Seismic imaging of a carbonate reservoir; the Dogger of the Villeperdue oil field, Paris Basin, France

The Villeperdue field produces oil from a thin and heterogeneous carbonate reservoir of middle Jurassic age. Despite the presence of 150 wells, the production of this field (about 9000 bbl/day) is decreasing continuously and forecasting the productivity of new wells remains hazardous. In a joint effort by four operators, a contractor and a research institute, advanced seismic methods including 3D, 2D-3c (3 components), 2D-HR (High Resolution) and 3c-VSP (borehole seismic) were combined to improve reservoir characterization and define methods for revitalizing exploration in the Paris Basin. The combination of continuous spatial sampling, such as that obtained in 3D, and a Vibroseis emission adapted to the high-frequency attenuation, such as that used in 2D-HR, supplied useful information about the reservoir heterogeneities which cannot be provided by correlation of the well data. In this way thickness, lateral porosity variations and small faults (throw <10 m) were successfully detected, making it easier to select the locations of new production wells.