Coasts: Coastal Terminology, Land Forms And Processes Flashcards

Question

What is hydrolysis?

Answer 1

When the acidic water reacts or combines with minerals in the rock to create plates and dissolvable salts. This itself degrade the rock, thus making it more susceptible to further degradation

Answer 2

Where animals and plants wear rocks away. Thin plant roots grow into small cracks, water running through decayed vegetation becomes acidic, animals burrow into cliffs, marine organisms burrow or secrete acids

Answer 3

1. Hydraulic power 2. Wave Quarrying 3. Abrasion 4. Attrition 5. Corrosion

Answer 4

The action of waves breaking against unconsolidated material such as sand and gravels. This can exert enormous pressure upon a rock surface thus weakening it. Sometimes referred to as wave pounding

Answer 5

The sheer force of the water as it crashes against a coastline is called wave quarrying. When a wave advances air can be trapped and compressed, when the waiver retreats the compressed air expands. This continuous process can weaken joints and cause cracks in the cliff and cause pieces of rock to break off

Answer 6

The material the sea has picked up also wears away rock faces. Sand shingle and boulders hold against the cliff line will do enormous damage. This is also apparent on inter-tidal rock platforms where sediment is drawn back and forth

Answer 7

The rocks in the sea which carry out abrasion are slowly worn down into smaller and more rounded pieces

Answer 8

Include the dissolving of calcium based rocks: when seawater dissolves certain types of rock

Answer 9

Refers to the characteristics of rocks, especially resistance to erosion and permeability. Very resistant rocks such as grit and to a lesser extent chalk tend to be eroded less than weak materials such as clay. Some rocks like limestone are well jointed which means that the sea can penetrate a long line of weakness, making them more vulnerable to erosion. Variation in the rates of which rocks were away is also known as differential erosion. The structure and variation of rocks also affects the coastline: concordant - parallel to the coastline, and discordant - running at right angles to the coastline

Answer 10

The downward movement or sliding of material under the influence of gravity. There are five types: rock Falls, landslides, mud flows, landslips (slumps) and soil creep

Answer 11

A rockfall involves the sudden collapse or breaking away of individual rock fragments (or a block of rock) at a cliff face. They are most commonly associated with steep or vertical cliffs in heavily jointed and often quite resistant rock. A rockfall is often triggered by mechanical weathering (particularly freeze-thaw) or an earthquake. Once broken away from the source, rocks fall or bounce down the slope to form scree (also known as talus) at the foot of the slope. Scree often forms a temporary store within the coastal system, with material gradually being removed and transported elsewhere by the sea. When this occurs the scree forms an input into the sediment cell.

Answer 12

A landslip or slump differs from a landslide in that its slide surface is curved rather than flat. Landslips commonly occur in weak and unconsolidated clays and sands, often when permeable rock overlies impermeable rock, which causes a build-up of pore water pressure. Landslips or slumps are characterised by a sharp break of slope and the formation of a scar. Multiple landslips can result in a terraced appearance on the cliff face.

Answer 13

As the name implies, soil creep is an extremely slow form of movement of individual soil particles downhill. The precise mechanism of movement often involves particles rising towards the ground surface due to wetting or freezing and then returning vertically to the surface in response to gravity as the soil dries out or thaws. This zigzag movement is similar to that of longshore drift. Soil creep cannot be seen operation but its action can be implied by the formation of shallow terracettes, the build-up of soil on the upslope side of walls and the bending of tree trunks

Answer 14

A mudflow involves earth and mudflow are found in unconsolidated or weak bedrock such as clay, often after heavy rainfall gets trapped within the rock, increasing pore water pressure, which forces rock particles apart and leads to slope failure. Fore water pressure is a form of energy within the slope system and it is an extremely important factor in determining sore. Mudflows are often sudden and fast-flowing so can represent a significant natural hazard.

Answer 15

A landslide involves a block of rock moving very rapidly downhill along a planar surface (a slide plane), often a bedding plane that is roughly parallel to the ground surface. Unlike a mudflow, where the moving material becomes mixed, the moving block of material in a landslide remains largely intact. Landslides are frequently triggered by earthquakes or very heavy rainfall, when the slip surface becomes lubricated and friction is reduced. Landslides tend to be very rapid and pose a considerable threat to people and property. In 1993, 60m of cliff slid onto the beach near Scarborough in North Yorkshire, taking with it part of the Holbeck Hall Hotel.

Answer 16

1. Eroded materials from the cliffs are on the beach 2. The waves from the sea come onto the beach at an angle and move the material up the beach 3. The waves then move back down the beach in a straight direction due to gravity

Answer 17

The rolling of large molecules along the sea floor by the waves

Answer 18

The bouncing of slightly lighter material along the sea floor

Answer 19

Small particles of material carried by the water

Answer 20

Material is dissolved and carried by the water

Answer 21

Generally be in a low energy environment

Answer 22

Generally be in a high energy environment

Answer 23

A spit that has a hooked end as a result of a change in prevailing wind direction

Answer 24

Forms in the same way as a spit (longshore drift) but across a body of water, separating it from the ocean

Answer 25

Bar that connects to the mainland of an island

Answer 26

A type of dune system where an area of sand has been formed by wave and tidal action parallel to the mainland coast. If a barrier beach becomes separated from the mainland, it becomes a barrier island

Answer 27

Waves repeatedly deposit sediment parallel to the shoreline

Answer 28

The evolution of plant communities at a site over time - from pioneer species to climax vegetation

Answer 29

- At each stage of the succession the plant community alters the soil and microclimate, allowing the establishment of another group or species → one community of plants is replaced by another as the succession develops - Eventually, a climax community is reached → vegetation is in a state of equilibrium with the environment and there is no further influx of new species.

Answer 30

→ plentiful supply of sand → strong winds to transport sand particles through saltation. → an obstacle to trap the sand eg a plant. Can also be man made.

Answer 31

new dunes on foreshore • seeds blown in by the wind or washed in by the sea. • rooting conditions are poor due to drought, strong wind, salty sea water immersion and alkaline conditions created by seashells. • wind moves the sand allowing rainwater to soak through rapidly

Answer 32

• plants trap sand and grow with it, binding the sand together within their roots • humus created by decaying pioneer plants creates more fertile growing conditions - soil becomes less alkaline as pioneer plants grow and trap rainwater. • less hardly plants can grow and start to outcompete pioneer plants. • as plants colonise the dunes, the sand disappears and the dune changes colour - from yellow to grey

Answer 33

• taller plants (e.g trees) and more complex species (eg moorland heathers) can now grow • plants from earlier stages die out because of competition. • when water table reaches or near the surface, dune slacks can occur where specially adapted water-tolerant plants can grow.

Coasts: Coastal Terminology, Land Forms And Processes Flashcards

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