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Thematic map - Bottom sediments

Map information

The data set shows the grain size composition in the upper part of the seabed sediments (upper 0-50 cm of the seabed). Grain size data are based on analyzes of seabed samples, analyzes and interpretation of digital reflectivity data, as well as interpretation of analogue and digital seismic data. Detailed water depth data and video of the seabed have been included to support the interpretation. Theme codes and properties mainly follow the SOSI standard, version 4.0. In the property table of the data set, information is given about the different grain size classes and which term is used based on the content of different fractions in sediments. By grouping grain size classes in a geologically sound way, the dataset can be visualized as other thematic maps, such as Sedimentation areas (areas where fine-grained sediments are deposited), and Excavability (sediments grouped and presented according to how easy it is to dig in the bottom). Based on information about grain size distribution, other topics can be further developed, such as sedimentation environment, bottom current data, anchoring conditions, etc.

The map below shows coverage for the data. Zoom in to see if there is data for your area.

The map is taken from

Downloadable map for Simrad, Lowrance and B&G

The map is produced according to drawing rules from NGU and documentation can be downloaded from here.



Below is a screenshot of the map shown on a Simrad NSS9 Evo2 together with the C-Map EN-Y300.


Screenshot of chart plotter.

The main category for this map is called "Bottom sediments" and you can turn off the main category itself (and thus all subcategories) or the various subcategories independently of each other. Once you have set up the view the way you want it, the chartplotter will remember this setup the next time you turn on the chartplotter.


Downloadable map for Simrad, Lowrance and B&G

The theme map is available in the following versions (click on the download link):

NB! The maps available on this site are for personal use only at your own risk. They shall not be resold or otherwise distributed outside this site.

Back to the main page of the map portal

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