High-magnesian andesite from Mount Shasta: A product of magma mixing and contamination, not a primitive melt: COMMENT AND REPLY: COMMENT

Abstract

[Streck et al. (2007)][1] state that primitive andesite lavas (Mg# > 0.6; 53–63 wt% SiO2) from Mt. Shasta are not primary melts, but instead are mixtures of evolved, high-Sr/Y, low-Mg# dacite with primary, low-Sr/Y, high-Mg# basalt. They propose that this mixing forms primitive andesites worldwide