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Katherine D. Photograph |
WELLFLEET BEACH , WELLFLEET - 41.91N,
70.02W
This is a dune at Marconi beach in
Wellfleet, Cape Cod. This feature contains beach grass, sand
and small trees. Three
things are required for a dune to form: a
large amount of sand, high wind speed that can move the
sand, and a place for the sand to be deposited. Ripples on
the dunes form when sand begins to pile up. Wind continues
to move sand up to the top of the pile. The collapsing sand
only stops when it reaches the perfect steepness to keep
the dune from slipping, or collapsing. Every dune is
different, but most dune's angle of repose is between 30 and
34 degrees.
With
its roots reaching deep into the freshwater below the dunes
and its horizontal runners spreading out under the sand
around it, the beachg rass stablizes the dunes. The
dunes shelter people and buildings from wind, and protect
the coast from incoming waves
- Katherine D.
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