| Summary: | This thesis studies the links between plate tectonics and deep Earth processes during the breakup of northern Pangea from the Early Jurassic. To explore the major episodes of extensional and compressional tectonics during this break up, I establish a regional-scale plate tectonic model that links the kinematics of the Atlantic to the opening and closure of Western Tethys. My reconstructions include a revised history for the rifting of Greenland, Eurasia, Iberia and Africa away from North America and the early seafloor spreading that followed. I then combine this kinematic model for northern Pangea breakup with the history of rifting, spreading and subduction events in the western Tethys domain. Using recently published plate tectonic models for this region as a starting point, I critically assess conflicting end-member plate tectonic scenarios. I use mantle seismic tomography models to unravel the controversial subduction history of the Vardar Ocean and Alpine Tethys and to investigate the origin of an enigmatic high-velocity anomaly in the lower mantle beneath Africa. Geodynamic models with alternative plate kinematic histories and initial boundary conditions were built to link the revised history of subduction to a global models of mantle flow. To generate more robust plate reconstructions of the Mesozoic rifting between Greenland and North America, I developed models incorporating a quantitative description of continental deformation and margin restoration. To address major controversies about the duration of rifting, onset of seafloor spreading and the nature of the “transitional crust” in this area, I synthesised observations from seismic refraction experiments across Labrador Sea and Baffin Bay, carried out gravity inversion to map the crustal thickness within the conjugate rifted margins, and accounted for the addition of igneous material to the crust during and after rifting. Crust that underwent extension during rifting is restored to its pre-stretching location and the restored margins quantitatively ...
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