The Seamap Australia Substratum Component describes to the surface of any non-living material upon or within which biota can attach and grow. This typically consists of natural rock or mineral sediment, but also organic debris, man-made surfaces, and non-living biota (e.g. shells). In some cases, e.g. soft sediments or veneers, habitats may extend below the surface. In these situations Seamap Australia considers the uppermost 15 centimetres of the substratum
The Substratum Component can be paired with the Substratum Origin to give 8 total levels describing the non-living component of the seabed habitat. The Substratum Component describes the hardness and grainsize of the substratum, while the Substratum Origin describes the geologic of the substratum.
Level 4 subgroups
Level 4 subgroups further break down the Level 3 substratum classification into mineral grainsize. Descriptions and images of Level 4 classifications are embedded within Level 3 items in the Substratum Component Visual Classification Guide.
Unknown, or Not Assessed
An Unknown, or Not Assessed classification can be applied at any level within the hierarchy.
Other Seamap Australia Classifications​
Substratum Component Visual Classification Guide
Boulder
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Consolidated Hard Substrata
Clay
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Fine Sediments
Coarse Sediments
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Soft Substrata
Cobble
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Unconsolidated Hard Substrata
Consolidated Hard Substrata
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Hard Substrata
Fine Sediments
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Soft Substrata
Granule
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Coarse Sediments
Hard Substrata
Primary domain: Substratum Component
Classification level: Level 1
Parent classification:
Megaclast
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Consolidated Hard Substrata
Mixed Coarse Sediments
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Coarse Sediments
Mixed Consolidated Substrata
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Consolidated Hard Substrata
Mixed Fine Sediments
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Fine Sediments
Mixed Hard Substrata
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Hard Substrata
Mixed Hard/Soft Substrata
Primary domain: Substratum Component
Classification level: Level 1
Parent classification:
Mixed Soft Substrata
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Soft Substrata
Pavement
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Consolidated Hard Substrata
Pebble
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Coarse Sediments
Sand
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Coarse Sediments
Silt
Primary domain: Substratum Component
Classification level: Level 3
Parent classification: Fine Sediments
Soft Substrata
Primary domain: Substratum Component
Classification level: Level 1
Parent classification:
Unconsolidated Hard Substrata
Primary domain: Substratum Component
Classification level: Level 2
Parent classification: Hard Substrata
