Low and high energy coasts and coastal sediment budget

Question 1

What do low energy coasts have?

Answer 1

Low wave energy

Rate of deposition exceeds rate of erosion - beaches and spits

Question 2

When can you find low energy coastlines?

Answer 2

Sheltered bays,
Inlets
Estuaries

Question 3

What do high energy coasts have?

Answer 3

High energy waves driven by strong, steady and prevailing winds
Rate of erosion is greater than deposition - cliffs, wave cut platforms, headlands

Question 4

Where does coastal sediment come from?

Answer 4

Streams and rivers (estuaries)
Cliff erosion (common on high energy coasts)
Offshore sandbanks
Biological origins (shells and coral fragments)

Question 5

What is a sediment cell?

Answer 5

Distinct area of coastline
Areas of coastline are separated from each other by boundaries like headlands
In theory it is a closed system
Vary in size from a cove to an entire coast

Question 6

What do coastal sediment budgets measure?

Answer 6

Balance between sediment addition and removal

Question 7

What must you require to measure the balance between sediment addition and removal?

Answer 7

The identification of sediment sources and sinks

Question 8

If the removal of sediment is greater than the addition of sediment what occurs?

Answer 8

The coast begins to recede

Question 9

If the addition of sediment is greater than the removal of sediment what occurs?

Answer 9

The coast begins to advance

Question 10

What is a sediment budget?

Answer 10

A balance between the addition and removal of sediment for a sediment cell

Question 11

Explain the concept of a sediment cell?

Answer 11

Closed system bounded by headlands
Within a cell there is erosion, transport and deposition
which occur over a long term cycle
Only input is erosion of the land or sea bed
There is little or no movement of sediment between cells.