Reservoir prediction offshore West Africa in deepwater turbidites of Turonian age is a difficult seismic task. The deposits are represented by clayey series cut by a great number of narrow, winding amalgamated sandy and sandy-silty channels with dramatically changing properties. Attributes and AVO analysis showed low reservoir prediction accuracy. Rock physics modeling found that the density and S-wave velocity are necessary for the reservoir sandstones separation. Therefore, three-parametric simultaneous elastic AVA inversion has been performed. Only this type of inversion is able to calculate the required elastic properties. But it uses larger incidence angles and relatively more sensitive to signal-to-noise ratio. The seismic modeling showed that the signal-to-noise ratio on the recorded seismograms is sufficient for the required elastic properties calculation. Probabilistic approach based on the Bayes concept, with probability density functions (PDF) have been used for the lithology prediction. Due to geological complexity of the series structure the deterministic approach provides lower efficiency. Reservoir probability cube was obtained from the inversion results. Lithology cube was calculated using sand probability threshold P = 0.5. Results of reservoir prediction have high correlation with well data in contrast with other methods previously used in the field.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error