Petrography of rocks from the Western Chain of the Snares Islands (Note)

Abstract The Western Chain of the Snares Islands consists mainly of jointed muscovite granite, which locally is strongly crushed. Previously described fragments of schist from Rua islet are possibly remnants of roof pendants; they are further discussed. The schist includes varieties with biotite and muscovite and with biotite alone, and these rocks appear to be similar to schists of the Tin Range, Stewart Island. A secondary (hydrothermal) origin for much of the abundant muscovite of the Western Chain granite is suggested.