explain how spits form.
constructive waves approach at an angle to the beach. the strong swash pushes the sediment up the beach however the weak backwash pulls it back at a right angle to the coast. the longshore drift current transports the sediment. the sediment builds up at the end of the beach
explain how stack like old harry form.
old harry is a sea stack found in dorset. the head which is made of chalk juts out into the sea. at high tide the destructive wave erodes the headland through hydraulic actionand corrosion. lines of weakness in the headland are enlarged by erosions forming a cave. if there are caves on both sides of the headland and they erode through it, it forms an arch. over time the arch becomes too heavy and collapses leaving an isolated feature known as a stack.
what are the effects of cliff collapse?
in st oswald bay east of durdle door 65ft of coastal path has fallen away, theres been no loss of life but its hard to predict where and when its gona happen. in torquay sue diamond agreed to pay £154,000 for a house by the sea. six days later the cliff collapsed taking much of the 1930s house with it. the house is now worth £3,500.