METAMORPHIC TEXTURES IN ARCHEAN COPPER-ZINC MASSIVE SULFIDE DEPOSITS

A comparative study of sulfide textures has been carried out on samples from four Archean copper-zinc massive base metal sulfide deposits in Ontorio, Quebec and Northwest Territory Provinces, Canada. These deposits have undergone metamorphic recrystallization under a range of conditions, and results of this study indicate that certain sulfide textures may be used as qualitative indicators of metamorphic grade, whereas others cannot. The sulfide textures of most value in this regard are sulfide grain sizes, which increase with increasing metamorphic grade, and the presence or absence of sedimentary/diagenetic textures, which are destroyed at the lower amphibolite facies of metamorphism. Textures that appear to have little value as indicators of metamorphic grade are sulfide deformation textures, and triple junction point angles and their standard deviations. Refs.