苦土橄欖石 (Mg2SiO4) の状態方程式と地球中間層上部
1958 年 11 巻 2 号 p. 55-67
詳細
1958 年 11 巻 2 号 p. 55-67
An equation of state of forsterite based upon an ionic model has been deduced theoretically and the following results have been obtained.
1) Calculated variations of the density and incompressibility with pressure agree well with those obtained by K. E. Bullen for the B-layer. (Table 1) (Fig. 2)
2) The calculated activation energy value 3.29 e. v. is compatible with the experimental value by Hughes.
3) Variation of the activation energy with pressure is fairly less than expected. (Table 2) Using the data of distribution of electrical conductivity within the B-layer, the temperature gradient within it has been found to be about 1°/km. (Fig. 5)
4) A possibility of the polymorphic transition of forsterite from an olivine structure to a spinel structure is discussed. Comparing the lattice energies for both structures, it is shown that the transition is impossible. (Table 4)
