Deposition Flashcards
How is a spit formed
Longshore drift transports sand and moves past the bend and deposits it in the sea
Winds and waves will curve the spit
Sheltered area behind the spit is protected from waves the sheltered area will become mud flat or slag marsh
How is a bar formed
When a spit joins two headlands together
Bar cuts off the bay between the headlands from the sea
So a lagoon can form behind the bar
How is a sand dune formed
When sand is deposited by longshore drift and is moved up the beach by the wind
Obstacles cause wind speed to decrease so sand is deposited
Sand is colonised by plants and grasses so vegetation stabilises the sand
Forms small dunes called embryo dunes
The oldest dunes migrate inland