This product includes a map of the peaks of around 3,000 submarine dunes entered using bathymetric surveys by Shom. Each dune is marked out by a line showing its peak summit. Dune locations are precise to between 1 m (MBES data from the 2000-2010 period) and a dozen metres (data acquired prior to 2000 using a side sonar). The precision of the carrier location, the acquisition system and the MBES resolution (the distance between the systems acquired) also affect map precision. Submarine dunes can move at the rate of a few metres per year, but can also exceed 30 m/year. The precision of dune positions will therefore decrease with the age of the measurement.

The product "Distribution of the submarine dunes of the French continental shelf" contains digital vector data provided as 2D linear objects representing the crest of submarine dunes digitized from bathymetric surveys conducted by the Shom. When several surveys have been carried out on the same area or dune, the product contains the information from all the surveys. However, the data displayed on data.shom.fr is limited to the information from the most recent survey.

The product "Distribution of the submarine dunes of the French continental shelf" contains digital vector data provided as 2D linear objects representing the crest of submarine dunes digitized from bathymetric surveys conducted by the Shom. When several surveys have been carried out on the same area or dune, the product contains the information from all the surveys. However, the data displayed on data.shom.fr is limited to the information from the most recent survey.