Publications

The development of the Kerendan Field has been reinvigorated by the acquisition of 3D seismic data which significantly improved the reservoir characterization of heterogeneous and complex Berai carbonates, long considered a major challenge and uncertainty to the project since its discovery in 1982. During 2012 � 2013 drilling campaign various suites of Borehole Image Logs (BHI) were acquired. New 3D seismic data was also acquired in 2017 and resulted in a major improvement on reservoir characterization and definition of gas storage � delivery system in the Kerendan Field. An integrated geomodelling study was performed to link the 3D seismic interpretation and BHI image log analysis with core - petrophysical analysis to characterize the reservoir units and its distribution within the carbonate platform. The integrated geomodelling study was established based on several important factors that influences the reservoir distribution pattern in the carbonate platform and subsequent fabric-selective diagenesis that promotes development of secondary porosity, in following order; (1) Depositional Elements (DE) belts, (2) BHI facies association and reservoir quality profile, (3) cyclical stacking pattern related to deepening-upward trends and marked by development of Irregular Laminated Platestone with vuggy porosity on top of the cycles. The study results highlights the main gas delivery system in the Kerendan Field associates with extensive layers of remobilized bioclastic fragments, in form of grainstones and packstone-rudstone units which commonly developed within the Reef Complex DE belt. Subtle bioconstruction features in the platform center area such as the Bioherms DE may form additional gas storage system which manifest into significant volumetric value if developed as vertically stacked compounds. Rate Transient Analysis of current production wells indicates that stabilized flow properties in surrounding wellbore environment of the production wells are strongly related with relatively low permeability matrix (0.03 � 0.05 mD). The variations observed on production wells performances attributed mainly to the reservoir heterogeneity. The key to achieve best well deliverability is by identifying and intersect the sweet spot zone that contains interlayered grainstone facies which serves as the best quality gas delivery system and connectivity to vuggy Bioherm geobodies as the gas storage system. Understanding the sensitivities and uncertainties inherited with aforementioned factors may help to build a reliable 3D geomodel for estimating the potential resource volumetric and establishing effective field development plan.