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.******This work is important to geoscientists who work in areas from which components of the mountain belt may have been derived and/or to which former components may have been dispersed after the break-up of Pangaea. More broadly, the work is important to those who are trying to understand the fundamental processes of mountain building as exemplified in the northern Appalachian orogen. The relevance of my work is demonstrated by the extent of my collaborations with geoscientists from not only Canada but also the USA, UK, Spain, France, and Germany. My research involves students at both the undergraduate and graduate (MSc) levels and hence funding for students is the largest component of my budget. My students learn how to interpret rocks in the field, acquire and use analytical data, make public presentations, and write scientific papers. We anticipate that the new results, integrated with those from previous work and from other areas, will lead to a definitive and internally consistent model for northern Appalachian mountain building, with broad applicability to other mountain belts. Such understanding should lead to increased and more successful mineral exploration programs, especially if, as we anticipate, rock units related to those in mineral-rich areas in central Newfoundland and New Brunswick can be demonstrated to be present in Cape Breton Island. **