costal sediment budgets Flashcards
costal sediment comes from what sources?
streams or rivers flowing into the sea
estuaries
cliff erosion
offshore sand banks.
what is happening with the source of sediment which leads to the build up of certain depositional features around the British coast?
Is in dispute.
research has suggested what about sediment?
sediment movements occur in distinct areas or sediment cells, within which inputs and outputs are balanced.
what has been identified along the coastline of England and wales?
11 of these sediment cells have been identified, sediment cells can be regarded as closed systems from which nothing is gained or lost.
What is it easy for fine sediments to do?
To find their way around headlands and into neighbouring cells.
sediment cells vary in what?
size.
The larger ones are divided into what?
into smaller sections to allow closer study and management.
what is an example of a sub-cell?
Flamborough head and the Humber Estuary on the east coast of England.
what ha to happen for a sandy beach or muddy shore line to exist?
sediment has had to come from somewhere and the combination of wave, current and tide action to be such that material remains there.
This introduces the coastal sediment budget.
what is the coastal sediment budget?
The coastal sediment budget is best thought of as being similar to a bank account, defined as balance between sediment being removed and added to the coastal system.
what happens when more material is added to the cell than is removed?
causes a net accretion of material.
The net accretion of material results in what?
A positive budget, or a surplus of sediment.
A positive budget does what to the shoreline?
shoreline builds towards the sea.
what happens when more material is removed from the cell than is added?
causes a negative budget or a deflect in sediment supply.
A negative budget does what do the shoreline?
shoreline retreats landward.
