south of Palm Beach, Florida. Swamps, marshes, a coastal wetlands produce peats and other organic
matter. Too light to remain in place under continued wave action, they are ultimately washed offshore
unless stabilized.
Littoral materials are transported along the shore as shown. Figure 3. As waves approach the
shore, they move to progressive shallower water where they bend or refract until finally breaking at an
angle to the beach. The broken wave creates considerable turbulence, lifting bottom materials into
suspension and carrying them up the beach face in the general direction of wave approach. A short
distance up the beach, the motion reverses direction back down the beach slope. In this case, the
downrush does not follow the path of the advancing wave but instead, moves down the slope in response
to gravity. The next wave again carries the material upslope, repeating the process, so that each
advancing wave and the resulting downrush move material along the beach in the downdrift direction.
As long as waves approach from the same direction, the alongshore transport direction remains the same.
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