Fig. S1. Geological development and regional significance of an oceanic magmatic arc and its sedimentary cover: Permian Brook Street Terrane, South Island, New Zealand

Major element oxide crossplots of volcaniclastic sandstones from the Brook Street Terrane.(a) CaO v. SiO2 plot showing general inverse correlation; (b) MgO v. SiO2 showing a general inverse correlation; (c) Fe2O3 v. MgO showing a general positive correlation; (d) MnO v. MgO again showing a general positive correlation; (e) CaO v. MgO showing general positive correlation for Takitiumu Mountain and some Nelson area samples, but with some exceptions from the Nelson area; (f) K2O v. MgO showing a general inverse correlation.