الفهرس 
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Abstract
• Beaches are in a delicate balance between sand supply and natmaI forces of
erosion. Beaches can be divided into eroding, stable, or accreting depending on the
rate of supply and loss of littoral sediments. Beach erosion is for the most part
episodic, with major retreats in the shoreline occurring during usually intense storms
(Komar, 1983). The shore is considered stable when the longshore rates of supply and
loss are equal. Beach erosion induced from sea level rise, land subsidence, storm
waves, reduction of sediment supply to the littoral zone, removal of loose material
from the beach by wind action, longshore sediment transport, sorting of beach
sediments and mans interventions (dams, protection works, removal of material from
the beach). The principal source of sand transport to beaches include: rivers, sea-
clift7dune erosion, and material. of biologic origin, such as shells, coral fragments, and
skeletons of small marine organisms.
Waves are responsible for driving the nearshore currents system which, in turn, is
responsible for the important process of longshore sediment transport. When waves
approach the coast at an angle, they cause sand to be transported along the shore i.e.
longshore sediment transport (CERe, 1984). ThisIongshore current, under certain
conditions, may turn and flow seaward in which is known as a rip current Qnman and
Brush, 1973). Longshore transport results from the stirring up of sediment by the
breaking wave and the movement of this sediment by the wave energy in an
alongshore direction. At the breaker line, as the waves break, great disturbance takes
place due to dissipation of the wave energy. Longshore transport is divided into two
general classes: transport parallel to the shore Qongshore transport) and longshore
perpendicular to the shore (cross-shore transport). The material that is transported is
called littoral drift (CERe, 1984).
The Rosetta promontory is one of the most important areas for trade, agriculture and
fishing activities in the northwestern coast of the Nile Delta, The Rosetta cityused to
have a great importance since the latest Pbaraonic periods.