Building mountain belts - the Appalachian model

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Each mountain belt on Earth is unique, but similar processes likely took place in the formation of all. One of those processes is the accretion of exotic fragments or terranes. My research program focuses on identifying such fragments in the northern part of the Appalachian mountain belt, interpreting from where on the Earth they were derived, and understanding how, when, and why they were attached to ancestral North America. My working model recognizes fragments in the northern Appalachian orogen and correlative belts in Europe derived from three separate microcontinents named Meguma, Avalonia, and Ganderia. We have made much progress toward understanding these fragments, but problems remain. This proposal focuses on two specific problem areas: (1) the part of Ganderia in central Cape Breton Island and (2) the part of Avalonia in northern mainland Nova Scotia. I will use field mapping as a basis to better define rock units, followed by mineral, textural, and chemical studies, dating, and isotopic analyses of carefully collected representative samples to decipher the ages and origins of the rocks in these areas.