Foredune

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A foredune is a kind of dune ridge that runs parallel to the shore of an ocean, lake, bay, or estuary. Foredunes consist of sand deposited by wind on a vegetated part of the shore. Foredunes can be classified generally as incipient or established.[1]

Foredunes may begin as shadow dunes that form in the wind shadows of clumps of vegetation.[2] Several shadow dunes may eventually join to form an incipient foredune.[3] When an incipient foredune reaches a height of about 1.5 feet (0.5 m), it has a significant wind shadow of its own. Wind-blown sand will tend to fall on this incipient dune rather than traveling further inland. When a foredune becomes 3 to 5 feet (0.9 to 1.5 m) high, it may trap all of the wind-blown sand from the beach.[4]

In active dune systems, the foredunes appear closest to the sea or other body of water. However, some dune systems, such as those on eroding coasts, do not have foredunes. In those systems, other kinds of dunes may be closest to the water.[1]

References[edit source | edit]

  1. ^ a b Hesp, Patrick (2002). "Foredunes and blowouts: initiation, geomorphology and dynamics" (PDF). Geomorphology 48: 245–268. doi:10.1016/S0169-555X(02)00184-8. 
  2. ^ "Lake Michigan Coastal Dunes: Shadow Dunes". Calvin College. Retrieved December 10, 2012. 
  3. ^ "Lake Michigan Coastal Dunes: Foredunes". Calvin College. Retrieved December 10, 2012. 
  4. ^ "Lake Michigan Coastal Dunes: Active Foredunes". Calvin College. Retrieved December 10, 2012.