Bathymetry

Bathymetry is the measurement and mapping of underwater depths and submerged terrain, especially the seafloor. Its maps reveal underwater relief using depth measurements and elevation contours.

Multibeam echosounder: A sonar system that measures water depth across a wide swath beneath a vessel. It builds detailed seafloor maps from many acoustic beams measured at once.
Nautical chart: A map designed for marine navigation, showing depths, hazards, coastlines, and aids to navigation. Charted soundings and contours help vessels avoid grounding.
Hydrography: The science and practice of measuring and describing physical features of oceans, seas, and navigable waters. Bathymetry is one part of hydrography, alongside shoreline and water-level observations.
General Bathymetric Chart of the Oceans: An international project and map series that compiles and shares global ocean-floor bathymetry. GEBCO turns scattered measurements and modeled depths into a shared global dataset.
Side-scan sonar: A sonar system that images seafloor texture by recording sound reflected towed sensors. Its acoustic imagery complements depth measurements by showing seabed features and objects.
Hydrographic survey: The systematic measurement of water depths and related features for navigation and marine use. Bathymetric mapping is a central output of hydrographic surveys.
Sounding: A measurement of water depth at a particular location, usually referenced to a vertical datum. Individual soundings are the observations from which many depth maps are assembled.
Seabed 2030: A global initiative to map the world's ocean floor by 2030 and make the data publicly available. The initiative focuses attention on gaps in modern bathymetric coverage.
Satellite-derived bathymetry: The estimation of shallow-water depths from satellite measurements of reflected light. It extends depth mapping across clear, shallow areas without ship-based surveys.
Seamount: An underwater mountain rising from the seafloor without reaching the sea surface. Bathymetry reveals seamounts that can influence currents and host distinct ecosystems.

Linked from 34 pages