Hydrocarbon reservoir delineation using simultaneous and elastic impedance inversions in a Niger Delta field

Abstract The global energy demand is increasing while production from mature fields drastically reducing consequently, oil and gas industries are expanding activities into more challenging areas. inability of the traditional seismic data to properly delineate hydrocarbon reservoirs subtle features in ‘Sandfish’ field located offshore, Niger Delta informed use simultaneous elastic impedance inversion. derived volumes inversion would reduce risk, enhance discovery optimize development plans study area. Four (Sfn) wells (Sfn-01, Sfn-02, Sfn-04 Sfn-05), check-shots 3D five angle stacks (6–12°, 12–18°, 18–26°, 26–32° 32–42°) were used study. Low frequency (0–2 Hz) models generated interpolation high-cut-filtered compressional wave velocity log (P-sonic), shear (S-sonic) density guided by interpreted four horizons. low broaden spectrum also served as constraints. partial varying 6–42° simultaneously inverted using Jason’s Rock-Trace® software which iterated trial inversions until model sufficiently matched data. near (6–12°) far-far (32–42°) compared with This was carried out determine effectiveness volume delineating reservoirs. P-impedance (Z P ), S-impedance S (ρ), lambda-rho (λρ), mu-rho (µρ), Poisson’s-ratio (σ) reveal vertical lateral continuity identified (K01, N01 P01) at 2179 m, 2484 m 3048 respectively. delineated showed good match sand tops away well control validated a blind test. cross-plot Z gave correlation coefficient 86% indicative high quality will exploration risk. plot reflected 82% indicating that this method could be adopted other limited similar geological setting. Hence, has shown efficacy can help locate optimum region for wells.