• The Journal of the Petrological Society of Korea
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• v.6 no.1
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• pp.52-64
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• 1997

Pelitic rocks of southwestern Nova Scotia have been affected by widespread contact metamorphism due to the intrusion of the Shellburne Pluton, with aureole up to 15 km wide. Well-preserved pseudomorphic textures indicate that common staurolite and andalusite metacrysts formed at the expense only of plagioclase, muscovite and biotite. Excess components (K, Na and Ca) from such replacement reactions imply extensive metasomatism throughout the contact aureole. Modal analysis of a typical andalusite-bearing rock indicates a one-to-one volume ratio of product to reactant. However the products of the replacement reactions contain approximately three times more aluminum than the reactants, indicating that the regional metasomatism also involved aluminum.