To obtain the total erosive potential, the instantaneous distribution
of erosion is integrated over the tidal period. As demonstrated by
Fig. 3, this potential tends to be concentrated near the tidal extremes
(where the water level is for the most time). The erosion experienced
by each layer (dz) also depends on (the tangent of) its slope, with
more gently sloping elements tending to erode less than steeper elements
(Walkden and Hall, 2011).