coastal systems -landforms of sea level change Flashcards
what are the 2 types of landforms created through sea level chnage?
.emergent
.submergent
where do emergent landforms develop?
.where areas experience a fall in sea level eg -raised beaches and marine platforms
where do raised beaches form?
.form where the sea level drops relative to the land so what was a beach becomes stranded above the high water mark
what is an example of a raised beach?
.isle of arran in Scotland
what are raised beaches subject to?
.vegetation succession once above the high tide level and therefore may appear as flat, grassy terraces
.other marine features such as cliffs and cliff profile features like caves may also be left above the high tide level in which case, they are called relict features
what is an example of a relict feature?
.kings cave on arran in Scotland
why are raised beaches unusual?
.because they don’t occur everywhere as not everywhere was covered in ice and you only get it in places with isostatic rebound
what are marine platforms like?
.left exposed above the level of the current wave cut platform, are often less visible as they may be covered in beach sediment from the current beach
why do submergent landforms occur?
.as a result of a combination of eustatic or isostatic change
where do submergent landforms develop?
.where areas experience a rise in sea level eg -rias, fjords and dalmation coast
what are rias?
.flooded river mouths/valleys
where do rias form?
.where the sea level rises relative to the land, river valleys flood and appear as coastal inlets with relatively steep coastlines where the old valley sides are and the floodplain has been flooded by the sea
what is an example of a ria?
.the mouth of the river exe at exmouth
what are fjords?
.flooded glacial valleys
.steep valley sides
.fairly straight and narrow
.deeper the further inland they reach
.u-shaped cross section
how do fjords form?
.fjords form from a glacial trough which bulldozes land out of the way
.once the ice melts, it leaves a pile of rock which the flowing ice had moved
why are fjords much deeper than rias?
.because sea level was a lot lower -100m in the glacial period
what is an example of a fjord?
.sognefjord in Norway
what are dalmation coastlines?
.series of offshore island running parallel to the coastline
where do dalmation coasts occur?
.where river systems once ran parallel to the coast (generally due to concordat geology) are flooded resulting in a series of long islands which would once have been the hills along the valley sides parallel to the coastline
what is an example of a dalmation coast?
.dalmatian coast in Croatia
