f Conditioning the models with … uncertainties

The geomodelling technique has become the principal tool for geological representation of the subsurface for the last 10-15 years. It has been subject to an important technical and commercial development and growth and as a consequence has led also the way to a rapid evolution of reservoir modelling and the use of dynamic data. In particular the contribution from geostatistical methods has been a key factor for success. Figure 1 shows the classical streamline process from data processing/ analysis and interpretation to the geomodelling and reservoir simulation leading to the final evaluation of IHIP and production/ reserves. The interesting point to see is that many feed-back loops exist today, not only from reservoir model to geomodel but also from geomodel to different previous data processing/ analysis and interpretation steps. These feed-back loops clearly identify the need to go back more and more upstream in order to better condition the final reservoir model to the field monitoring and production history data. The practice of geomodelling and now of the feed-back loops increase the need for team integration and cross-discipline approach. One important reason for this need is the presence of uncertainties within the different type of data generally due to the scarcity and the quality of the acquisition. Processing and interpretation could sometimes become so difficult that only data integration could somehow helps to relieve the situation.<br>