Controls on the emplacement of kimberlites and alkalic rock-carbonatite complexes in the Canadian shield and surrounding regions

The Canadian Shield and its extensions are traversed by an orthogonal syste m of northwest and northeast trending arch-style uplifts. These basement ar ches were formed by repeated vertical movements along pre-existing structur es during compressional and extensional tectonism connected with events in surrounding Proterozoic and Phanerozoic orogens and ocean basins. The arche s influenced patterns of sedimentation and tectonism in the intervening epi cratonic basins and marginal platforms throughout the Proterozoic and Phane rozoic. Movements on the arch structures also triggered minor magmatism and controlled the location and timing of alkalic rock-carbonatite, kimberlite , and related intrusions in the Canadian Shield, the Western Canada Sedimen tary Basin, and West Greenland. (C) 1999 Canadian Institute of Mining, Meta llurgy and Petroleum. Published by Elsevier Science Ltd. All rights reserve d.