BGS news

New seabed sediment maps reveal what lies beneath the waves

Marine ecosystem science and offshore infrastructure will be boosted by a new dataset showing sediment composition across the UK continental shelf.

03/09/2025 By BGS Press

Understanding the distribution of seabed sediments is important for a wide range of applications. © Kammeran Gonzalez-Keola, Pexels.

Characterising the distribution of seabed sediments (SBS) is critical for a wide range of applications, including:

habitat mapping
marine ecosystem science
mineral and aggregates assessments
offshore infrastructure siting and monitoring
defence
shipping
coastal management

BGS has developed the new national-scale BGS Predictive Seabed Sediments (UK) dataset aimed at supporting these applications. The dataset comprises four digital maps that portray SBS composition, including a classified map of sediment types, as well as the predicted proportions of gravel, sand and mud across the UK continental shelf.

These detailed maps are based on about 40 000 sample measurements, as well as numerous physical covariates that relate to the spatial distribution of SBS. They were generated with the assistance of machine learning.

Classified seabed sediment map of the UK continental shelf. BGS © UKRI.

Predicted proportion of sand in the UK continental shelf. BGS © UKRI.

Understanding the nature of the seabed is fundamental for many offshore activities, from understanding benthic habitats and carbon stores to effectively designing and installing offshore infrastructure, including wind turbines and submarine cables.

Seabed sediments lie at the interface between the water column above and the variable geological substrate below. To an extent, they can be considered similar to the soil layer on land, but offshore sediments are exposed to dynamic marine conditions and are therefore potentially transitory and mobile over variable timescales, for example, during tidal, seasonal and storm cycles.

We hope that the release of the new BGS Predictive Seabed Sediments (UK) dataset will provide a useful free resource for many users, including researchers, developers and marine managers.

Dayton Dove, marine geoscientist at BGS.

The BGS Predictive Seabed Sediments (UK) dataset is now freely available to download under the Open Government Licence (OGL) and can be used in combination with other thematic BGS 250K datasets that are also now available via OGL, such as bedrock geology. It can also be used with our more recently produced, high-resolution seabed geology mapping.

The Joint Nature Conservation Committee provided initial co-funding and supported this project.