Acoustic mapping: side-scan sonar and multibeam explained

Sound reaches where light cannot. How acoustic surveys draw the seabed, and what they cannot tell you.

By Sample content (demo) October 20, 2026

Sample Sample content — created to show how the Knowledge Platform works. It is not an official Life Mapper publication.

© Markus Bachofner · CC BY-SA 4.0 · Wikimedia Commons

Seeing with sound

Below a few tens of metres, satellite images stop seeing the bottom. Acoustic instruments take over: a multibeam echosounder measures depth across a wide swath, while a side-scan sonar records how strongly the seabed reflects sound, which hints at sand, rock or vegetation.

Planning a survey

Choose line spacing so that swaths overlap.
Record sound-velocity profiles: water layers bend the signal.
Plan ground-truth stations for every acoustic class before leaving port.

Data to start from

Database EMODnet Bathymetry: European seabed depth model Harmonised depth data for European seas, the base layer of most habitat maps. Open in the catalogue

Sources

Go deeper

The papers, case studies, tools and platforms this page builds on.

Database EMODnet Bathymetry: European seabed depth model Depth is the first layer of any acoustic interpretation. Open in the catalogue

Catalogue

Chapter

Mapping and data

Level

Intermediate · 7 min read

On the map

See North Sea in the geoportal ↗

Geographic area

Thematic area

Habitat mapping

Habitat group

All habitats

Methodology

Keywords

Part of these guided paths

Map a meadow from scratch

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