Estuaries And Coasts Flashcards
1
Q
Origin of estuaries?
A
drowned river valleys
bar built estuaries
fjord
tectonic estuary
2
Q
Salt wedge estuary?
A
fresh water flows out at surface salt water intrudes at depth sharply tilted interface one way mixing (entrainment) net seawards flow - almost all fresh water
3
Q
Partially mixed estuary?
A
surface outflow exceeds feshwater inflow increased tidal mixing tilted density contours salt inflow due to advection and diffusion rapid exchange of water
4
Q
Well mixed estuary?
A
even greater tidal mixing reduced river flow salinity becomes uniform with depth little or no inward transfer of seawater slow net seaward flow at all depths
5
Q
Fjord estuary?
A
river flow remains at surface - little mixing
deep basin with entrance sill, moderate river flow and little tide
6
Q
Inverse estuaries?
A
Salinity increases up the estaury
7
Q
Beach definition?
A
active region between depth of initial sediment movement and maximum run up limit
8
Q
Calm conditions?
A
low waves
weak undertow
accretion dominant
formation of berm
9
Q
Energetic conditions?
A
high waves
strong undertow
formation of sand bar
10
Q
Coastal dunes?
A
formed from windblown sand
