Coastal Landforms

What are the 3 factors of coastal erosion

Weather and climate / Underlying Geology / Humans Activity

How is a Cliff formed

The base of the cliff is eroded (e.g hydraulic abrasion) / a notch forms / as the base weakens, the upperpart can fall off by weathering (freeze - thaw) / back wash of a wave erodes it even more

How is a Cave formed

A notch or fault in the headland appears and repetitive and continuous erosion, for example hydraulic action, wears away and breaks apart the fault. The fault grows wider as sediment and rock is transported away which leave a cavernous hold in the headland

How is an Arch formed

Same as a cave, however the crack continues until the other end, forming the arch

How is a Stack formed

Parts of the rock are weathered of an arch, which therefore fall and form the Stack

How is a Stump formed

Continued erosion of a stack

How is a Beach formed

Erosion from elsewhere provides sediment / waves transport this material along the coast via longshore drift / sediment is then deposited / has a stronger swash than backwash

How is a Spit formed

Sediment transported via longshore drift / coastline changes direction / deposited into the sea / material added over time / often curves at the end due to wind

How is a Bar formed

Sedimented moved by longshore drift / a spit forms across a bay / continued deposition until the spit connects the two sides / traps water to form a lagoon

How is a Tombolo formed

Waves bend around the island, therefore causing longshore drift / a ridge is formed / ridge links the island to the mainland

How is a Sand Dune Formed

Dry sand is supplied from beach / Wind blows sand inland / wind meets an obstacle it loses energy / the sand is deposited making small mounds / dunes form from these mounds