Terrane provenance and evolution in the northern appalachian orogen

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Remnants of ancient mountain belts form most of the Earth's continents, including Canada.  These remnants provide an opportunity to investigate mountain-building processes by exposing the internal architecture of the former mountains.  This proposal focuses on understanding the separate distinct components (or "terranes") that came together to form the part of the Appalachian mountain belt in southern New Brunswick and Nova Scotia between about 650 and 350 million years ago.  I want to figure out more exactly when the pieces came together, whether they came as numerous separate blocks or as a single composite block, and from where they came - possible source areas are any of the other continents, such as South America, Africa, and Scandinavia.  Although each mountain belt on the Earth is unique in the details of its development, certain elements are held in common, and knowledge and techniques gained in my work in eastern Canada may provide insight into the resolution of problems that geologists have in understanding other areas.  My work is based on detailed examination of the rocks in the field in order to understand the distribution of the many different kinds of rocks that occur in the mountain belt (a process known as geological mapping).  I collect representative samples and then in collaboration with colleagues who have the necessary equipment and expertise, I find out the ages of the rocks and determine their mineral and chemical compositions.  I use all of these different types of information to make interpretations about what was happening in the mountain belt at the various times when each kind of rock was forming.  Some features of the rocks, such as their isotopic compositions or magnetic and density characteristics, may help me to know what kinds of rocks underlie those that I see at the surface, information that will help me to interpret from where the various terranes were derived.  It is important to understand events and processes that happened even so long ago because they shaped the environment in which we now live, and provided the natural resources that enable us to not only survive but thrive.