INTEGRATION OF SEQUENCE STRATIGRAPHY AND SEISMIC ATTRIBUTES FOR DE RISKING OF X FIELD IN THE NIGER DELTA

ABSTRACT

In existing hydrocarbon basins around the globe today, hydrocarbon reserves are increasingly becoming more difficult to find, hence better understanding and robust risking of target reservoirs is needed to achieve optimized exploration and production. This work studied x field to generate up-to-date maps and identify new near prospects and re-assess the resource volumes. Integration of seismic data, well log data and other subsurface data was employed across the various subsurface disciplines. Four reservoirs were mapped from the well correlation carried out across the Seven wells in the NE-SW Direction. Depositional environment was reconstructed using well log information and other available geologic information. A conceptual model was generated from gamma ray log motifs in combination with the neutron-density trend. The depositional environment was interpreted to be marginal marine. Petrophysical analysis and property modelling show that the reservoirs have porosity values that range from 22-30%, and water saturation ranges from 17-57% for various Reservoir Intervals. X field holds great abundance of sand, enabling reservoir connectivity across the field. The trapping configuration is a four-way closure in the shallow reservoirs and fault dependent (2-way) closure in the deeper reservoirs. The closures are products of rollovers anticlines related to growth faults. Two hydrocarbon bearing reservoirs were identified and mapped. Base-case estimated STOIIP vary between 5MMBO and – 90 MMBO. It is recommended that a base case volumetric estimation is carried out on the gas bearing reservoirs and that all generated depth maps be used for static modelling.