This server will be unavailable between 16:00 on Friday 25th July and 09:00 on Monday 28th July and again between 16:00 on Friday 1st August and 09:00 on Monday 4th August while we carry out essential system updates.
We apologise for the short notice and for any inconvenience.
The Lexicon of Named Rock Units database provides BGS definitions of terms that appear on our maps and in our publications.
For further information or comments on the Lexicon of Named Rock Units, please contact Dr Tim McCormick.
To use this dictionary, please enter the name or part-name of the rock unit that interests you; then click the "Submit Query" button. Alternatively, you can search by Computer Code or Preferred Map Code, if these are known. Searches may also be specified and performed on the basis of the Maximum Age of the rock unit or the Status Code. Searches can be carried out using one or any combination of these criteria.