Example of a 1:100 000 lithological map available in the BRGM atlas
In order to determine the need for construction materials induced by the major French Guiana construction projects to come and to ensure that the active quarries can supply them, the Guiana DGTM asked BRGM to conduct a survey to list all of the projects, to assess the amount of materials needed to carry them out, to define the consumption areas and, finally, to assess the available reserves.
The BRGM study identified three main consumption areas (Presqu'île de Cayenne, Bas-Maroni and Kourou) and two emerging areas (Haut-Maroni and Saint-Georges). These five areas are expected to require around four million tonnes of aggregate over the next ten years.
The inventory of resources and reserves shows that the active aggregate-quarries in French Guiana will be sufficient to meet demand for many years to come, provided that operations are rigorously supervised and that extensions are granted for quarrying the materials.
In order to make it easy for professionals to use the inventory, BRGM drew up 15 lithological maps on a scale of 1:100 000, with a twofold objective of:
- presenting the spatial distribution of aggregate reserves in relation to the different consumption areas;
- proposing new sectors to be targeted for quarrying, to meet possible new needs (diminishing reserves or new work sites).
Using the results
These results provided the public authorities with a long-term view of the evolution of aggregate reserves in French Guiana. The amount and type of information will facilitate better management of the resource and will provide input for decisions on applications to open, extend or close quarries. The work will be used to support the development of the new Regional Quarry Master-Plan for French Guiana, which is to be undertaken in 2022.
The study served both to update the quarry data and as a preliminary study for the next regional master plan for quarries. The map atlas allows us to adapt to changes and new expectations, particularly with regard to the strong demographic growth in French Guiana. Intermediate meetings were held at the initiative of BRGM and allowed us to track the progress of the study on a regular basis. We very much appreciated this collaboration and are very satisfied with the results of the study.
- Departmental Authority for Inland and Marine Areas