What is a geology map?
A geology map is any map that provides details about rocks, sediments, faults and a whole range of observations to do with the composition and structure of the Earth. BGS surveys geological features at 1:10 000 scale and we digitally publish our findings at this and smaller scales. The maps convey our best interpretation of what lies beneath our feet and the evidence behind the map can be derived from decades of research, countless boreholes and sampling programmes, and digital landscape analysis. Traditional survey techniques are still used, but BGS now also uses 3D modelling and visualisation to help update and improve the maps on a continuing basis.
Who uses a geology map?
Geology maps are made for a wide range of users. Some of our mapping and research is dedicated to simply understanding the Earth, the processes that modify our landscape and the role geology plays in our lives. Some users rely on our maps to work out things like resources (energy, water, minerals), construction conditions (excavations, foundations), soils and landscapes (peatlands, uplands), and hazards (flooding, landslides, contamination). We try to make maps at different scales and with different attributes so that as many users as possible can find the right map and information for their needs.
What is the geology under my house?
We have several ways for you to look at the geology beneath you. Our Map Viewers page is a good place to start, or you could go straight to our Geology of Great Britain viewer. If it’s a paper map you want to see, we recommend a visit to the BGS maps portal.
What are the different colours on the map for?
The different colours, patterns and linestyles are to show differences in rock age, rock type or some form of process or characteristic that makes the ground ‘different’ geologically from it surroundings. Many geological units have had traditional colour schemes since the earliest map made by William Smith 200 years ago. The colours and patterns allowed early mappers to show 3D geological complexity on a 2D piece of paper. The advent of digital data means that we can interrogate 2D and 3D data with a mouse click, but we retain familiar ‘colours’ and map styles so that users can see how the digital world relates to traditional geological maps.
Where can I purchase paper maps?
Where can I get digital data?
Data are typically available under licence. However, an increasing number are available for view or download. Our datasets page can provide details of the different datasets available. Each page will provide information about data coverage, prices, formats and who to contact. Many products also offer sample data downloads and user guides to help you decide if the data is suitable for you.
I don’t have a GIS. Can I still view the data?
Yes! Our Map Viewers page is a good place to start: there are links there that will take you to various apps and online services, or you could go straight to our Geology of Great Britain viewer. If you want to see more than just geology data, our GeoIndex is an online data and GIS service that covers a very wide range of geoscience research. If it’s a paper map you want to see, we recommend a visit to the BGS maps portal.
How often do you update the geological maps?
Our mapping is updated by a combination of strategic survey and ad hoc review (normally as part of our wide research activities). These generate a range of new data and corrections across Great Britain and the BGS Geology team have a year round programme of editing and updating. It can take a while to fully resolve a new area of mapping or reconstructed data, so our map revisions are published periodically (typically every two to three years).
I think the geology map might be wrong. What can I do?
We make every effort to ensure that our digital data reflects our best understanding of the geology of the UK and its continental shelf. Sometimes our interpretations need to be revised as new evidence (such as boreholes) are obtained and sometimes simple errors simply get through our quality assurance procedures. We are currently working on a web service to improve notifications of errors that have been found and corrected; we hope to make this available soon. If you think you have spotted a problem with our datasets please let us know.