A methodology has been developed that, in conditions of limited geological and production data, ensures the integration of petrophysical, geological, and hydrodynamic models as components of a permanent 3D model, establishing physical relationships between parameters that describe the entire system.
In the proposed method, the modelling is based on the results of the interpretation of continuous shale volume and porosity curves. Based on the analysis of core data, the multi-vector physical correlations with other parameters are made. To distinguish the reservoirs and non-reservoirs, the cut-off values of shale volume are defined; to exclude tight reservoirs with no filtration, the cut-off values of porosity are set. Using the Winland R35 method the radius of the pore throat is computed, allowing dividing the reservoirs into classes. For each class of reservoirs, the permeability vs porosity dependence is determined, and the Wright-Woody-Johnson method allows deriving equations for the bound water content. A system of configured workflows has been developed and allows automating re-modelling and simplifying its history matching.
This technique was successfully applied to several 3D models of gas condensate fields, which, with a significant drilling level on the areas and a long development history, are characterized by limited geological and production data. Workflows System together with the proposed approach allowed simplifying the history matching process by splitting it into several stages. At each stage, depending on the type of input data, various parameters were matched (production, reservoir and wellhead pressures, etc.). Due to cross-functional correlation of all components, the model has significantly reduced the uncertainty parameters and allowed a detailed history matching of the development history for the entire well stock. The results obtained were tested by several geological and technological measures, including drilling new wells, and showed high convergence with the forecast indicators.
The proposed approach to modelling and history matching in conditions of limited geological and production data allows:
ensuring integration and correlation of petrophysical, geological, and hydrodynamic models as components of a permanent 3D model;
automating and simplifying the modelling, history matching, and updating a model;
improving the quality of parameters’ matching results.