THE STUDY OF THE MIGRATION PROCESSES OF ELEMENTS IN THE GEOSPHERE THROUGH NATURAL ANALOGUES IS ONE OF THE BEST WAY TO VALIDATE THE CALCULATION TOOLS DEVELOPPED TO PREDICT RADIONUCLIDES TRANSFERS ON LONG TIME PERIODS.
IT HAS FOR OBJECTIVE TO QUANTIFY THESE PHENOMENA WITH SLOW KINETICS, TO SHOW THE THOROUGHNESS OF THE MECHANISMS TAKEN INTO ACCOUNT IN THE MODELS, OR TO PERMIT THEIR MODIFICATION, IF NECESSARY.
THE PRESENT STUDY IS BASED ON THE INTERPRETATION OF THE DATA OBTAINED BY THE BRITISH GEOLOGICAL SURVEY ON DIFFERENT "NATURAL ANALOGUES" SITES IN THE U.K.

1. MODELISATION OF THE ELEMENTS TRANSFERS IN THE ARGILLACEOUS SEDIMENTS FROM LOCH LOMOND.

2. PRE-MODELISATION OF NATURAL ANALOGUES SITES ON THE FIRST SETS OF DATA GATHERED BY THE BGS.

3. INTERPRETATION THROUGH MODELS OF THE COMPLETE DATA SETS : TRANFER IN CRISTALLINE ROCKS (MATRIX DIFFUSION), TRANSFER IN CLAY QUATERNARY SEDIMENTS, FOR EXAMPLE.