The 51ÁÔÆæ (BGS) has released a new shallow subsurface geological synthesis of the southern North Sea in the first formal review of this region since the 1990s. A wealth of new subsurface data has been generated through the rapid expansion of offshore wind farm (OWF) development since the last assessment.

In total, the new synthesis draws on data from 22 OWFs and cable landfall sites from recent publications and open data available through The Crown Estate . Bringing these diverse datasets together presented a rare opportunity to enhance our geological understanding of the region, providing a detailed baseline resource to support more efficient and better-informed offshore development projects in the future.

Findings from the updated review have revealed much greater geological complexity within the region than indicated by the previous assessment, which was developed between the 1970s and 1990s on the back of data collected during oil and gas developments. Modern OWF investigations, supported by comprehensive borehole drilling, cone penetration tests and seismic datasets, show that many of the geological formations contain a variety of distinct sedimentary characteristics. This complexity has direct implications for foundation design and ground modelling, including the identification of geo-engineering constraints and geohazards, which is crucial information for a wide range of offshore infrastructure development.

The assessment examined evidence across pre-glacial, glacial, interglacial and post‑glacial periods from 200 million years ago to the present day. Understanding how different sedimentary units were deposited provides vital insight into geological formations that may present specific geo-engineering complications. This includes mixed soils, boulders, glacially compacted sediments or organic-rich layers. Organic units can be problematic for cable installation due to their fibrous nature, presenting considerable challenges to cable routing.

It is not a requirement for UK offshore infrastructure projects to collect samples for dating and biostratigraphy; however, where they are available, absolute dating (radiocarbon and optical stimulated luminescence data) information has also been included within the assessment. Neighbouring countries such as the Netherlands recognise the value of this data, as it can help to better predict age-based sedimentary characteristics and ultimately better inform geotechnical characterisation around a project design.

The report outlines several recommendations to enhance the resource further, including improving fine-scale mapping, ingesting geotechnical datasets for each geological subunit and strengthening international collaboration to harmonise North Sea stratigraphy. The findings presented in the main report can be aligned with results presented in the , which is a data catalogue highlighting the key geological features and associated engineering constraints for OWF development as part of the . Both resources provide complementary datasets and criteria essential for evaluating OWF site suitability.

This work provides:

• an opportunity to advance scientific understanding
• resources to strengthen national collaboration
• supporting baseline evidence for the energy transition, energy security and wider marine planning
  

The release of this report marks an important milestone in compiling geological observations from literature and offshore wind farm development over the past 30 years or so. It brings together a wealth of new offshore geological data that enhances our understanding of the shallow subsurface in the marine environment in the southern North Sea. We hope this dataset will provide strong baseline evidence to support national and international collaboration for efficient offshore development and act as a blueprint for other areas around the UK Continental Shelf.

Nikki Dakin, BGS Senior Marine Geoscientist

We would encourage similar consolidation of geological information across the wider North Sea, Celtic Sea, Irish Sea, The Solent and English Channel, making full use of the substantial dataset holdings within the Marine Data Exchange. There is also significant potential to extend this approach internationally, working with neighbouring countries.

Such data provides a robust evidence base for industry, regulators and researchers, marking an important step toward a fully modernised geological model and improving our understanding of offshore stratigraphy across the UK Continental Shelf.

The report and geological assessment are now available online: .

51ÁÔÆæ would like to acknowledge The Crown Estate as well as wind farm developers for contributing reports and data to The Crown Estate Marine Data Exchange.

The BGS BritPits dataset contains more than 264 000 records of onshore mineral workings located in Great Britain, Northern Ireland, the Isle of Man and the Channel Islands. The data includes active, inactive, dormant and ceased sites, as well as a range of mineral operations including mines, quarries and onshore oil and gas fields, together with wharfs and rail depots handling mineral products and industrial processes. Each record describes an onshore mineral working in terms of its name, operational status, geographical location, Mineral Planning Authority (MPA), operator, geology, worked mineral commodity and a range of relevant metadata.

Three levels of BGS BritPits data are available. The open-source index is based on the full BritPits dataset but contains index level information only, including the name, status and location of the working. This can be accessed as a Web Map Service (WMS) layer or via the . The other two levels are available as licensed datasets.

• The open-source index package is available under an Open Government Licence
• The full dataset includes all the entries of the BGS BritPits database, including historic sites; this data is also available for specific Mineral Planning Areas
• A subset of the full dataset that contains only the active, inactive and dormant mines and quarries (over 5200 entries)

These datasets are updated every year. The latest version, released in February 2026, contains 264 549 records, an increase from 262 814 records in the previous version.

This data will be of use to organisations in the public and private sector who have an interest in the location of mineral extraction sites and their possible after-use. For example, the data has been supplied to:

• national and local governments for use in planning and statistical studies
• non-governmental organisations for environmental and conservation planning
• commercial organisations for analysis of resource potential and legacy operations

As the UK works toward its net zero ambitions, attention is increasingly turning offshore, where geological formations under the sea floor may hold the key to long-term carbon dioxide (COâ‚‚) storage. 

Carbon capture and storage (CCS) encompasses a range of technologies designed to significantly reduce emissions from large industrial sources such as steelworks, cement plants and thermal power stations. COâ‚‚ is captured at source, transported and then injected into suitable rock formations deep beneath the surface, typically at depths of over 800 m. Geologists at BGS are working to better understand the subsurface geology of the Central North Sea and its suitability for storing COâ‚‚ captured from major industrial sources. This work could release one of the UK largest, yet least-developed, carbon storage resources and underpin the in CCS projects.

Despite accounting for approximately 60 per cent of the UK total estimated COâ‚‚ storage capacity, the Central North Sea remains under-represented and highlights a major opportunity for the Government clean energy growth agenda. 

A nation rich in storage potential 

Deploying CCS at scale is a key pillar of the UK Government . Current ambitions are to store at least 50 million tonnes of COâ‚‚ per year by 2030, rising to as much as 170 million tonnes annually by 2050. 

The UK is exceptionally well positioned for offshore COâ‚‚ storage. Estimates suggest that total theoretical storage capacity exceeds 70 billion tonnes. The North Sea Transition Authority (NSTA), which regulates offshore COâ‚‚ storage, launched its first competitive licensing round in 2022 and followed this with a second round announced in December 2025. 

These licences allow operators to explore and appraise potential storage sites as a precursor to applying for permits that enable COâ‚‚ injection. Due to favourable geology and proximity to onshore emission hubs, most licences to date have been located in the Southern North Sea, with additional clusters in Liverpool Bay, Morecambe Bay and the Northern North Sea. However, the region with most storage potential lies elsewhere.

The drive to map this untapped potential

The enormous, currently untapped potential beneath the Central North Sea lies in extensive sandstone formations in the region. Multiple sequences of stacked Palaeogene sandstone units represent a vast potential COâ‚‚ storage resource, with more than 10 billion tonnes of theoretical capacity (approximately one quarter of the basin total regional storage capacity). These sandstones were deposited between 40 and 65 million years ago in deep-water marine fan systems. The complex stacked and interdigitated nature of these sandstone bodies raises important geological questions that must be resolved before large-scale storage can proceed.

Key considerations include: 

• the degree of connectivity between sandstone units, which has a bearing on pressure during CO₂ injection
• balance between pressure dissipation and pressure interference between neighbouring storage sites, which affects storage capacity
• the effectiveness of the vital sealing layers above and between the sandstone formations, which might be prone to disruption by various geological phenomena
• legacy oil and gas wells, which could act as pathways for CO₂ to escape if not properly assessed

With relatively few licences currently issued in the Central North Sea, robust pre-competitive geological understanding is essential to realise the region storage potential. BGS geologists have therefore begun a comprehensive programme to better understand the Palaeogene storage system. This work will also help to address regulatory and operational challenges, particularly those related to pressure effects and interactions between disparate storage projects.

John Williams, senior geoscientist at BGS.

Decades of oil and gas exploration have generated a wealth of subsurface data, including drill core that is curated in BGS National Geological Repository. Drilling core is expensive, costing as much as £20 to 30 million for a single offshore borehole, so the ability to access pre-drilled material is invaluable, both in terms of avoided drilling costs and time saved. Alongside this archived material, BGS has also developed an integrated subsurface database and interpretations comprising existing 3D seismic and well data, and a stratigraphical framework to ensure accurate regional interpretation.

From the late 1990s to the early 2000s, BGS undertook pioneering work to evaluate the potential to reduce greenhouse gas emissions by storing COâ‚‚ in rocks offshore UK, to help mitigate climate change and develop clean energy. This early work focused on the geological storage opportunities in the Southern North Sea and East Irish Sea regions.

Potential storage sites in these regions, first identified by BGS, are among the first to be licensed and permitted by the NSTA for COâ‚‚ storage. For the UK to reach its ambition of storing 170 million tonnes of COâ‚‚ a year by 2050, it will need to look beyond the current well-appraised geographical areas.

The stacked sandstones of the Central North Sea are relatively under-studied, with huge COâ‚‚ storage potential. Our ambition is to assess and characterise the potential geological storage system in this region to enable future COâ‚‚ storage in the UK, fast-tracking the nation CCS industry.

Michelle Bentham, chief scientist for decarbonisation and resource management at BGS.

51ÁÔÆæ is seeking to establish partnerships to help unlock this nationally significant COâ‚‚ storage resource, which could play a crucial role in the UK transition to a low-carbon future. Interested parties should contact John Williams via enquiries@bgs.ac.uk

51ÁÔÆæ has developed a new, national-scale, offshore dataset that shows the distribution of previously interpreted Quaternary rock layers in the shallow subsurface of the UK continental shelf.

The BGS Offshore Quaternary 250K datasetcomprises a compilation of legacy BGS 1:250000 Quaternary geology map sheets, which were first published in the late 1980s to early 1990s. Large areas of the UK offshore are covered at a scale of 1:250000 and this is the first time these map sheets have been digitised and merged together.

The dataset is made up of vector polygons, each representing an area where a particular formation has been mapped. The legacy map sheet interpretations have not been modified during the digitisation; they are presented in their original form and have been ‘mosaiced’ together as a single digital product.

The dataset will help users, particularly those in the offshore renewables sector, to understand the stratigraphy that was mapped historically in a particular area and can be used for reference when completing site investigations.

The principal drive behind this release is to make original 1:250000 map data available in a digital format. Although work to refine Quaternary stratigraphical frameworks is ongoing, the map compilation is not informed by new data or analyses.

The Offshore Quaternary 250K dataset is the first time that these legacy offshore map sheets will be digitised, making it easier for users to access the data than ever before.

Andrew Dyson, marine geoscientist at BGS.

Geologists at BGS have completed a major update to the geological map of the Yorkshire Wolds, where the underlying rocks and sediments play a vital role as natural reservoirs for the region underground water resources.

The distinctive white chalk rock of the , which forms the magnificent coastal cliffs, is also present beneath the wolds. The chalk is an ‘aquifer’ and is important as the primary drinking-water source for the area. The new geological mapping will provide detailed and accurate information to inform decision making around the use of groundwater resources.

The geology of some of the area was last mapped in the 1800s, before modern understanding of the impact of tectonics (movement of the ’plates’ that make up the Earth crust) on the chalk and before information about differences in the properties of the chalk layers was recorded. At that time, there was no satellite data and underground data was limited, so maps were mostly based on ground observations, with much of it done from horseback! The new mapping provides updated geological data and information for the region and plays a central role in the current BGS national geological mapping programme.

The five-year project involved different remote techniques, including interpretation of 2D seismics (information from small, controlled vibrations that create waves through the rock, which can then be used to map the subsurface), digital elevation models, aerial imagery and borehole records along with field surveys and palaeontological (fossil) analysis. Collectively, these methods and data have significantly improved geological understanding of the chalk aquifer.

The aquifer currently faces a number of pressures, including:

• increased water demand from a growing population as well as industrial uses
• risk of nitrate contamination from agricultural land practices
• risk of salt water from the Humber estuary reaching the aquifer and mixing with drinking water
• improvements to habitats, for example chalk streams

We need to better understand and model how water flows in the Chalk aquifer and the interaction between springs, rivers and abstraction. The new mapping delivers enhanced knowledge that will help to improve regional understanding of both the aquifer and the groundwater resources, as well as localised geological issues that may assist in reducing risks to specific water supply assets, such as water abstraction sites.

Over the past hundred years since the geology of the Yorkshire Wolds was last mapped, our ability to better understand what lies beneath our feet has vastly improved thanks to technological advances and a modern understanding of geology. The updated geological maps will help companies, farmers, local planners and regulators make more informed decisions around the management and protection of the chalk aquifer in the Yorkshire Wolds.

The data also provides a solid geological framework to underpin future work to help mitigate present and future issues faced in the Yorkshire Wolds, including drought, coastal erosion, water quality and saline intrusion into the aquifer.

Laura Burrel Garcia, survey geologist at BGS.

The project was a collaboration between the Environment Agency (EA), Yorkshire Water Services Limited (YWS) and BGS. Recently, EA, YWS and WSP attended BGS headquarters in Keyworth, Nottinghamshire, to discuss the conclusion of the project and its outcomes.

The team at the BGS has not just remapped the Yorkshire Wolds; they have also shared their expertise and enthusiasm with all. The outputs of this project will benefit the people of Yorkshire for centuries to come and will greatly assist the Environment Agency in our work to create better places for people and wildlife, while supporting sustainable development.

Ruth Buckley, Environment Agency.

This project has been a wonderful example of collaboration and shared learning. The BGS team members were generous with their time, sharing their expert knowledge of field mapping and interpreting the modern information. It was a pleasure to work with them. The end result is a huge improvement in the collective understanding of the geology, which will feed into improvements in understanding of groundwater flow and a new groundwater model based on the new geology maps. This gives us the ability to better manage East Yorkshire water resources and protect the environment now and into the future. A big thank you to all involved.

Mark Morton, Yorkshire Water Services Limited.

The data produced from this work will form part of the national geological map, which will be freely accessible via the.

Groundwater flooding is the emergence of groundwater at the surface, which can occur in a variety of geological settings, including areas with historical mining. In England and Wales, it estimated that groundwater flooding accounts for an estimated £530 million in damages per year.

Project Groundwater Northumbria aims to increase awareness and understanding of groundwater flooding and help prepare for and mitigate flood events through innovative approaches and technologies. The project, in which BGS is a partner, is led by Gateshead Council and is part of the Environment Agency Flood and Coastal Resilience Innovation Programme.

Following a major groundwater flood event in Gateshead in 2016, along with several smaller incidents, BGS has constructed a subsurface map and produced a free, 3D geological model of the bedrock in Gateshead. These help better understand the sequences and geometries of the shallower soil layers (superficial deposits) at tens of metres of depth, alongside structures and boundaries in the bedrock to several hundred metres of depth.

The north-east of England was a major centre for coal mining. In areas with historical mining activities like Gateshead, the effect of mine workings on groundwater movement can be significant. The map and model will give a better understanding of how the natural subsurface conditions, combined with the legacy of human activity in the subsurface such as abandoned coal mines, affects the direction of groundwater flow.

The insight provided from the anticipated groundwater flow paths will help identify where groundwater flooding is likely to occur. This will allow Gateshead Council (and other organisations, such as the Environment Agency and Northumbrian Water) to better deploy resources more effectively and monitor the speed and spread of flooding in real time, to help manage and alleviate groundwater flooding in the area.

The 3D geological model of Gateshead, released as part of Project Groundwater Northumbria, will help us to understand the impact of groundwater movement in this area and improve Gateshead Council response to future floods.

The model is an innovative step forward in how we capture data. Traditional geological maps don’t allow to us to show the interaction of mine water and groundwater, but we can showcase them with this model. It has really helped us to improve our 3D understanding of coal fields and how water flows through them. In turn, this is part of a wider programme of 3D urban geology across the country.

Project Groundwater Northumbria showcases how multiple organisations can work together on one project with the same aim and highlights the geological and technologies advances that can be achieved.

Ricky Terrington, BGS 3D Geospatial Lead and project leader.

The 3D geology model for Gateshead can now be accessed for free on BGS.

The reports produced as part of this project are available to read:

51ÁÔÆæ Geology, BGS digital geological maps covering Great Britain, is based on a suite of published paper maps enhanced with latest digital mapping. It is periodically updated with information from field surveys as well as including previously unpublished maps or additional interpretation.

The latest version of BGS Geology 50K now covers the majority of Great Britain plus the Isle of Man, an estimated 236000km². This includes coverage for approximately 99per cent of the bedrock and approximately 95per cent of the superficial deposits across the country.

These geological maps provide crucial information like rock types and faults, forming a valuable resource for a wide range of uses, such as infrastructure planning and development, including ground source heat pumps, and environmental assessment.

The 50K-scale map offers a balance between detail and coverage, making it highly useful for a wide range of applications, from regional assessment to local-scale intelligence.

The latest update incorporates all edits to the dataset since the previous version release in 2017. This includes new and revised tiles of geology data, updates to the coastline and various corrections to geological features across the country. Also included is additional attribution on linear features depicting fault trace handedness and hanging-wall orientation on fault features.

Henry Holbrook, data sharing lead at BGS.

In addition to the 50K maps, BGS has also updated its 10K and 25K maps. BGS Geology 10K and 25K is the most detailed geological dataset we have produced Around half of the country is now covered with this update, including many urban centres and transport routes in Great Britain.

This latest release of BGS Geology 10K and 25K includes new maps and is based on our highest-resolution survey mapping. It will continue to be of great help to the public sector, the construction industry and academics.

Henry Holbrook

51ÁÔÆæ data for both BGS Geology 50K and BGS Geology 10K and 25K is available under licence. You can also view the BGS Geology 50K map data in the GeoIndex viewer. Further information about 51ÁÔÆæ Geology 50K and 51ÁÔÆæ Geology 10K maps is available on the BGS website.

Renewable energy infrastructure, whether on- or offshore, requires in-depth understanding and accurate characterisation of the underlying geology.  Developers increasingly need detailed geospatial observations of the seabed and shallow subsurface, which are critical to the siting and design of offshore infrastructure such as submarine cables and offshore wind turbines. This is certainly true in the Bristol Channel, which is home to the second largest tidal range in the world. This high-energy environment has attracted much interest around the use of the seabed for tidal power and the potential to produce electricity from wave energy.

To support policy- and decision makers in this region, BGS has released an enhanced seabed geology map of the Bristol Channel, almost four times the size of the original, which extends from Carmarthen Bay to Newport and further south to the coast of Somerset.

Beyond offshore infrastructure, these maps also directly contribute to understanding of marine ecosystems, coastal management and defence activities. The data provides crucial information to those ensuring the port facilities along this coastline meet the requirements for these development opportunities.

As the UK transition to renewable energy gathers pace, these maps will become increasingly valuable to industry and stakeholders with an interest in developing clean energy, from offshore wind to tidal streaming, and in carbon capture and storage.

The successful implementation of offshore renewable energy projects and technologies and the development of ports in South Wales require a detailed understanding of the seabed. This new, expanded, fine-scale seabed map of the Bristol Channel will be an invaluable resource for developers, providing access to high-quality, detailed observations of the seabed geology that is vital to these kinds of developments.

Beyond its critical role in supporting the renewables sector, the map will also be useful to other data users, such as those involved with supporting marine ecosystems, coastal management and defence activities. It will also provide evidence for policy- and decision makers in the region.

Rhian Kendall, BGS Chief Geologist for Wales.

The map, featuring combined bedrock, sediment, bedrock structure and seabed geomorphology data, is available from BGS under the fine-scale maps section of theand is designed to be viewed at 1:10000 scale, or online as downloadable shapefiles. For information on licensing the downloadable GIS data (ESRI format), please contact digitaldata@bgs.ac.uk.