Seismic Driven Lithofacies Integration for Geological Model Infilling in a Deep Offshore Turbiditic Field Case Study

Abstract

This paper describes a workflow implemented for the geological model infilling of turbiditic channel complexes driven by lithoseismic Pseudo-VClay (PVClay) to constrain the facies modeling. The key challenge is to conciliate seismic resolution and required geological resolution to represent heterogeneities that allow an accurate prediction of fluid flows. For this purpose, facies modelling has been achieved by using two successive steps. The first one is based on a geostatistical proprietary method named Truncated Geophysical Estimation (TGE) using the PVClay attribute to guide the initial Lithofacies Associated Facies (LAF) positioning. The second step of the facies modelling sequence corresponds to a Truncated Gaussian Simulation (TGS). It distributes AF in a stochastic way within each LAF defined at the previous step. Thanks to this second step of facies modelling it becomes possible to introduce geological heterogeneities at the fine scale required by the vertical resolution of the reservoir model. The advantage of this workflow is that the geological model infilling is conditioned by seismic data and accurately ties the well information. In addition, it can be updated easily in order to integrate new well data. It is also interesting to point-out that the preliminary dynamic simulation delivered by this model allows obtaining a good match with early production data.