These terms are the bare minimum vocabulary you should be able to use and understand when sitting the examination. You are free to download this page for your own educational use.
- Arch
- When caves, which have developed on either side of a
headland, join together they form a natural arch.
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- Attrition
- The process whereby rock particles wear down
through collisions with other rock particles. This often occurs when
pebbles are thrown against cliffs, boulders or other pebbles, causing
them to shatter and break.
- Backwash
- Water moves up a beach as a wave breaks. This is
called the swash. The return movement of the water, back
down the beach, is called the backwash.
- Bar
- A bar is very similar to a spit. It
is a ridge of sand or shingle which forms across the mouth of a river,
the entrance to a bay or harbour. It is usually parallel to the coast.
- Bay
- A wide indentation into the land by the sea,
protected on each side by a headland. The water in a bay is usually
relatively shallow; the wave action less strong than at the headlands.
- Bay-bar
- A bar across the entrance of a bay.
- Bay-head beach
- Bay head beaches develop at the head, or inner
most part, of a bay. In this area wave action is usually not very strong
and deposition occurs. The beach will not extend to the headlands since
erosion from waves increases strongly towards the headlands and deeper
water.
- Beach
- A gently sloping deposit of sand, pebbles or mud,
deposited along the coast.
- Blow hole
- A blow hole is formed when a joint between a sea
cave and the land surface above the cave becomes enlarged and air can
pass through it. As water flows into the cave, air is expelled through
the pipe like joint, sometimes producing an impressive blast of air or
spray which appears to emanate from the ground.
- Cave
- A weakness, such as a joint, is enlarged by wave
action, finally creating a cylindrical tunnel which follows the line of
weakness. Caves developing back to back may give rise to arches
and stacks.
- Cliff
- A steep, and usually high, rock face found at the
edge of the land where it meets the sea. Cliffs can be formed from most
rocks, height generally increasing with hardness of rock.
- Cliff Line
- The margin of the land. The cliff line is
identical to the coastline, but consists of cliffs rather
than lower features such as dunes and beaches.
- Coastline
- The margin of the land. Where the margin consists
of cliffs, it is known as the Cliff line
- Constructive wave
- When waves break at a rate of ten or less per
minute each wave is able to run up the beach and drain back again
before the next wave arrives. The swash
is more powerful than the backwash so deposition can
occur.
- Corrasive action
- This is a form of wave erosion. Pebbles, boulders
and rocks are thrown against the cliff face by breaking waves. This
causes undercutting of the cliff and leads to the breakup of both the
cliff and the objects being thrown against it.
- Destructive wave
- When waves break at a rate of more than ten per
minute each wave is able to run up the beach but unable to drain back
again before the next wave arrives. Thus the backwash
of the previous wave interferes with the swash, reducing
it's efficiency. Such waves remove material from a beach and are
destructive.
- Emerged coast
- Coastal areas which have become raised above
current sea level. The cause is believed to be isostatic
adjustment.
- Estuary
- The mouth of a river where fresh water and sea
water mix, and tides have an effect. Estuaries are often to be found on
submerged coastlines, where a river valley has been
flooded by the sea. See ria.
- Fetch
- This distance of open water over which the wind
can blow and form waves.
- Fiord Coast
- When a glaciated coast, with deep valleys,
becomes flooded by the sea, the valleys are known as fiords. These
inlets are typically steep sided and deep.
- Headland
- Areas of harder rocks tend to resist the erosive
powers of the sea. The resulting area of land, jutting out into the sea,
is a headland. Bays are to be found between headlands.
- Hydraulic action
- When a wave breaks against a cliff it causes air
,trapped within cracks, to suddenly become compressed. As the water
retreats the air is allowed to expand, often explosively. Repeated
expansion and contraction of the cracks leads to the break up of the
surrounding rock.
- Lagoon
- When a spit extends across the
mouth of a river, to the extent that it causes the river to become
diverted along the coast, an area of water is created separated from the
sea by a narrow strip of land. This is a lagoon.
- Load
- Solid matter carried by water, including material
in solution, material suspended in the water, and larger material moved
along the water / ground interface.
- Longitudinal Coast
- These occur when valleys parallel to the coast
become flooded by the sea. As the land becomes submerged, the ridges of
land between the valleys become chains of islands parallel to the new
coast. The area of water between the island chains are sometimes
referred to as sounds.
- Longshore Drift
- When waves break on to a beach at an angle,
material is pushed up the beach at an angle by the swash, but pulled
back down the beach by the backwash at ninety degrees to the coast. In
consequence, material is slowly moved along the coast, in the direction
of the waves.
- Mud Flats
- Gently sloping coasts where fine sediments can
settle, perhaps together with river sediments, can allow the build up of
mud as a sheet known as a mudflat. Plants able to withstand salt water
will often colonise the area. In tropical areas this may lead to the
formation of mangrove swamps.
- Ria
- When a non-glaciated highland coast becomes
submerged, the valleys fill with sea water. As the area becomes flooded
the coast becomes indented and higher parts of the surrounding land may
become islands. Plymouth Sound and Southampton Water are examples of
rias in the United Kingdom.
- Sound
- Valleys flooded due to submergence under the sea
along a longitudinal coast are sometimes called Sounds.
- Spit
- Longshore Drift transports material along the
coast. When the mouth of a river, or an indented area, is encountered
material starts to be deposited. The deposition begins where the coast
changes direction and extends down coast in the direction of longshore
drift. The result is a narrow ridge of material ( sand or pebbles )
attached to the mainland at one end and terminating in the sea. The spit
may extend sufficiently to form a lagoon.
- Stack
- When a natural arch collapses, the
remaining upright sections form stacks, isolated rocks sticking up out
of the sea.
- Storm beach
- A ridge of material to the landward side of the
normal beach. During storm conditions the waves may have sufficient
power to throw material beyond the usual range ( between high and low
water marks ). Such material will remain in place for a considerable
time, being added to by subsequent violent storms.
- Submerged coast
- Coastal areas which have become lowered below
current sea level. The cause is almost always a rise in sea level in
consequence of ice melting since the last ice age.
- Swash
- The movement of water in a breaking wave as it
moves up the beach.
- Tides
- The daily movements of the sea as it covers and
exposes the area betweeFebruary 24, 2006ult of lunar activity, and to a much lesser degree, winds and
atmospheric pressure.
- Tombolo
- A bar linking an island to the
mainland.
- Undertow
- A current taking water away from the beach and
out into deeper water. The undertow prevents the build up of water from
breaking waves along the coast.
- Wave-cut Platform
- As cliffs become eroded down to beach level they
appear to migrate inland. The remains of the former cliffs form a flat
rock platform. This is known as a wave cut platform.
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