Discernment of Cavern Networks & Dissolutional Sinkholes on a Miocene Carbonate Platform in Central Luconia Province

Karst in carbonate rocks could contribute to the improvement of the porosity and permeability of a hydrocarbon reservoir. However, it could pose a geological challenge and be hazardous for subsequent drilling and production activities. Karst distribution and patterns are unpredictable because its formation is subjected to the influence by the depositional setting, sea level fluctuations, and the influence of the meteoric water on the carbonate rocks. Some carbonate gas fields in the Central Luconia Province have experienced unpredicted high-water production and early water breakthroughs during the field’s gas production phase. The assumption was that one of the few contributing elements to the unpredicted early water breakthrough was the strong aquifer beneath the gas interval and high heterogeneity within the carbonate reservoir. This study aims to provide a comprehensive interpretation of the carbonate interval of the AB08 field by producing karst maps, characterise the different karst on the AB08 carbonate platform, and lastly, producing quantifiable 3D geobody karst grids which will be input into the static and dynamic models.