カンラン石,斜方輝石,ザクロ石を含む超塩基性岩の温度圧力推定への最小2乗法の応用
1984 年 79 巻 11 号 p. 443-454
詳細
1984 年 79 巻 11 号 p. 443-454
The mathematical background has been established to evaluate the equilibrium pressure and temperature of ultramafic xenolith by the application of least squares technique to the equilibrium among olivine, orthopyroxene and garnet. Estimated pressures in the approximated system SiO2-Al2O3-FeO-MgO-CaO are slightly greater than those in the additional correction of Mn-Ni-Cr-Ti for the granular type of lherzolites and are shifted to lower pressure sides for the sheared lherzolites. The inflection in the paleogeotherm beneath northern Lesotho is observed at the depths 150 km.
