Figure 1
From: Estimating the viscosity of volcanic melts from the vibrational properties of their parental glasses
Spectroscopic parameters as a function of SiO2 content (mol%) of glass. Brillouin (a) and Raman (b) data of samples (Table 2) from this study (empty circles) and the literature (solid symbols) as a function the SiO2 (mol%) content of the glasses. The ratio of the bulk (K) and shear (G) elastic moduli is calculated (Eq. 3) from the Brillouin velocities (Table 2), whereas the boson peak position \({\omega }_{BP}\) is retrieved by fitting the low-frequency Raman spectra of the glasses using a log–normal function (see “Materials, literature data and methods” for details). Red lines in (a) and (b) are linear fits of the data with Eqs. (4, 5), respectively. Literature data in (a) are: (squares) Whittington et al.35, (hexagon) Richet and Polian40, (diamonds) Hushur et al.41, (filled triangle) Zanatta et al.39, (unfilled triangle) Novikov et al.36. Literature datum in (b) is from Zanatta et al.39.
