The CAGEPYR project was carried out with backing from the Pyrenean Moutains Commission, and within the framework of the Pyrenees project of the French Geological Reference Platform (RGF) programme. It created a geological map of the French side of the Pyrenees from RGF data.
21 September 2020
Geological map of the French Pyrenees

Geological map of the French Pyrenees at 1:250,000.


The need

The Pyrenees Massif has not yet been covered by a regional scale map, which would allow a synthesis of a whole geological domain to be made. In order to remedy this, as part of the RGF programme, BRGM has produced a geological map of the northern side of the Pyrenees, at a scale of 1:250,000, covering an area extending from the Atlantic to the Mediterranean. This scale provides a geological synthesis of the massif, which is useful for the scientific and educational community as well as for communicating with the general public and for spatial planning needs. It is also perfectly suitable for presenting the geological context of the different sites of the national inventory of France’s geological heritage.

The results

The lithostratigraphic database of the RGF was used to enrich the details included on the map of the Pyrenees, which represents various hierarchical levels: super-groups, groups, sub-groups, formations. This choice enabled BRGM to build a modern cartographic document from the most recent data, which could represent the new concepts studied for the last 10 years on the mountain range. This work illustrates perfectly the possibilities of using RGF data to produce customised maps of the Pyrenees.

The resulting digital geological map consists of six inseparable graphic layers, in the form of vectorised data associated with an attribute table containing information on each object's characteristics. The legend, which describes the nature and age of the geological formations, has 119 coloured rectangle items. The use of RGF data, which has been validated by a scientific council, guarantees the reliability of the digital data, which has been validated by a scientific council as well as its traceability and the relevance of the geological formations represented on the map. These aspects ensure that the data intended to be used as a reference are consistent and can also be updated.

Organ-pipe rock formations at Ille-sur-Têt

This project allows us to make data open and available to users. In this way, anyone can draw on scientific knowledge to develop digital projects. We now have valuable knowledge of the ground and subsurface, and this allows us to enhance our public service mission. Our services also remain available to help develop tools to enhance the value of these data for technical services.

Romain Provost, Project Manager, DREAL Occitanie

Using the results

The digital map produced as part of this project is accessible and downloadable free of charge via web services available on BRGM's Infoterre platform and the inter-ministerial cartographic portal PICTO-Occitania.

The partners

  • Pyrenean Moutains Commission for Planning, Development and Protection
Extract from Atlas version of the map and photo of an inventory site for the geological heritage of Ariège

Extract (page 7) from Atlas version of the map and photo of an inventory site for the geological heritage of Ariège (Dreuilhe anticline).