Modified C-O-H solubility model of Dixon et al. (1995) (after Wetzel et al. 2015). The solid lines are isobars (crustal depths) and dashed lines are isopleths indicating the fraction of H2O in the vapor phase (XH2O). H2O data are from Hauri et al. (2015). Orange circles are A17 melt inclusions; other symbols are bead data (see Fig. 1). The pressure contours are not for a fixed activity of C, but Wetzel et al. (2015) found that this model and the experimental solubility curve for graphite saturation (Fig. 2) yielded identical C (ppm) vs. pressure curves.