Textural relations of porphyroblasts in the Salm phyllites from Vielsalm and Salm-Chateau, Ardennes, Belgium

Abstract

The effects of two deformation phases can be seen in the rocks of Vielsalm and Salm-Chateau; the first deformation produced the principal schistosity and the second a crenulation cleavage. The main metamorphism and the, formation of chloritoid, kaolinite and possible garnet porphyroblasts are later than the development of the first schistosity but earlier than the crenulation. It is very probable that the schistosity in both these places represents the same period of deformation. This deformation may be Hercynian, but it cannot be definitely ascertained. If this were true, the metamorphism would be post-tectonic with respect to the principal Hercynian deformation.