DL - Key Terms

landform

landform

a natural, recognisable feature of the Earth's surface

ice age

a glacial episode characterised by lower than average global temperatures and during which ice covers more of the Earth's surface

glacial processes

processes resulting from the action of ice, often in the form of glaciers or other landforms but can also involve the cold temperatures associated with glacial periods

Geomorphic processes

processes which result in a change in the shape of the Earth; from 'geo' meaning the earth and 'morph' meaning to change shape

igneous

when referring to rocks, this means rocks formed within the interior of the earth, and shaped by heat

sedimentary

rocks that have been produced from layers of sediment, usually at the bottom of the sea

metamorphic

rocks that have been changed as a result of heat and pressure being applied to them over long periods of time

impermeable

a surface or substance that doesnt allow water to pass through it

permeable

a surface or substance that does allow water to pass through it

weathering

the disintegration or decomposition of material in situ, by physical, chemical or biological processes

erosion

processes by which rock, sand, and soil are broken down and carried away

mass movement

the downslope movement of material due to gravity

rotational slump

the downslope movement of material along a curved slip plane

rock slide

the downslope movement of material along a straight slip plane

wave-cut notch

an erosional landform undercutting the base of a cliff between low and high water marks

hydraulic action

an erosive process which involves the pressure of water hitting a surface, compressing air into any cavities which exist and resulting in the removal of rock fragments over time

solution

the dissolving of soluble materials by acidic water

attrition

erosion of material as it knocks together

swash

The movement of water up the beach following the breaking of a wave on the coastline

backwash

The movement of water from a broken wave as it moves down the beach

transport

the movement of material by a range of processes

longshore drift

The movement of sediments along a stretch of coastline as a result of the wind and swash approaching the beach at an angle

deposition

the process by which sediment being transported is laid down

headland

an area of land that extends out into the sea, usually higher than the surrounding land; also called a point

bay

the area between two headlands which has been eroded at a faster rate, usually lower and often contains a beach

cave

the extended cracks and hollows at the base of a cliff

arch

an erosional landform where a cave has been eroded straight through a headland

stack

a coastal feature that results from erosion; a section of the headland that has become separated from the mainland and stands as a pillar of rock

joint

a vertical crack within a rock, such as limestone, which result from the natural shrinking of the rock over time as it was formed; these may form weaknesses allowing water to penetrate the rock

bedding plane

within a sedimentary rock, these represent the points where layers of sediment accumulates; they may later form horizontal weaknesses within the rock along which water may penetrate

stump

a coastal feature that results from the collapse of a stack to form a protrusion of rock close to the sea surface

wave-cut platform

a flat area along the base of a cliff produced by the retreat of the cliff as a result of erosive processes.

spit

a depositional landform formed at a change in direction of the coastline, due to longshore drift

abrasion

particles being carried by the river water or sea waves are thrown against the river banks or coastline

traction

The pushing or rolling of large sediment along a river or sea bed

saltation

the hopping or bouncing of sediment along the river or sea bed

suspension

the process by which small sediment is carried along by river water or waves

solution transport

the transport process by which material is dissolved in

discharge

The amount of water passing a given point in a river per unit of time; usually measured in cubic metres per second or CUMECS

v-shaped valley

an erosional landform with steeply sloping straight sides usually found in the upper course of a river valley

waterfall

a steep fall of water where its course crosses between different rock types, resulting in different rates of erosion

plunge pool

a pool formed at the base of a waterfall

gorge

a narrow passage formed as a waterfall erodes backwards

floodplain

the flat area of land either side of a river channel forming the valley floor, which may be flooded

levee

raised banks along a river that help to reduce the risk of flooding

meander

a sinuous bend in a river that results from the flow of water along it

ox-bow lake

a horse shoe-shaped lake that forms when a meander is separated (cut off) from the main river channel as a result of erosion