The Mineral Exploration and Investment Grants Act 1972 (MEIGA) provided a stimulus for mineral exploration in the UK. Under the Act, the Government’s Department of Trade and Industry gave grants for mineral exploration for non-ferrous metals, fluorspar, barium minerals and potash. Compiled largely during the 1970s and 1980s, reports detailing the exploration undertaken contain a rich variety of information, including geological mapping, soil and stream sediment geochemistry, geophysical surveys, drillcore logs and assay data.

Previously, these ‘MEIGA’ reports were only available to view in hard copy through BGS’s National Geoscience Data Centre (NGDC). In 2023, a digitisation programme, carried out in collaboration with the UK Critical Minerals Intelligence Centre (CMIC), released an initial batch of over 200 . A further release of digitised reports this year (2026) has meant that an additional 660 reports have been added to the accessible collection, ensuring that data collected over forty years ago is openly available and newly relevant for identifying critical and precious metal resource potential within the UK.

The significance of this release is already being demonstrated in the Ardlochan area of south-west Scotland. At the end of 2025, completed a in the area, which discovered a large, vertical tube of broken rock (a ‘breccia pipe’ system) that was at least 140 m wide and rich in gold. The company then drew on MEIGA materials, originally generated by exploration companies Noranda Mining Limited and Phelps Dodge in the 1970s and 1980s, to complement its own surveys and recent drilling in order to target other sites of interest.

The MEIGA dataset for Ardlochan is already playing a key role in refining a new generation of exploration targets, especially those associated with gold-rich porphyry–breccia systems. A major advantage of the datasets is that they capture Ardlochan at a time when the area was largely unforested. This allowed for far more detailed bedrock mapping than is possible today and provides a clearer geological framework from which to work.

Just as importantly, the reports offer insight into the exploration concepts and decision making used by major operators in the 1970s and 1980s. These companies invested heavily in systematic regional work, identifying features and prospects that were subsequently forgotten as corporate priorities shifted. Integrating these historic insights with modern techniques is enabling us to rebuild the geological story of Ardlochan and accelerate target development with a level of confidence that would not otherwise be possible.

Calum Lyell, Western Gold Exploration.

Exploration can be very expensive and uncertain, often requiring companies to repeat baseline surveys to establish context. By providing open access to MEIGA reports, BGS (through CMIC and the NGDC) is helping to reduce duplicate efforts, enabling more targeted investment. For smaller firms, this pre-competitive data supports innovation and lowers barriers to entry.

The digitisation of BGS archive documents is a major effort in valorising legacy datasets that can have a major impact at minimal cost for the exploration sector. We are continuously working towards refining accessibility to these documents, notably applying various machine learning methods to automate the extraction of data contained in these pages to make them publicly available, as well as developing large language models for personalised, one-to-one interaction with the archived volumes.

Pierre Josso, deputy director, CMIC.

For the National Geoscience Data Centre, the renewed impact of the MEIGA archive demonstrates exactly why long‑term stewardship of geoscience data matters. Historic materials only realise their full value when they are preserved, digitised and made accessible. Funding the systematic scanning of these legacy collections is essential not only to safeguard the record, but also to ensure that insights captured decades ago can actively inform modern exploration, reduce duplication of effort and unlock new scientific and economic opportunities. The success at Ardlochan shows that well‑curated archives don’t just tell the story of past work; they directly enable the discoveries of today.

Alison Steven, data operations and governance lead, NGDC at BGS.

More than 700 additional geological samples from the vicinity of the ceased Foss Mine near Aberfeldy, Perthshire, are now available for study at the National Geological Repository (NGR), located at BGS’s headquarters near Nottingham. The sample set, comprising outcrop and drillcore, was originally collected in the 1980s by Dr Norman Moles, who was undertaking research on the Foss deposit for his PhD at the University of Edinburgh. The samples complement existing NGR holdings of runs of drillcore from exploration drilling of the Foss and Ben Eagach–Duntanlich baryte deposits in the 1980s.

The fully catalogued collection of 717 specimens will be of interest to scientists for a range of further studies. Such studies could include investigations of critical metal potential, following a 2023 report by BGS that highlighted the central Perthshire region as one of the UK’s prospective areas for critical raw materials. The mine was the main source of baryte, or barium sulfate (BaSO₄), in the UK from the early 1980s until its closure in 2021. Baryte is primarily used in the oil and gas industry to help stabilise boreholes during drilling and was extensively used in the North Sea. Associated with the bedded baryte deposits are rocks rich in barium feldspars and micas, as well as sulfide and carbonate minerals.

Alongside the Foss material, the NGR houses the UK’s foremost collection of geological samples. This includes over 16 million geological specimens, including 600 km of drillcore and 200 000 thin sections. Boreholes take time to drill and can be very costly, so a shared repository of ground information, such as the collection held within the NGR, provides scientists access to pre-drilled samples for further research and analysis, saving significant project costs and accelerating timelines. The core from the site of the former Foss Mine is another example of how our relationship with the subsurface is ever evolving, sometimes in ways that can be hard to predict.

Cores from the Foss Mine, once used for the oil and gas industry, could now be a valuable resource for future research, potentially holding the secrets of critical mineral prospectivity that are essential for the clean energy transition.

Mark Fellgett, NGR facility lead at BGS.

Beyond mineral prospectivity, the nature of the rock formations in this region holds wider scientific value. Due to its age dating back to the Ediacaran Period of the Precambrian, approximately 539 to 635 million years ago, the material can also be used to study a marine environment that was very different to the present.

The core could be used for stratigraphical studies of the Ediacaran Period following the ‘snowball Earth’ of the Marinoan glaciation [at least 654.5 million years ago]. Analytical techniques developed since my PhD research, such as transitional metal stable-isotope analysis and laser ablation inductively coupled plasma mass spectrometry, could be applied to gain further knowledge of the hydrothermal processes and local and global environments at this pivotal time in the Earth’s history.

Dr Norman Moles.

BGS is progressively scanning and digitising the NGR collections and some of them are now available online. The GeoIndex is an easy-to-use, searchable map interface that enables users to find all data and information held by the BGS for any part of the UK, both onshoreÌý²¹²Ô»åÌýoffshore.

To arrange a visit to access this material, go to the accessing the NGR material collections page. You can also .  

For general enquiries, please contact BGS Enquiries (enquiries@bgs.ac.uk) or call 0115 936 3100.

Sand is the most extracted solid material on Earth (currently 50 billion tonnes annually). Rapid urbanisation, driven by large-scale migration into cities, has fuelled a growing need for sand as a building material, with demand expected to rise by 45 per cent by 2060.

Due to this rise in demand, sand mining has increased across the globe, often including unregulated and illegal operations. Extraction is now occurring faster than the rate of natural replenishment, a process that can take thousands of years. This is known as the ‘sand gap’.

While sand mining on a local scale can provide employment and  raw materials needed for development, the sheer scale of extraction in many parts of the world has considerable, cumulative, negative environmental effects if it is not carefully managed. 

Sand used for construction in many countries is often sourced from rivers and marine environments; however, sand also plays an essential role within these natural systems, supporting biodiversity and providing resilience to erosion and flooding.  The value of sand in these environments needs to be carefully balanced against its value as a material for development.

To outline this escalating risk, a new UN Environment Programme (UNEP) report, with contributions from BGS geoscientists, has been released. ‘’ highlights the risk posed to both on and offshore areas affected by sand mining. It also urges governments, policymakers and industry to recognise sand’s essential value, strengthen policy frameworks and apply early and coordinated interventions on sand sustainability.  The report presents 24 strategic actions that governments, industry, financial institutions and civil society can take to better safeguard sand resources.

The report, co-written by 27 experts from across the world, concludes with actionable policy measures and to support more sustainable sand management at local, regional and national levels.

This timely report and its accompanying tool highlight the global significance of sand mining while outlining the challenges and risks faced by the sector. We hope that this report will serve as a catalyst for policymakers, encouraging the development and application of more robust governance of sand mining. At the same time, the report aims to improve public understanding of the true value of sand. Ultimately, it should support the adoption of appropriate alternatives, reduce consumption and minimise the negative impacts associated with sand extraction.

Tom Bide, minerals geoscientist at BGS and report co-author.

Further reading

• Living in a world made of sand
• Good practice for sand mining

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

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’s 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’s 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’s 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’s .

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

Every city has a story hidden beneath its surface, shaped not just by people but by ancient landscapes and geological forces too. Under our streets, buildings and parks lies an unseen subsurface that has a major influence on how our cities function, grow and adapt.

On World Cities Day, we are highlighting urban geoscience — the study of the ground beneath our towns and cities — and why understanding this hidden world is essential for building safer and more resilient urban environments.

What is urban geoscience?

Urban geoscience helps us to understand the geology and both the natural (for example, ancient river valleys and glacial deposits) and human-made features (for example, old mine workings) beneath our cities. This knowledge helps planners and decision makers to more safely utilise the subsurface — for example, for water, energy and — while avoiding any challenges caused by the complex and sometimes unpredictable geology beneath our feet. As cities develop, urban geoscience offers the insight needed to mitigate risk and plan with confidence.

Examples of how British cities are influenced by geology

There are countless ways in which geology influences the evolution of our towns and cities. Here are four examples from around Britain.

London: shrink–swell clay and the changing climate

Much of London is built on the . This unit has clay-rich deposits that expand when wet and shrinks when dry, a phenomenon known as shrink–swell. This movement can cause cracks in buildings, damage roads and disrupt underground utilities.

With climate change, hotter and drier summers followed by intense rainfall are worsening the effects of shrink–swell. The BGS GeoClimate dataset models how these risks may change over time, showing areas most likely to experience future subsidence. Such modelling can allow for preventative or mitigative steps to be put in place to alleviate the effects of the hazard on property and infrastructure.

Glasgow: mining and geothermal energy

Glasgow sits on the Carboniferous-aged and the coal mined from beneath the city powered its industrial growth. The old mine workings have left voids in the subsurface that can collapse and, if the collapse is close to the surface, cause subsidence. However, if potential issues are known, preventative measures can be put in place to reduce the risk.

The BGS Mining Hazard dataset helps identify areas where past underground mining might pose a risk, supporting safer planning and development. Old mine workings are also providing new opportunities as warm water in flooded mine workings can be used to supply low-carbon heat and hot water to offices and homes, turning a legacy of coal mining into a .

Truro: radon risk from granite

Truro in Cornwall is a city built on Carboniferous to Permian-aged granite intrusions, which were formed when molten rock slowly cooled deep underground. Granite contains small amounts of the radioactive element uranium, which naturally breaks down (via a series of intermediate, unstable elements) over millions of years to produce radioactive .

In enclosed spaces like homes and offices, radon may build up to levels that pose a health risk, with prolonged exposure to elevated levels of radon increasing the risk of lung cancer. For most people, the risk of developing lung cancer from exposure to radon remains low. However, the advises you to test your home if you live or work in a radon affected area and there are several methods of reducing high radon levels in buildings.

Cornwall is just one of several areas around the UK were radon gas needs to be considered. The BGS/UKHSA Radon Potential dataset shows where elevated radon levels are most likely, showing where testing and mitigation are needed around the UK to make homes safer.

Cardiff: complex ground and urban redevelopment

The combination of river sands and gravels, glacial deposits and rocks of the Triassic-aged beneath the city of Cardiff affect drainage, groundwater flow and how easily the ground can be built on. As the city continues to grow and redevelop, understanding the subsurface is key for managing groundwater, avoiding subsidence and planning safe infrastructure.

The BGS 3D urban geology model for Cardiff helps to visualise the deposits beneath the city, while the BGS Civils dataset provides practical information on ground stability, excavation difficulty and chemical risks to construction materials.

Every city around the world is shaped or influenced to some degree by the rocks that lie beneath its foundations, a changing coastline along its shore or the risks posed by geohazards such as earthquakes, landslides or radon. As cities continue to grow and face new challenges, from a need to become climate resilient to an increasingly crowded subsurface, understanding the ground beneath them becomes more important than ever.

Urban geoscience connects the past with the present, helping us build cities that are not only functional but also resilient.

Artificial ground is found throughout the country in a variety of places, for example:

• railway and road cuttings and embankments
• foundations under buildings
• the waste and voids from surface and underground mining
• roads
• landscaped parks and golf courses

BGS has been creating national geological maps for nearly 200 years and often these maps are the only record of ground being altered by humans.

We are in the process of developing new methods for capturing and representing artificial ground information and we want to ensure that this is as useful and beneficial as possible to the stakeholder community.

Why do we want your feedback?

The aim of this survey is to gain an understanding from you, our stakeholders, about the types of data that are used regularly, why you need that data, and what decisions are made using the data. Mapping of artificial ground is not easy and everyone treats these deposits differently. By providing a standardised method of collecting and displaying artificial ground data there is significant potential to improve the communication of these features.

Interested in getting involved?

We have put together a short survey that aims to capture your thoughts and processes when working with artificial ground data. We value your input and would appreciate you completing this short questionnaire, providing as much context as possible.

Survey deadline extended to 28th November 2025.

North Lanarkshire has an industrialised past, including a significant coal mining legacy. Created by BGS alongside WSP UK and North Lanarkshire Council (NLC), the new coal mine gas risk decision-support tool helps to provide a preliminary risk assessment of coal mine gas emissions in North Lanarkshire. The tool utilises publicly available data and information from BGS and the Mining Remediation Authority on the subsurface to inform an instant risk zone rating for any 50 × 50 m grid cell within the North Lanarkshire area.

The tool is now live and being used by NLC to identify areas at potential risk of coal mine gas emissions and communicate them to relevant planning applications for new building or housing developments, helping to manage the risk.

After two years of research and development, we are pleased that the coal mine gas risk decision support tool is now live. It is underpinned by data and geoscience and enables NLC to identify and communicate potential risks so that these can be managed by planning applications for new builds.

We will continue to update and enhance the tool and hope to be able to expand it to be used by other councils across Scotland in the future to help manage risk.

Darren Beriro, principal geoscientist at BGS who led the development of the tool.

The new tool provides information about the risk of mine gas emissions on land across North Lanarkshire, helping inform development decisions and planning applications. By giving consistent, accurate information, the tool avoids the need for additional investigations where there is a negligible risk and allows development to progress more quickly. Where there is an increased risk from mine gas, the tool helps direct developers to expertise, advice and support on the actions required to address the risks and put in place controls to allow the development to progress.

Mark Findlay, pollution control and public health manager at North Lanarkshire Council.

In addition to the best available data from the BGS and MRA, WSP UK have developed Risk Zone Advisories within the tool and it is the combination of these items that enables NLC to consistently and efficiently screen and communicate preliminary risks to planning applicants and developers.

We are excited to see the tool in use after a long collaborative effort and hope to introduce it across other areas with significant coal mining legacy.

Aliyssa Glen, principal consultant at WSP who led the development of the tool within WSP.