Abstract
In order to elucidate many geophysical problems induced from the global techtonics, dynamics of the mass transfer has attracted an interest. In association with the seismic researchs, material transformations, such as transition, decomposition, recrystallization, melting, etc. have been also greatly intrested under the conditions of heating, compression and stress field. Pressure-induced amorphizations of many minerals such as quartz, cristobalite, tridymite, anorthite, serpentine, fayalite and several other hydrates have been reported. These amorphizations and shear-instability will play a role to conduct the transformational ductile flow in the subduction zone, which would be the origin of the deep earthquake. Several different types of the pressure-induced amorphization were proved by the X-ray diffraction studies under high pressure and heating condition using multianvil high-pressure appararus and diamond anvil pressure cell. If the amorphization is the quenchable case, the pressure-quenched amorphous substance was examined by electron microscope, Raman spectrosope, EXAFS together with X-ray diffraction study.
