On the interpretation of retrograde reaction textures in granulite facies rocks

Abstract

Retrograde reaction textures, such as partial pseudomorphs, coronae and symplectic coronae are a relatively common feature of granulite facies rocks and represent evidence of change of mineral modes or assemblages. Thus, such reaction textures represent one of the more potentially useful indicators of retrograde P-T evolutions. However, the interpretation of such textures requires the simultaneous consideration of the formation of the texture itself in terms of the spatial relationships in a rock, and of the changes in P-T conditions that drove the development of the reaction texture. Calculated phase diagrams provide a robust framework in which to consider reaction textures, especially via ..