Deposition occurs when waves wash sand, rock and pebbles from the sea floor to the beach. In this case, deposition is likely to occur on the beaches of Terrigal and Wamberal if the waves enter shallow water or a sheltered area, if there is little wind and a good supply of material. Rocks have been deposited in a flat rock formation that spreads out for about 100 metres. Scientists say that the rocks and pebbles were located in that area many years ago by the waves of a severe storm.
Erosion is the process of eroding or being eroded by wind, water, or other natural agents. Due to The Skillion being made up of sandstone, the constant water of the waves hitting the cliff face over and over again everyday has made the sandstone erode into the water. Where most of the cliff face is lumpy and bumpy there is a distinct large indentation in the rock. This is what causes the chunks of rock that tumble off the cliff face. Erosion also occurs on the beaches of Terrigal / Wamberal when high tide comes in and it takes away all the shape of the sand and sand dunes. This affects the people living on the coastline.
Longshore drift is the movement of material along a coast by waves which approach at an angle to the shore but recede directly away from it. The community have tried to plant vegetation in the sand dunes to attempt to keep them together and stop collapsing due to the high tides. The longshore drift nearly always ruins those plans and drags all the vegetation up the beach into what is called the ‘swash’. The swash is known as a turbulent layer of water that washes up on the beach after an incoming wave has broken. This process affects people living along the coastline of Terrigal and Wamberal.
Transportation occurs when waves carry materials along at an angle along the coast line. If a house was to collapse due to the long shore drift or erosion, then the waves would move the materials further up the beach. This has happened to houses on Terrigal and Wamberal beach.