Beaches Part3 Flashcards
What is a lagoon?
little or no fresh water influx and not receiving tidal circulations
General Characteristics of a lagoon?
1-elongated and parallel to coastline, separated from open marine enviro
2-do not have normal marine salinity
3-do not have rapid sediment supply
4-chemical properties vary considerably
5-distinct fauna and flora
6-most develop in low to mid latitudes
7-typically shallow, low energy with limited fetch
What kind of range of salinity?
Large ranging saline to hypersaline due to seasonal rain fall.
What is polyhaline?
a lagoon that displays great change in salinity from brackish to hypersaline
ex.lake reeve
What is hypersaline?
a lagoon that is continuely above normal marine concentrations
occur in semiarid and arid coastal zones
ex. lagunal madre
What causes most of the beach erosion in florida?
85% is caused tidal inlets
What are the dynamics of a tidal inlet?
highly dynamic and change rapidly and substantially
Symetrical inlet vs asymmetrical inlet?
both sides of inlet are similar
one side sticks out farther than the other
WHat makes up an ebb tidal delta?
Depositional Features: terminal lobe swash platform swash bar spit platform
What makes up a flood delta?
Erosional Features:
main channel
flood channel
marginal channel
What is the amount of water in and out of a bay called?
Bay tidal prism
What controls the size of a bay?
back shore slope
regional topography
sedimentation history
What controls the tidal rang with ebb and flood of a bay?
shoreline configuration
shelf width and bathymentry
character of amphidromic system
WHat are the characteristics of tide dominate?
straight and deep tidal channel with ebb and flood deltas and symmetrical
WHat are the characteristics of wave dominate?
meandering inlet with longshore barrier spit migration and asymmetrical. little ebb and flood delta
