Cross Disciplinary Workflow to Determine Acceptable Overpressure within a High Pressure Sour Gas Field

The study reviewed in this paper aimed at determining the maximum injection pressure, together with injector location, in order not to damage the cap rock sealing efficiency. A cross disciplinary workflow was set up, involving geoscientists, geomechanical engineers and reservoir engineers. It consists of four major steps 1. Determination of the initial sealing conditions and potential weak points of the structure 2. 1D MEM (Mechanical Earth Model) as a first estimate of the maximum injection pressure 3. Elastoplastic framework of the carbonate reservoir matrix 4. 3D MEM (Mechanical Earth Model) to refine the 1D MEM findings This workflow enabled us to identify two main weak points of the reservoir • The apex of the structure, were a maximum pressure increase was defined. As pressure can rapidly propagate in fractures and karst, this maximum pressure increase was imposed at any well location • The border faults, and as a consequence no injectors were located in the vicinity of these faults and reservoir models were checked to ensure that no pressure increase would happen at these locations.