sea level change Flashcards
what are the two types of sea level change?
eustatic and isostatic
what s eustatic change?
a global change in sea level resulting in an actual rise or fall in the level of the sea itself
what is isostatic change>
a local change in sea level resulting from the land rising or falling in relation to the sea
what is the typical sequence of sea level rise?
- climate get colder and water stored as ice eustatic fall
- weight of the ice on land cause it to sink this is isostatic
- climate gets warmer eustatic rise
- isostatic readjustment
what is isostatic readjustment?
when ice melts form the land and the land is lifted again
how are emergent features formed?
if isostatic movement is faster than eustatic
why is isostatic readjustment complicated?
affects difeferent places in different ways
northwest of british isles sinking whilst north west is rising
what are the features of submergence?
rias
fjords
dalmation coasts
what are rias?
drowned river valleys
what are fjords?
drowned glacial valley
how deep are fjords?
over 1000 metres
what are the characteristics of fjord
steep sides
u shaped
a shallower section by the mouth known as the threshold
why is the threshold made?
thought to be less glacial erosion when the ice comes in contact with the sea as it becomes thinner
what is different about fjords and rias to dalmatian coats?
dalmation coasts run parallel to the coast whereas
what are emergent features?
raised beaches
