Laboratory-based electrical conductivity model of a subduction zone. (A) Considered mineralogy and thermal profile, after Schmidt and Poli (1998) and Grove et al. (2012). (B) Corresponding electrical response based on laboratory studies (see text for details). The green area underlines that the distinction between hydrous minerals and partially molten rocks is not possible based on electrical conductivity only, because these phases have similar electrical conductivity values at conditions relevant to subduction.