AQA AS Geography Coasts: Coastal Processes

HideShow resource information
  • Created by: LucySPG
  • Created on: 22-08-13 20:21
Preview of AQA AS Geography Coasts: Coastal Processes

First 142 words of the document:

Coastal Processes
How Waves Erode the Coastline
Abrasion/ Corrasion Bits of rock and sediment transported by the
waves smash and grind against rocks and
cliffs, breaking bits off and smoothing
surfaces
Hydraulic Action Cliffs and rocks contain many lines of
weakness in the form of joints and cracks.
A parcel of air can become trapped /
compressed in these cracks when water is
thrown against it.
The increase in pressure leads to a
weakening / cracking of the rock
Quarrying The energy of a wave as it breaks against a
cliff is enough to detach bits of rock
Corrosion / Solution Soluble rocks get gradually dissolved by sea
water
Attrition Bits of rock in the water smash against each
other and break into smaller bits

Other pages in this set

Page 2

Preview of page 2

Here's a taster:

Subaeriel Weathering
Subaeriel weathering describes coastal processes that are not linked to the action of
the sea.
All slopes are subject to constant change. Some movements are slow whereas others are
rapid.
For these mass movements to occur, the underlying rocks must be weakened by the
processes of subaeriel weathering.
Most rocks are formed at great depth at high temperatures and/or great pressures and
often in conditions devoid of water or oxygen.…read more

Page 3

Preview of page 3

Here's a taster:

Chemical Weathering
Chemical weathering involves decomposition resulting from chemical change. Typically,
rock-forming minerals break down releasing elements to produce new minerals
that are more stable in the new conditions at the earth's surface.
Some are soluble whereas others form clays which are weaker minerals than the ones they
replace.
Chemical processes dominate in warmer, moist climates associated with good vegetation
cover and they tend to operate to a greater depth than physical weathering processes.…read more

Page 4

Preview of page 4

Here's a taster:

Mass Movements
Weathered rocks exposed in coastal zones are susceptible to mass movements.
Soil Creep The slowest form of mass movement.
Propagated by three main mechanisms.
Raindrop impact in intense storms may cause a splash of soil particles.
Those particles that fall on the downslope side fall further, resulting in
net downslope movement.
Wet periods add additional moisture to soil particles which swell upon
wetting, expand and fall slightly downhill under gravity when the soil
dries.…read more

Page 5

Preview of page 5

Here's a taster:

Biological Weathering
Biological weathering refers to weathering resulting from organic agents. These may be tree
roots growing into and physically widening joints, or animals burrowing.…read more

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all resources »