Relationship between paleomagnetism and tectonics during signature events in the assembly and dispersal of supercontinents

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The assembly, breakup and dispersal of supercontinents over the past billion years (Rodinia, Gondwana and, most recently, Pangea) is a fundamental plate tectonic process on Earth. The succession of global paleogeographies seen in the supercontinent cycle provides an important context for understanding past paleoclimatic extremes and the diversification of life. Much of the history of supercontinent assembly and dispersal is recorded as rifting, subduction and mountain building along plate boundaries, often in independent crustal blocks called terranes. Paleomagnetism is a key quantitative geophysical tool for defining the past motions of continents and terranes and the structural evolution of mountain belts. Paleomagnetism, in conjunction with geochronology, is ideally suited to deduce the orientation and timing relationships between terranes and adjacent continents, to resolve paleogeography, structural rotations and the timing of deformation. My proposed paleomagnetic and tectonic research program investigates key questions in the interaction of the paleocontinent Laurentia (North America + Greenland and Northern Ireland, Scotland) with Avalonia and other terranes from the Late Precambrian (ca. 630 million years ago) through the mid Paleozoic assembly of Pangea. Fieldwork is anticipated to take place on a project-by-project basis in Atlantic Canada, Yukon and Morocco. Paleomagnetic laboratory work is to be done by arrangement with the premier facility at the University of Windsor. Associated geochronology and other supporting research will be done as an integral part of student theses and via collaborations. This research is based solidly on my existing research strengths, and represents many undergraduate, graduate student and other HQP opportunities. The overall goal of my proposed program is to solve the key questions concerning the tectonic relations between Laurentia, Avalonia, elements of West Gondwana and other terranes which lie at the core of the as-yet poorly understood global paleogeography of the Late Precambrian breakup of Rodinia through the Paleozoic assembly of Pangea.