This paper is a state-of-the-art review of the formulations for the different processes responsible for the transport and mixing of petroleum oil spilled in natural waters. Processes accounting for the transfer and loss of the surface oil, such as initial spreading, evaporation, dissolution, emulsification, dispersion, photo-oxidation, and sedimentation, are included. Based on the findings, a dynamic mathematical model describing the fate of spilled oil was developed. To reflect field observations, the surface oil composition in the model is allowed to vary with time as a result of weathering. Initial results for model testing are presented.Key words: oil spill, mathematical model, fate model, weathering processes.Cet article presente un examen avant-gardiste des formules relatives aux diffkrents procedes responsables du deplacement et du melange du petrole d6vers.i dans les eaux naturelles. Les procedes responsables du transfert et de la perte du petrole superficiel comme la propagation initiale, l'tvaporation, la dissolution, l'Cmulsification, la dispersion, la photooxydation et la sedimentation sont inclus. Un modele mathematique dynamique integrant les resultats de cet examen a kte dkveloppe afin de decrire le sort du petrole deverse. Pour reflkter les observations faites sur le terrain, le modele a tenu compte de la variation de la composition du petrole superficiel en fonction du temps causee par la degradation. Les rksultats initiaux des essais de modelisation sont prksentes.Mots elks : deversement de petrole, modele mathematique, modele du sort, procedes de degradation.[Traduit par la redaction] Can. J. Civ. Eng. 20, 210-219 (1993)