transportation and deposition Flashcards
what is transportation?
the movement of eroded material.
what is longshore drift?
the zigzag movement of sediment along the coast line from swash and backwash.
what is the direction of longshore drift determined by?
prevailing wind.
what is deposition?
when material being transported by the sea is due to a loss in energy.
why does deposition occur?
•deposition occurs when the sea transporting sediment loses energy and slows down.
•its linked with constructive waves, when the swash is greater than the backwash.
when is deposition most likely to occur?
•when waves enter an area of shallow water.
•waves enter a sheltered bay, creating beaches.
•when the wind speed is low.
•when a river flows into the sea reducing wave energy.
•there is a good supply of sediment nearby.
how does longshore drift occur?
•when waves approach the beach at an angle due to the direction of the prevailing wind which is called swash, it often transports sediment with it.
•the wave and the sediment it carries returns straight back down the beach because of gravity, this is called backwash.
•this continues overtime and the waves transport seditment along the coast in a zigzag motion.
