Ostwald ripening indicated by mineral and melt inclusions in anorthite megacryst from Ogi peninsula, Sado Island

Abstract

We examined mineral and melt inclusions in anorthite megacrysts from Ogi Peninsula, Niigata, Japan. The dominant mineral inclusions are Fe-Cu-Ni-sulfides that occur with mafic melt inclusions. In addition, volatile components such as S and Cl were detected in the melt inclusions. These results suggest that the present anorthites have grown in volatile-rich condition owing to the mixing of crustal components into basaltic magma chamber.