|
Term
|
Scope
Note
|
|
Clay
|
Sediment particle size < 3.9
µm
|
|
Silt
|
Sediment particle size 3.9–62.5
µm
|
|
Fine sand
|
Sediment particle size 62.5–250
µm
|
|
Coa
rs
e sand
|
Sediment particle size 0.25–2
mm
|
|
Gravel
|
Sediment particle size 2–64 mm
|
|
Cobble
|
Sediment particle size 64–256
mm
|
|
Boulder
|
Sediment particle size > 256
mm
|
|
Rock
|
Bedrock
|
|
Coral
|
Coral reef
|
|
Concretion
|
Concretion of iron oxide, sediments and cultural material
|
|
Shell
|
Shell and broken shell
|
|
Sea grass
|
Sea grass (Posidonia), usually on sand
|
|
Other
|
Another seabed type not listed above
|
