The central Taupo Volcanic Zone (TVZ) in New Zealand, the most productive of silicic volcanic centres, is flanked by younger andesitic stratovolcanoes to south. Small basaltic scoria cones occur along length TVZ, primitive which contain abundant xenocrysts, giving insight into mantle feeding TVZ. Here, we present major and minor element compositions olivine from eleven mafic eruptions spanning ...

H2O diffusion in a haploandesitic melt (a high-silica and Fe-free andesitic melt, NBO/T = 0.173) has been investigated at 1 GPa in a piston-cylinder apparatus. We adopted a double diffusion couple technique, in which one couple was composed of a nominally anhydrous glass with 0.01 wt.% H2O and a hydrous glass with 5.7 wt.% H2O, and the other contained the same nominally anhydrous glass and a hy...