Explanation: The displacement of the mantle by the continental or the ocean crust depends on a condition known as <span>isostasy which describes the gravitational equilibrium between both the mantle and the crust of the Earth. If </span><span>isostasy is not preserved, this would mean that the equilibrium between the crust and the mantle is not maintained and that the crust would displace a volume of mantle. The amount of mantle to be displaced usually depends on the density of the crust.
