Additional features of the shocked samples observed via TEM. (a) HRTEM image of olivine shocked at 18 GPa. The upper part of the olivine exhibits a crystal structure similar to that of olivine shocked at 14 GPa, whereas the lower part resembles the characteristics of olivine shocked at 11.7 GPa (Kudoh & Takeda 1986). The dashed boxes indicate the locations for FFT analysis in the upper and lower parts. The dashed box on the upper right marks the area corresponding to image (b). (b) HRTEM image of olivine, showing numerous well-defined olivine fragments distributed within a matrix of olivine with less distinct lattice structures. The FFT pattern reveals polycrystalline rings, indicating structural disorder. (c) BF TEM image of olivine shocked at 18 GPa, where residual SiO₂ from the synthesis is visible. The dashed box marks the location of image (d). (d) FFT patterns of olivine and SiO₂. The white dashed lines serve as symmetry guides for the olivine crystal structure, whereas the yellow dashed lines highlight the amorphous ring of SiO₂.