Beach glossary

Explanation of terms


Field NameDefinition
BarrierThe long term accumulation of marine and aeolian (wind-blown) sediments at and behind the beach, includes the beach and dunes.
Barrier islandA usually elongate, shore parallel barrier separated from the mainland by a lagoon and inlets.
Backbarrier typeThe nature of the terrain behind the barrier: 0 = bedrock; 1 = lagoon; 2 = swamp.
BeachUnique identifier used to join tables, not for purpose of display.
Beach KeyThe Beach Number used to identify beaches in ABSAMP.
Beach plus ridged sand flats Intertidal surface has shore parallel, possibly sinuous, low (<10 cm), equally spaced (~80 m), sand ridges.
Beach plus sand flat Intertidal surface is essentially flat and featureless apart from small ripples & drainage.
Beach plus tidal flats Intertidal surface is imprinted with tidal channel drainage and channels and may be composed of sand and/or mud.
Beach state refers to the state of the beach within each beach type as defined by the dimensionless fall velocity (omega=Hb/WsT) there are six wave dominated beaches (D, LBT, RBB, TBR, LTT & R) three tide modified beaches (R+LTT, R+LTR (rips), UD) Four tide-dominated beaches: (R+RSF, R+SF, R+TSF, R+TMF) two beaches fronted by rock/reef flats (R+rock flats, R+reef flats).
Beach state type1 = Primary refers to the dominant beach state along the beach; 2 = Secondary refers to the secondary beach type along part of the beach, which may or may not be present; 0 = outer refers to an outer bar (if present) the beach state always refers to the inner bar (by default).
Beach typerefers to the four types of beaches: wave-dominated, tide-modified and tide-dominate beaches as defined by the relative tide range (RTR=TR/Hb) together with beaches fronted by rock/reef flats.
Bedrock reef Intertidal bedrock reef located in front of beach.
BSC CodeBeach State / Beach Type code.
BSC DescDescription of Beach State / Beach Type
Carbonate contentPercentage of sediment composed of calcium carbonate, usually shell and/or coral fragments.
Coral Reef Intertidal coral reef located in front of beach.
Details General comments of the feature on this beach.
Drainage Refers to any well-defined watercourse across or adjacent to the beach. May be a freshwater stream, tidal creek, inlet or river.
Drainage location At what location does the drainage cross the beach: 1 = north (end of beach); 2 = east; 3 = south; 4 = west; 5 = centre.
Drainage type1 = tidal creek; 2 = upland stream; 3 = river.
EmbaymentisationThe chord of the beach divided by the arc. A measure of beach exposure.
Estuary maturity Degree of infilling of estuary based type of estuary based on Roy 1984 classification: 1 = immature - largely open water; 2 = semi-mature - 50% infilled; 3 = mature - largely infilled with sediment.
Estuary type Type of estuary based on Roy 1984 classification: 1 = drowned river valley; 2 = barrier estuary; 3 = saline coastal lagoon.
FeaturesList of features for this beach.
High TideIf true, then beach_state occurs at high tide If false, then beach_state occurs at low tide.
HoloceneThe extent of Holocene barrier deposits in hectares (usually dunes).
Inlet mouth Stability of inlet: 1 = always open; 2 = opens and closes; 3 = usually closed.
(Inlet) TrainedDoes the inlet have any entrance structures, such as training walls? (yes/no).
Inner BarIf true beach state applies to inner bar If false beach state applies to outer bar.
KeyUnique key for user identification - not for display purpose.
LengthMeasurement of the Beach Length (km).
LocationLocation of feature on or relative to the beach.
Mean (diameter)Mean diameter of the beach sediment (mm).
Mean BarsThe mean number of sandbars which form along the beach.
Mean fall velocityMean velocity of the beach sediment as it falls through water (m/sec).
Mean sea levelThe mean sea level will normally be midway between the high and low elevations.
Mode 1Mode or most frequently occurring sediment size (mm).
Mode 2 Second most frequently occurring sediment size (mm).
Neap tide Height of neap tide in metres.
Neap tide rangeThe neap range is the difference between the neap high and neap low.
OrientationThe orientation of the barrier in degrees. ie: the direction the barrier faces.
PleistoceneThe extent of Pleistocene barrier deposits in hectares (usually dunes).
Rip numberNumber of rip channels usually present along the beach.
Rip spacingAverage spacing of rip channels (in metres) usually present along the beach.
Sand flatsIntertidal sand flats located between base of beach and low tide.
Sand flat compositionSand flat - composed of sand; mud flat composed of mud.
SkewnessMeasures the deviation or asymmetry of the distribution. Positive skewness represents a fine tail to the distribution, negative a coarse tail, ranges from +1 to -1.
SortingA measure of dispersion or scatter, and is an expression of the standard deviation of the size distribution; ranges from very well sorted (<0.35, narrow distribution) to extremely poorly sorted (>4, wide distribution).
Spring tideHeight of spring tide in metres.
Spring tide rangeThe spring tide range is the amplitude between the highest & lowest. ie difference between the mean spring high water and mean spring low water.
StateAustralian state where beach is located.
Std VarStandard deviation of beach state.
Tide stationNearest standard tide station to a beach.
Type AttidID of feature type attribute.
Wave HeightThe mean breaker wave height at the beach (m).
Wave PeriodThe mean wave period at the beach (sec).
Wetland area Area in hectares of the lagoon or wetland (freshwater swamp or saltwater marsh) behind the beach.

Author

Andrew Short - University of Sydney

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