Landforms by Erosion
Landforms by Erosion (erosion is the main process) * High-energy waves * Rocks that are easily eroded
1) Cliff and shore platforms
Point : A cliff is a high, steep rock face along the coast.
Explanation: A cliff is formed when waves repeatedly pound against a rocky coast
Elaboration: This weakens the rock, causing the lines of weakness to form in the rock face * Over time, the waves erode the coast to cut a notch along the lines of weakness. * The notch may be further eroded to form a cave * The overhanging part of the notch or cave eventually collapses with repeated pounding of the waves,
Statement: The part of the coast that is left forms a cliff
Elaboration: As a cliff continues to be eroded by waves, it retreats inland. Over time, a gently sloping or flat surface known as shore platform may develop at the base of the cliff. Some additional details : Costal processes continue to act on the cliff and shore platform, depending on the tides.
For example: during high tide—the water extends up to the coast and covers the shore platform. Hence, waves will continue to erode the cliff at its base. during low tide-- the shore platform lies exposed above the water. Waves tend to deposit sediments onto the shore platform because its gentle slope causes the waves to lose their energy due to friction with the shallow seabed.
Example : Cliff--White cliffs in Dover, Southern England Wave-cut platform—Victoria island coast, Hong Kong
2) Headlands and Bays
Definition: A headland is a protruding area along a coast made up of more resistant rocks A bay is an area of less resistant rocks where the coast curves inwards
Point: Some coasts are made up of rocks with different resistance to erosion. Explanation: The less resistant rocks, such as chalk erode faster, compared to the more resistant rocks like granite.
Elaboration: The different rates of erosion of the rocks along the coast produce the
1) Cliff and shore platforms
Point : A cliff is a high, steep rock face along the coast.
Explanation: A cliff is formed when waves repeatedly pound against a rocky coast
Elaboration: This weakens the rock, causing the lines of weakness to form in the rock face * Over time, the waves erode the coast to cut a notch along the lines of weakness. * The notch may be further eroded to form a cave * The overhanging part of the notch or cave eventually collapses with repeated pounding of the waves,
Statement: The part of the coast that is left forms a cliff
Elaboration: As a cliff continues to be eroded by waves, it retreats inland. Over time, a gently sloping or flat surface known as shore platform may develop at the base of the cliff. Some additional details : Costal processes continue to act on the cliff and shore platform, depending on the tides.
For example: during high tide—the water extends up to the coast and covers the shore platform. Hence, waves will continue to erode the cliff at its base. during low tide-- the shore platform lies exposed above the water. Waves tend to deposit sediments onto the shore platform because its gentle slope causes the waves to lose their energy due to friction with the shallow seabed.
Example : Cliff--White cliffs in Dover, Southern England Wave-cut platform—Victoria island coast, Hong Kong
2) Headlands and Bays
Definition: A headland is a protruding area along a coast made up of more resistant rocks A bay is an area of less resistant rocks where the coast curves inwards
Point: Some coasts are made up of rocks with different resistance to erosion. Explanation: The less resistant rocks, such as chalk erode faster, compared to the more resistant rocks like granite.
Elaboration: The different rates of erosion of the rocks along the coast produce the