Metamorphism at equal to, or higher than greenschist facies, will cause solid massive sulfides to deform in a ductile fashion and able to travel some distance into the country rock and along structures.
22.
Three major episodes of deformation and metamorphism were involved in the Aravalli Supergroup, including shearing, kink bands and crenulations etc . Metamorphic grades of the rocks generally range from greenschist facies to amphibolite facies.
23.
More common is the Hercynian metamorphism, which is associated with regional and periplutonic metamorphism caused by intrusions of granitic rock, diapthoresis and low grade metamorphism of volcanosedimentary formations of several tectonic units to the greenschist facies.
24.
The original sedimentary succession transformed into migmatites at its base, followed by gneisses, micaschists and finally sericite schists and chlorite schists at the top, the schists at the top only being metamorphosed under greenschist facies conditions.
25.
This elongate greenstone belt is characterized by Hausel as a synclinorium of metamorphosed volcanic, sedimentary and plutonic rocks that have been regionally metamorphosed to greenschist and amphibolite facies, and locally overprinted by a later retrogressive greenschist facies event.
