Crustal thickness globe (updated)

**Update 11/2019**: Added a second version which has correct crustal thickness and no space for magnets. This model has 50x vertical exaggeration

This globe of the earth's topography opens to reveal the base of the crust (moho) which lies beneath it, an excellent aid for teaching and outreach in geology and geophysics. The relief at the surface and on the base of the crust are at the same scale (50x vertical exaggeration), and this is an excellent tactile way to explore the structures in the earth which lie beneath our feet

The earth's topography (i.e. where the surface of the earth is higher or lower) is controlled in large part by the thickness of the crust. Since the crust is lighter than the deeper mantle rocks, crust is buoyant and therefore "floats" at the earth's surface (if you want to know more about this - google "isostasy").

What this means is that most high places like mountains have roots! Much like an iceberg, the topography we see at the surface is small c