Key information
Scale:
1:10 000 – 1:50 000Coverage:
RegionalAvailability:
FreeFormat:
Free to view via online map viewerUses:
Regional-level useGet data
Free access
The maps are free to view online via the BGS Offshore GeoIndex
Offshore GeoIndexSupporting documents
User guides are available via the links in the map series in the table further down the page below.
BGS has initiated a new programme of mapping the seabed geology of the UK’s continental shelf, the first effort to consistently characterise the geology of the seabed in over 20 years. These new, fine-scale maps provide detailed and accurate characterisation of the seabed geology, integrating substrate geology, structural geology and seabed geomorphology.

Dark blue area shows the coverage of the BGS Seabed Geology 10K: offshore Yorkshire map. Background image from World Ocean Base dataset compiled by Esri, Garmin, GEBCO, NOAA NGDC, and other contributors. Basemap created using ArcGIS. Copyright © Esri. All rights reserved. www.esri.com
The digital maps are intended as resources to support a diverse range of offshore activities and applications, including scientific research, offshore development, conservation initiatives and marine spatial planning and management.
The new mapping is based primarily on high-resolution bathymetry data produced by the UK Civil Hydrography Programme (CHP). Analysis and interpretation are further informed by secondary data and information resources, including:
- acoustic backscatter
- physical samples (for example grabs, cores and boreholes)
- seismic data
- academic and publicly accessible industry data and literature
- previous BGS mapping (onshore and offshore)
The CHP is administered by the Maritime and Coastguard Agency (MCA), with technical oversight, data validation and onward charting undertaken by the UK Hydrographic Office (UKHO).

BGS Seabed Geology 10K: Anglesey map, showing geomorphology layers (lines and points), structural geology, substrate geology and hillshade. Contains OS data © Crown Copyright and database right 2020. The underlying hillshade image is derived from bathymetric data acquired by the MCA © Crown Copyright 2022, released under OGL.

Section of the BGS Seabed Geology 10K: Anglesey map, showing geomorphology layers (lines and points), structural geology and substrate geology. Contains OS data © Crown Copyright and database right 2020.

Section of the BGS Seabed Geology 10k: Anglesey map, showing geomorphology layers (lines and points) and hillshade. Contains OS data © Crown Copyright and database right 2020. The underlying hillshade image is derived from bathymetric data acquired by the MCA © Crown Copyright 2022, released under OGL.

Section of the BGS Seabed Geology 10k: Anglesey map, showing bathymetry data (depth and hillshade). Contains OS data © Crown Copyright and database right 2020. The underlying hillshade image is derived from bathymetric data acquired by the MCA © Crown Copyright 2022, released under OGL.

Section of the BGS Seabed Geology 10k: Anglesey map, showing geomorphology layers (lines and points), structural geology, substrate geology and hillshade. Contains OS data © Crown Copyright and database right 2020. The underlying hillshade image is derived from bathymetric data acquired by the MCA © Crown Copyright 2022, released under OGL.
Product summary
The new fine-scale BGS Seabed Geology mapping comprise three complimentary components (or layers):
- substrate geology: distribution of bedrock and superficial geological units interpreted to be dominant within the top 1 m below seabed
- structural geology: principal structural features such as faults and folds observed at rockhead
- seabed geomorphology: physical morphology and interpreted geomorphic character of the seabed
Further detail on the mapping process and dataset characteristics are described within individual dataset user guides.

Available fine-scale maps
The BGS Seabed Geology maps can be viewed under the BGS fine-scale maps drop-down menu within the Offshore Geoindex.
Map | User guide | Further information |
---|---|---|
Anglesey | Available in NORA | Press release |
Bristol Channel | N/A | Press release Geology blog |
Dorset* | N/A | Research page |
Offshore Yorkshire | Available in NORA | Press release |
* Bedrock and structural geology only. The Dorset map was produced under the auspices of the Marine Environmental Mapping Programme (MAREMAP), in collaboration between BGS and the University of Southampton.
Relative topics
Related news

New seabed geology maps for offshore Yorkshire
14/03/2023
Offshore Yorkshire is the latest map to be released in BGS’s series of fine-scale digital seabed maps.

BGS Seabed Geology
The seabed geology map dataset covers regions on the UK’s continental shelf and details the substrate geology, structural geology and seabed geomorphology.

New geological map of offshore Anglesey released
10/10/2022
BGS has released a new fine-scale digital map featuring the seabed geology of offshore Anglesey (Ynys Môn).

New seabed maps offer a window into the distant past
10/10/2022
BGS has begun publishing a new series of high-resolution offshore geological maps showing the distribution of bedrock and sediments that make up the seabed around our coasts.

BGS joins the UK Centre for Seabed Mapping to raise data and mapping standards
25/08/2022
BGS is the latest UK Government organisation to join the newly unveiled UK Centre for Seabed Mapping, helping to boost marine data and mapping standards.

BGS releases first in a series of new offshore maps of the UK seabed
06/04/2022
BGS has released the first high-resolution, offshore map in a new series featuring the seabed around the UK.
You may also be interested in:

Seabed sediments 250K
The 1:250 000-scale offshore geological maps for seabed sediments are available digitally.

Offshore bedrock 250K
The 1:250 000-scale offshore geological map for bedrock geology (BGS Geology: marine bedrock 250k) is available digitally.

Sea floor: marine geoscience
The marine geoscientists at BGS provide independent and expert geological advice, research and data acquisition to anyone working in the marine environment.