Steep crystalline-basement faults, commonly indicated by potential-field anomalies, played a crucial role in evolution of continental cratonic platforms. In the Phanerozoic Western Canada Sedimentary Province, history of crustal block movements and warps is reconstructed from the distribution of depocenters, lithofacies and structures in structural-formational etages in sedimentary cover. Each etage is a rock succession formed during a particular tectonic stage; regional tectonic restructuring closes each stage, and the next stage represents a new tectonic regime. Practical tectonic analysis, based on observation of rocks and geophysical data, is a reliable guide for deciphering a region's geologic history and for resource exploration."