West of the Mississippi River has many more mountains due to more recent orogenic processes. Blackhills, Rocky Mountains, Cascades, Sierras.... List goes on.
<span>The
process that takes place at convergent boundaries by which one tectonic
plate moves under another tectonic plate and sinks into the mantle as
the plates converge is called SUBDUCTION</span>
Explanation or are you askin to prove?
Answer is A 1100 ad thanks