physical environment

Question 1

what is hydraulic action?

Answer 1

This is when the power of the waves comes crashing against the cliffs, squeezing the air in its cracks, which make the cracks wider and longer until pieces of rock break off.

Question 2

what is corrasion?

Answer 2

This is when the sand and pebbles are thrown against the cliff, causing pieces of rocks to fall off.

Question 3

what is solution?

Answer 3

This happens as the salt and other chemicals in the sea slowly dissolve the minerals in the rocks causing them to break up.

Question 4

what is the process of deposition?

Answer 4

Longshore drift is the process through which material is moved along a beach. Waves approach the beach at an angle, waves break and the swash carries material up the beach at the same angle as the wave. The backwash, and any material carried by it, returns by the shortest route at right angles to the beach. This creates a zigzag pattern of transportation.

Question 5

(erosional feature)
how is a wave cut notch/platform made?

Answer 5

A Wave-cut platform forms when a notch is cut into the base of a cliff by waves. Overtime the notch gets larger and deeper mainly due to hydraulic action. Eventually the unsupported rock above will collapse into the sea. The sea will remove this debris, and the process repeats itself. Eventually a wave-cut platform will be left in front of the cliff.

Question 6

(erosional feature)
how do headlands and bays form?

Answer 6

Headlands and bays form along coasts that are made of alternative bands of hard
(resistant) and soft (less resistant) rocks. The waves erode the softer rocks (clay) more quickly to form bays and the harder rocks (chalk) are eroded more slowly and left jutting into the sea to form headlands. Overtime the bays will become more sheltered and sandy beaches will form.

Question 7

(erosional feature)
what is the formation of: caves, arch, stack and stump?

Answer 7

Waves crash into headlands eroding weaker parts such as cracks (joints or faults). The cracks are eroded by 3 different processes corrasion, hydraulic action and solution. The cracks get larger, deeper and wider, developing into a cave. Overtime, the horizontal erosion of a cave may cut through the headland to the other side to form an arch. Very occasionally a blow hole will be created within a cave where vertical erosion has taken place. Further erosion widens the walls of the arch leaving less support for the roof, leading to its collapse and to the formation of a stack isolated from the cliff. The stack will be eroded to form a needle. The needle will be eroded, collapse and become a stump.

Question 8

(depositional feature)
how are beaches fromed?

Answer 8

Beaches are made up of soil or rock fragments that have been eroded from cliffs by the waves. These fragments are then broken into smaller pieces and rounded off. The eroded material is then deposited where waves have little energy forming a beach. A typical beach
has sorted deposits, the largest deposits are found at the back of the beach and the
smallest next to the sea. The largest beaches are usually found in bays, where the waves are generally weak.

Question 9

(depositional feature)
what is the formation of: sandspit, sand bar and tombolo?

Answer 9

A spit forms when beach material is transported along the coast by longshore drift* A ridge of sand builds up and outwards forming a spit. If the spit extends across the mouth of a bay it can join up with a beach on the other side forming a sand bar. This straightens the coastline and encloses a lagoon on the landward side of the bar. Along some coastlines a
sand spit may grow outwards into open water and reach an island forming a Tombolo.