The erosion of a headland is explored in more detailed below. If you've found the resources on this page useful please consider making a secure donation via PayPal to support the development of the site. The site is self-funded and your support is really appreciated. If you've found the resources on this site useful please consider making a secure donation via PayPal to support the development of the site. Erosion of a Headland Headlands are areas of more resistant rock that extend into the sea.
Erosion of a headland. Stage 1 in the formation of a headland Waves attack a weakness in the headland. Stage 2 in the formation of a headland A cave is formed.
Stage 3 in the formation of a headland Eventually, the cave erodes through the headland to form an arch. The image below shows an arch at Flamborough. As the headland becomes more exposed to the wind and waves the rate of its erosion increases.
When headlands erode they create distinct features such as caves, arches, stacks and stumps. The diagram below shows the sequence in the erosion of a headland. Stage 1 Waves attack a weakness in the headland. Stage 2 A cave is formed. Stage 3 Eventually the cave erodes through the headland to form an arch. Stage 4 The roof of the arch collapses leaving a column of rock called a stack. The net result of this over long periods of time is that the hard rock is left jutting out to sea as a headland, and the softer rock is eroded into curved sand filled bays.
A cliff is a vertical, near vertical or sloping wall of rock or sediment that borders the sea. They generally differ in their angle of slope because of their rock structure and geology, but the processes involved in their formation are the same. Marine erosion processes attack the foot of the cliff and cause the erosion at a wave cut notch. Waves can pound this area causing fragments to break off, and the water can also trap air in pore spaces, faults and crevices, compressing the air which in turn exerts pressure on the rock causing it to break off.
This process is known as hydraulic action. Another process that occurs is corrasion, where sediment and rocks in the sea water are hurled against the cliff face.
All three of these processes erode the wave cut notch at the base of the cliff undermining the whole structure of the cliff. These processes are variable and depend upon the fetch of the wave the distance it travels over open water , wind speed and how many storms there a year, but they are more or less continuous over long periods of time.
At the same time that the base of the cliff is being eroded, the cliff face and its structure are being weakened by sub aerial processes. Oxidation and carbonation are some of the chemical processes that can weaken the structure of the rock, and depending upon the climate physical processes such as freeze thaw and water layer weathering can take effect. A wave-cut platform is a wide gently-sloping surface found at the foot of a cliff.
A wave-cut platform is formed when the following occurs:. Caves, arches, stacks and stumps are erosional features that are commonly found on a headland. Erosional landforms The process of erosion can create different landforms along the coastline.
Headlands and bays Cliffs along the coastline do not erode at the same pace. Cliffs and wave-cut platforms Cliffs are shaped through erosion and weathering. A wave-cut platform is formed when the following occurs: The sea attacks the base of the cliff between the high and low water mark.
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