<P> The lowest velocities are near the base of the glacier and along valley sides where friction acts against flow , causing the most deformation . Velocity increases inward toward the center line and upward , as the amount of deformation decreases . The highest flow velocities are found at the surface , representing the sum of the velocities of all the layers below . </P>
<P> The lowest velocities are near the base of the glacier and along valley sides where friction acts against flow , causing the most deformation . Velocity increases inward toward the center line and upward , as the amount of deformation decreases . The highest flow velocities are found at the surface , representing the sum of the velocities of all the layers below . </P>
in a cross-section of a glacier the greatest flow velocities ( speeds ) occur
in a cross-section of a glacier the greatest flow velocities ( speeds ) occur
at the surface
at the surface