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Divergent plate boundariescontinental rift systemsoceanic ridge system

Continental riftscontinental rift valleys

ssss1 Principal types of plate boundaries: (a) divergent; (b) convergent; (c), transform; thick lines represent plate boundaries and black arrows indicate relative motion between plates; (d) hybrid convergent‐transform boundary; red arrows show components of convergent and transform relative motion.

ssss1 Major features of continental rifts include rift valleys, thinned continental crust (blue) and lithosphere (brown) with volcanic‐magmatic activity from melts generated in rising asthenosphere (burnt orange).

Complete continental riftingsea floor spreading

ssss1 Model showing the growth of ocean basins by sea floor spreading from the ridge system following the complete rifting of continental lithosphere along a divergent plate boundary. Separated continental crust (light blue, topped with yellow sediments) and recently formed oceanic crust (dark blue striped pattern) are produced.