Anothite and Albite Glasses

Six shock experiments were performed with shock pressures of 16.9, 19.6, 24.0, 30.7, 34.5, and 40.8 GPa. Measured densities, p, are shown in Fig. 3.14a. X-ray diffraction data were measured with Mo-Ka radiation. Raman spectra in the range 115-1200 and 400-1400 cm-1 were measured for each sample [27,70]. 

The density variation in Fig. 3.14a is similar to that of SiC 2 glass. However, the maximum density increase (2.2%) at 24 GPa is smaller than that for SiC 2 glass (11% Okuno et al. [26]). At higher shock pressure, the density redecreases to almost the value of fused glass. 

The RDF curves calculated from observed X-ray intensity of all glasses are very similar. Therefore, structural variation of anorthite glass could not be detected by X-ray analysis. This may indicate that the density variation is due to very small structural variation of anothite glass produced by shock compression. This is consistent with small maximum densification (2.2 %). 

The corrected Raman spectra of glasses subject to shock are shown in Fig. 3.15a. The assignments of Raman bands were mentioned in the former section. With increasing shock pressure, the variation in relative intensity of the band near 580 cm-1 is significant. This variation is similar to that of density. 

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