A. The lithospheric breakup-collision coupling system, in which collisional thickening of the continental crust is coupled with lithospheric breakup due to asthenospheric upwelling for active rifting. B. The seafloor spreading-lithospheric subduction coupling system, in which the oceanic slab is subducted to depths of >80-100 km for the gravitational pull, providing far-field stresses for passive rifting.