COASTS Flashcards
WAVE HEIGHT
distance between crest and through
WAVELENTH
distance between 2 successive crests/ troughs
FREQUENCY
number of waves per minute
VELOCITY
speed of travelling wave
FETCH
distance travelled by a wave in open water
BACKWASH
water running back into sea from a wave
SWASH
water washed up by the beach by the wave
BEACH PROFILE
shape of a beach (always changing)
WAVES FORM
due to friction between waves and sea
HIGH PRESSURE AREAS OF A WAVE
through
LOW PRESSURE AREA OF A WAVE
crest
CORRASION
waves pick up beach material, hurl them against cliff & dislodges rock in cliff
ATTRITION
wave causes material that’s already been eroded from cliff to knock together
HYDRAULIC ACTION
wave hits cliff, pressure on air in cracks
wave retracts, pressure released quickly
rock loosened and breaks away
CORROSION
salts and other acids in seawater slowly remove rock in cliff by dissolving it
DYNAMIC EQUILIBRIUM
coastline is always changing
CONCORDANT COASTLINE
same geology, erodes at same speed
DISCONCORDANT COASTLINE
different types of rock, eroded differently
ATOLL REEF
roughly circular perched around oceanic volcano seamount and encircle a shallow central lagoon
FRINGING REEF
grows fairly close to shore with entirely shallow lagoon or none at all
BARRIER REEF
parallel to shore, separated from shore by a wide lagoon with deep portions
LAGOON
stretch of salt water seperated from sea by a reef or sea bank
WHAT IS A CORAL REEF
a structure built up from remains of living organisms/coral polyps etc
