Detailed Discrete Fracture Network in Support of Drilling Activities in North Kuwait Carbonate Reservoirs

Abstract

The North Kuwait Carbonate Reservoirs (NKCR) are currently under development by KOC (Kuwait Oil Company). The appraisal and development of the NKCR offer challenges such as lateral variations in reservoir quality, tight to very tight reservoirs and natural fractures with a high degree of spatial variations.The presence of open, connected fractures is one of the key elements to achieve a successful development. Also, the presence of fracture corridors increases the risk associated with drilling. Numerous fracture modelling studies have been supporting both appraisal and development strategies of the fields. This paper illustrates how small sector scale detailed DFN (Discrete Fracture Network) can support the planning and drilling activities of future appraisal wells.A series of detailed DFN models has been built around existing wells. These DFN models are based on a thorough structural understanding combined with a detailed fracture characterisation using bore-hole image (BHI) and core data around the wells of interests. In addition to the fracture characterization work, mechanical stratigraphy has been developed using E-facies and geomechanical logs. Fracture connectivity analysis has been carried out to calibrate the DFNs to the static and dynamic well data. DFN models have also been created around appraisal well locations based on the calibration with the existing wells. These DFN models are now being used to communicate with drilling in order to illustrate the potential distribution of fracture corridors in the sub-surface. These DFN models are also helping to improve the placement of the planned wells with respect to their associated risks and objectives.