Towards a new reconstruction of the Rodinia supercontinent using tectonic evidence from radiating dyke swarms linked to giant mantle plumes

The MacKenzie radiating mafic dyke swarm (1268+4 Ma) of Northern Canada has<br>been recognised as a product of a major tectono-thermal event in Earth history. The<br>radiating mafic dykes are interpreted by Fahrig (1987) as a failed arm of a triple<br>junction situated above a mantle plume. The MacKenzie mafic dykes extend for over<br>2000 km across the palaeo-continent of Laurentia with the focal point of the swarm<br>700 km north of Canada ( McKenzie and McKenzie, 1992 ).