Publications

Commercial oil rates are not easy to attain in reservoirs with permeability less than 5 mD. The challenges in the K-Field are low permeability with high reservoir rock strength and it is categorized as a high temperature reservoir (320 degF). Selection of the best development scenario in the K-Field, located onshore in the Malacca Strait Block, Indonesia has been undertaken continuously since 2004. Development was started using a vertical well with a conventional, perforated cased-hole completion. The development scenario was continued by drilling highly deviated wells using slotted liner completions to improve production deliverability. In 2007–2011, seven wells were drilled with hydraulic fracture-stimulation , which resulted in improved production results. The oil production increased by a factor of four compared with the best performing unstimulated wells, with an average initial rate of 359 BOPD and oil cumulative of 264 MSTB. The fracture stimulation has been the most successful technique applied to date to maximize the oil rate and recovery per well, with an 86% success ratio. Although hydraulic fracturing is not a new technique in fields with low permeability in Indonesia, the integration between fracturing design and geomechanical modeling is a relatively new concept being adopted. One of the challenges with hydraulic fracturing in Indonesia is understanding the stress anomalies due to complex geological settings and applying this data to optimize the frac design. The fracture geometry strongly depends on the reservoir characteristics and geomechanical properties. It is essential to have detailed knowledge of petrophysical and geomechanical properties of the reservoir and surrounding formations. The success of the key fracture stimulation in the K-Field was a tailored data acquisition program, followed by petrophysical analysis and geomechanical modeling, resulting in well founded fracture designs. For every fracture treatment, a Mechanical Earth Model (MEM) was constructed, based, in particular, on high quality full waveform sonic data from a recently introduced sonic tool, which provided unique geomechanical measurements. The MEM gives information to optimize our hydraulic fracture-stimulation, especially for initial design and treatment design. All the detailed knowledge has been used to increase our confidence for hydraulic fracturing stimulation. At this time, the study of hydraulic fracturing is continuing with improvements to obtain the optimum field development and production in the K-Field.