巻号一覧
26 巻, 3 号
選択された号の論文の3件中1～3を表示しています
- |<
- <
- 1
- >
- >|
-
神津 俶祐, 八木 健三1941 年 26 巻 3 号 p. 101-121
発行日: 1941/09/01
公開日: 2008/03/18
ジャーナル フリーThe analysis of the garnet-hearing andesite from Amataki, Kagawa-ken, Japan, reveals some peculiarities in the chemical composition, relatively high in Al2O3, K2O and Na2O and relatively low in FeO, Fe2O3, MgO and CaO, compared with the average of 113 analyses of Japanese andesite (Tab. 3). It would be reasonable to ascribe these characteristics to the contamination of mica schist in the andesitic magma. The chemical analysis of the garnet gives the following result; SiO2=37.52, TiO2=0.48, Al2O3=21.03, Fe2O3=2.68, FeO=25.17, MgO-=4.66, CaO=6.06, MnO=1.89, H2O_=0.58, the total being 100.07% (Tab. 4). The chemical formula can be expressed by
(Fe'''8 Fe''166 Mg56 Ti3Ca51 Mn13)297 (Al192 Fe'''8)200 (Si296 Al3)299 O1200 in which Ti atom is considered to replace Mg instead of Si. From the above result, the mixing ratios of the end members are given as
Alm=58.14, Py=19.44, Sp=4.48, And=8.47, Gr=9.47 mol%. It is noteworthy that these ratios agree fairly well with those obtained by T. Takéuti by computation of Kôzu's formula, using the observed physical constants (Tab. 6). The chemical composition of our garnet resembles that of the garnet characteristic in the mica schists (Tab. 7). It is interesting to note that the most of the garnets found in the andesitic rocks also fall into this category (Tab. 8). From the above statements, it is concluded that the present garnet crystals were already formed in the mica schist and then they were taken into the andcsitic magma and have remained slightly dissolved in the cooling magma as xenocrystic minerals.抄録全体を表示PDF形式でダウンロード (1129K) -
特にトリディマイト化に關係ある礦化劑に就て犬塚 英夫1941 年 26 巻 3 号 p. 121-126
発行日: 1941/09/01
公開日: 2008/03/18
ジャーナル フリーPDF形式でダウンロード (754K) -
神津 俶祐, 加藤 磐雄1941 年 26 巻 3 号 p. 127-146
発行日: 1941/09/01
公開日: 2008/03/18
ジャーナル フリーOptical orientation, refractive index and extinction angle of the anorthite crystal newly ejected in 1940 from Miyake-volcano were measured in parallel with the anorthite from the same volcano erupted in 1874, and also with the crystals of Tarumae-volcano erupted in 1909, and with the same crystal occurring as phenocryst in basaltic andesite from Mitaki, near Sendai. The optical orientations were obtained. by using Leitz's universal stage (UT4), the results being given in Tabs. 9, 12 and 13; and the refractive indices were measured by a new model of Klein's total-reflectometer in which the millor is movable for the left or right side of the glass hemi-sphere. The results are given in Tabs. 15, 16 and 17. The extinction angles measured by a usual method in this case can be seen in Tabs. 19 and 20.抄録全体を表示PDF形式でダウンロード (1029K)
- |<
- <
- 1
- >
- >|