9. Sea Level Changes Flashcards
What is eustatic change?
Global change in sea level resulting from a rise or fall in the level of the sea itself
Eg due to the retreat of ice following a glacial period
What is isostatic change?
Local change in sea level resulting from land rising or falling relative to the sea
Eg tectonic movements
What features are formed by rising sea level?
Shingle beaches
Estuaries
Rias
Fjords
What features are formed by falling sea level?
Raised beaches and relict cliffs
Marine platform
What is a shingle beach?
Where river sediments previously deposited on the continental shelf were above sea level
Rising sea levels over the past 20,000 years have swept up the sediment and deposited it on present day coats
What is an estuary?
Drowned, shallow, lowland river valleys on upland coasts
Eg Humber River
What is a ria?
Drowned river valleys on upland coasts
Eg River Dart, Devon
What is a fjord?
Drowned glacial valley
Eg Milford Sound, New Zealand
What is raised beach?
Beaches and cliff lines elevated above sea level and exposed following deglaciation and the unloading of ice sheets from northern Britain
Eg Isle of Arran, Scotland
What is a marine platform?
Where an expanse of gently sloping, formerly submerged land has been exposed by uplift of the lowering of sea levels
What are Dalmatian coasts?
Similar to rias
But the rivers flow more parallel to the coast
Whereas the rivers of rias flow at right angles to the coast
Eg Croatia
