High-pressing preparation of rock glasses and their elastic properties

Melt glasses for seven types of rock ranging from acid to basic were prepared under 1.0 GPa on a multi-anvil pressure apparatus, YJ-3000 ton press. Densities and elastic properties of the melt glasses were compared with those described in previous studies. It was found that the glasses melted under 1.0 GPa were consistent in density with both naturally-occurring glassy rocks and artificially prepared glasses melted at ambient pressure. The densities of glasses are negatively correlated with the SiO2 contents and positively correlated with the (MgO FeO) contents. The compressive velocity (Vp) of glass tends to increase with decreasing SiO2 contents and increasing (MgO FeO) contents. The shear velocity (Vs) of glass tends to increase slightly with increasing SiO2 contents, which has little connection with the (MgO FeO) contents. It was calculated from densities and velocities that the elastic moduli of glasses are negatively correlated with the SiO2 contents and positively correlated with the (MgO FeO) contents.