deep and narrow gap in cliff face = expands over a long period of time
formed by processes acting on a vertical fault or joint
erosion processes acting on resistant geology
define blowholes - created by erosion
deep caves recessed into cliff face that connects to top of cliff
allows water that enters by wavepounding to spray upwards
erosion processes acting on resistant geology
define headlands and bays - created by erosion
created where coast line is discordant
less resistant geology = erodes faster and retreats landward = creates shallow bay, wide beach and fine sediment.
more resistant geology = erodes slower, creating a headland = exposed to marine processes from all sides = increases erosion rate and narrows headland.
define wave cut platforms - created by erosion
flat intertidal surfaces of resistant rock
horizontal geological structure
resistant rock underlies a cliff face of less resistant rock
caves
arches
stacks
stumps
caves can exist anywhere with resistant geology
the rest can only exist after a cave has grown through a headland = narrow headland has higher chance of becoming an arch.
define caves - created by erosion
formed as wave energy impacts intertidal cliff face
formed on more resistant geology = less likely to collapse
define arch - created by erosion
when the cave penetrates to the other side of the headland
define stack - created by erosion
arch widens with erosion = eventually collapses by mass movement = leaves a stack