Mechanism for continental drift

The analysis of the gravitational spreading of floating ice shelves and continents has been extended to include the deformation of ocean basins. It is found that if a slight difference exists in the density of rock under two different oceans, and if this difference persists to depths of the order of 1000 km or more, stresses under the oceans may be great enough to cause one of these oceans to spread out and the other to contract. As a result of this process the center of any continent lying between the oceans will be shifted. The mechanism can be shown to be equivalent to a Vening Meinesz thermal convection cell.