Seismic waves travel at different speeds according to type. what is the speed of seismic waves from fastest to slowest?

The three different types of seismic waves are primary waves, secondary waves, and surface waves. Primary waves are the fastest type of seismic wave. They form rocks by changing their volume, which can be done by compressing and expanding rapidly. Secondary waves are slower than primary waves. They deform rocks by changing their shape. Surface waves are the slowest of the trio and pass around the border of the Earth rather than going through it.

heat from the core of the earth causes convection currents to occur in the mantle. these currents slowly move the crust around.