- © 2006 Geological Society of South Africa
The geometry of the E-BD reservoir is such that that the thickness of the oil-leg and the water-leg are usually below the seismic limit of separability. Seismic amplitudes from a 3D survey have previously been used to characterise the reservoir. The validity of this approach is however affected by a thin, silt-rich unit that overlies the reservoir in places. This unit has been termed abandonment facies (AF), and modifies the seismic amplitude of the reservoir-top reflection. AVO effects along reservoir-associated interfaces also influence the stacked seismic amplitude. Five boreholes intersect the E-BD channel. Log data from these boreholes indicate changes in acoustic properties across the sandstone interval. These changes also affect the amplitude of the observed seismic data. In this article, the results of a 2D modeling study are presented, which was undertaken to understand these seismic amplitude effects.