CHARACTERIZATION OF ORGANIC-MATTER MINERALS ASSOCIATIONS IN OIL-FIELDROCKS USING THE NUCLEAR MICROPROBE

The improvement of the oil production forecast and the recovery strate gy is closely related to a better understanding of the oil reservoir w ettability. As there is a need of a description of the spatial distrib ution of wettability down to the pore scale, new tools allow to enhanc e very fine scale wettability contrasts and to evidence the importance of mineralogy. Among them, we propose to use the nuclear microprobe a nalysis (NMA) for the qualitative and quantitative study of the organi c matter/mineral interactions i.e. the description of the reservoir ro ck wettability. NMA, field emission SEM and AFM techniques are used to image and study the mechanisms and kinetics of the sorption of the or ganic matter on model samples: the organic film thicknesses and the ma jor elemental contents (carbon and nitrogen) are measured.