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Describe the key stages of landform change in the formation of a stump. Referring to process of weathering and erosion in your answer. (6/8 marks)

At a high energy coastline, with resistant coastal geology, a crack may form in the cliff at an area of weakness in the rock. As wave energy causes erosion through hydraulic action, as air is forced into cracks causing in high pressure which erodes the rock, and chemical weathering forming a weak carbonic acid, both increasing the size of the crack. Overtime, the crack will increase in size, forming a cave. The cave will be further eroded through hydraulic action and chemical weathering . Also, abrasion will occur, as wave energy will propel stones and rocks at the face, eroding the cave further into the headland. Eventually, the cave will be eroded through to the other side, thus, an arch has formed. The base of which will experience the above weathering and erosional processes, whilst the roof will be exposed to biological weathering, from vegetations' roots breaking down the rock, and freeze-thaw weathering, which occurs due to ice expanding in cracks and faults in the rock exerting pressure, so when it thaws, the rock to weakens. Overtime, due to the previous processes, the roof of the arch will weaken, to a point which it cannot hold its own weight, and so gravity will cause the roof to collapse, thus forming a stack. The stack will, over time, collapse forming a stump, due to the base being exposed to high levels of erosion through hydraulic action and abrasion.