻 3 号 p. 126-133
    発行日: 1985/09/10
    公開日: 2011/09/20
    ジャーナル フリー
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