The rising/settling of land due to its density.
 For a mountain to form, it must have an equal lower-crust as its upper-crust. Higher on top and higher on bottom.
For a mountain to form, it must have an equal lower-crust as its upper-crust. Higher on top and higher on bottom.

The rising/settling of land due to its density.
 For a mountain to form, it must have an equal lower-crust as its upper-crust. Higher on top and higher on bottom.
For a mountain to form, it must have an equal lower-crust as its upper-crust. Higher on top and higher on bottom.
