Geology Reference
In-Depth Information
The reason continents rebound when the ice sheet retreats is related to the density of
the continental crust and the earth's mantle. (I explain density in Chapters 9 and 10).
The rock that the continents are made of is less dense than the mantle rock below it, so
the crust floats in the mantle like an ice cube floats in your water glass. If you add weight
to the ice cube (for example, you push it down with your finger), it sinks deeper into the
water. If you remove the weight, the ice cube bounces back up — or rebounds.
