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What are the geographical processes of coastal erosion?

My topic is Coastal erosion & Beach replenishment and i'm doing the Bate Bay area (cronulla beach, wanda beach etc.) Please help :)

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1. * Hydraulic action - this is when air in cracks on the cliff face becomes compressed by the power of the waves striking the cliff face. As this happens the air inside the crack is compressed, putting a lot of pressure on the surrounding rock. The air then expands explosively, forcing out pieces of rock. Over time, the cliff face crack breaks causing a larger crack or cave to form. The rock from the cliff face which was removed falls to the bottom of the sea bed and is used for another two wave action (Attrition and Corrasion (Abrasion)). * Attrition - this is the when the sea grinds the rocks, and also the rock on the cliff, together, causing it to become smoother and reduced in size. As the sea rocks from side to side it moves the scree causing pieces of scree to collide with other pieces of scree thus causing them to become reduced in size and smoothed and rounded. As well as colliding with other pieces of scree the scree also collides with the cliff face base causing pieces of rock to be broken of the base of the cliff face contributing to this wave action and one more (Corrasion (Abrasion)). * Corrasion (Abrasion) - this is when the waves break on the cliff face pounding the cliff face slowly eroding it. Along with the cliff face being eroded by the power of the sea the sea also uses the scree from other wave actions. As the sea pounds the cliff faces it also uses the scree to batter and break off pieces of rock from higher up the cliff face which can be used for this same wave action or one other (Attrition). * Corrosion or solution - this is when the sea uses its low pH (anything below pH 7.0) to corrode away the rocks on the cliff face. Usually the only cliff faces to be greatly eroded in this manner would be limestone cliff faces as they have a high pH and would be easily eroded by a low pH. The rocking action of the sea also makes it easier for the sea to erode limestone cliff faces as the rocking action of the sea acts as the stirring motion in a chemistry experiment which helps to speed up a corrosive experiment. Factors that affect erosion rate: * Geological structure and lithology: hardness, height, fractures/faults * Wave climate: prevailing wave direction * Sub-aerial climate: weathering (frost, etc.), stress relief swelling/shrinkage * Water-level change: groundwater fluctuations, tidal range * Geomorphology * Weathering and transport slope processes * Slope hydrology * Vegetation * Cliff foot erosion * Cliff foot sediment accumulation * Resistance of cliff foot sediment to attrition and transport * Coastal land use * Resource extraction * Coastal management