Lithology and fluid discrimination using rock physics-based modified upper Hashin–Shtrikman bound: an example from onshore Niger Delta Basin

Abstract The Ozifa reservoir is proven that cuts across the Northern and Greater Ughelli depo-belts of Niger Delta Basin. This possesses heterogenous character southward field, making elastic properties, lithologies fluid types difficult to describe accurately. In this study, rock physics template was applied porosity acoustic impedance (AI) crossplot clusters illustrate rock–fluid relationships using modified Hashin–Shtrikman upper bound, Voigt bound Reuss lower as an input in template. Values were used lithofacies classification parameters for discrimination types. Our result showed line when porosities (φ) domain discriminated gas-filled reservoirs from brine filled shale effectively. Similarly, results clear separation shale, heteroliths with gas bearing sand, which not plausible conventional petrophysical analysis. approach successfully analysing relationship different well locations serves a model successful prediction lithology types, major requirement determining effects geological variables such sorting, clay distributions on connectivity optimum production time-lapse (4D) seismic interpretation.