Geo-Seas is Europe-wide infrastructure for managing geological and geophysical marine and ocean data for hydrographic purposes on sites which are of interest to maritime navigation. The current description is limited to making bathymetric data available within the context of the project.

G maps represent the nature of the sea floor in the background of a maritime map used in navigation. Most such maps are published at a scale of nearly 1/50 000, and are as often as possible drawn up within the context of collaborations with university laboratories with knowledge of the area to be mapped.