At Ribemont-sur-Ancre, the Gaulish levels of soils were outstandingly well preserved under the refills from the Gallo-Roman temples. It was thus possible to take samples of deposits in bags and/or orientated blocks, from 1995 on, for an in-depth study of their differences. A global and comparative study is given here for the first time. The specificities of certain ploughed levels, occupied areas in the enclosure, or deposits placed at the same level as the human bones give clues to a more precise understanding of their environment and a better archaeological interpretation. Traduction : Margaret & Jean-louis CADOUX.