Dorset coast Flashcards
what is durdle door
an arch
it is formed on a hard limestone headland
how was durdle door created
erosion by waves opened up a crack in the headland which became a cave and then developed into an arch
what is lulworth cove
a small bay
how was lulworth cove created
a gap was eroded in a band of limestone
behind the limestone is a band of clay which is softer so it was eroded and transported away
what is chesil beach
a tombolo which joins isle of portland to the mainland
what is behind chesil beach
a shallow lagoon called fleet lagoon
how was chesil beach formed
longshore drift
how are groynes protecting dorset coast
they trap material being transported by longshore drift which creates wider beaches so less erosion takes place
how are groynes also affecting dorset coast
by stopping material moving along the coast, they’ve starved areas further down the coast pf sediment making them narrower so more erosion takes place
what are sea walls and how are they protecting dorset coast
concrete walls placed alongg swanage beach and they reflect waves back out to sea preventing erosion
what can be bad about sea walls
they create a strong back wash which washes sediment into sea
what is beach replenishment and how is it protecting dorset coast
in 2005 sand and shingle dredged from the sea bed form a harbour was added to swanage beach making it wider which reduces erosion
what was bad about the beach replenishment
it cost £5 million
