ABSTRACT The paper presents an application of recently developped geostatistical conditional simulation techniques to the modelling of heterogeneity in a complex turbiditic reservoir. Heterogeneity is mainly controlled by the distribution of sandstones embedded in laminated facies. Channels and lobes account for most of the production. Their frequencies and geometries are critical factors that affect reservoir connectivity, hence oil recovery. The combined used of flexible stochastic techniques allows generating realistic 3D models of this complex architecture. The modelling strategy is multi-steps, with first a geologically constrained generation of facies distributions, and second, simulations of permeability variations within the previously generated facies distributions.