About two thirds of Block 32, offshore Angola, is covered with allochthonous salt bodies that complexify seismic wave propagation thereby tending to make illumination irregular and accurate imaging difficult. In the early years of exploration of this block, this prevented a good estimation of the resources and their distribution in several subsalt areas. However, in the last decade the industry has seen a dramatic improvement in subsalt seismic imaging capabilities thanks to the significant uplift in illumination offered by wide-azimuth towed-streamer (WATS) data and the improved simulation of seismic wave propagation used in Reverse-Time Migration (RTM), enabled by the increased computing power now available. In this talk we review the evolution of the imaging of Block 32 during this period: we show that, as our images improved, so did our understanding of the geology, which fed back into the model-building, yielding further improvements; and we look at the most recent advances due to full waveform inversion and image post-processing using RTM surface-offset gathers. Cumulatively, these have transformed our vision of, and confidence in, the subsalt reservoirs and allowed the Kaombo multifield development to be launched.


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