Acoustic backscatter. Bottom reflectivity mapped with multibeam echosounder, 50 m grid. The strength of the acoustic signal reflected back from the seabed.

Sediment thickness above bedrock on the Norwegian continental shelf.

Index layer showing the areas where mapping and/or modelling of shell sand is carried out.

The map layer shows areas with detailed sediment maps (grain size).

Distribution of shell sand localities based on modelling. Modelling is based on data collected by NGU, and carried out by NIVA, in the frame of nation program for mapping of biological diversity.

Terminal moraines (ice marginal deposits) in Norwegian fjords and coastal areas are mapped because of their importance to organisms living on or above the seabed. Terminal moraines are interpreted based on available detailed bathymetry data.

The map layer shows the spread of bioclastic sediments consisting of particles formed from the decomposition of mainly calcareous organisms, and may contain all grain sizes from clay to block. The map layer contains no information about the proportion of living and dead organisms.

The map layer shows areas with detailed sediment maps (genesis).

The map layer presents several thousand points with bottom information (grain size and sediment type) in fjords and coastal areas.

Map layer shows surface sediments (superficial deposits) on the seabed in mapped areas along the Norwegian coast. Superficial deposit as a property describes the mode of formation (genesis). The maps are digitized with a view to presentation at a scale of ca. 1:100 000 - 1:250 000 (regional mapping).