As global energy demand continues to rise, continued investment in oil and gas will be critical to keep pace. Recent frontier basin exploration, particularly in deepwater basins in Namibia, Côte d’Ivoire, Guyana and Brazil, have yielded high-impact discoveries. However, these settings demand identification of large prospects to justify high drilling and development costs. In such cases, quantitative interpretation techniques play a critical role in de-risking prospects and reducing exploration risks.
The deepwater Zambezi Delta Basin in central Mozambique remains largely underexplored with historical exploration focus limited to onshore fields (e.g. Pande and Temane) and the shallow shelf. In 2017, Viridien acquired over 15,000 km² of 3D multi-client broadband seismic data (Figure 2) imaged with advanced pre-stack depth migration (PSDM) using full-waveform inversion (FWI) for velocity model building to de-risk exploration and provide high-resolution subsurface imaging in the basin (Figure 1). Emphasis was placed on preserving amplitude-versus-offset (AVO) behaviour to support attribute analysis. Key plays include the Upper Cretaceous basin floor fans, Paleocene hybrid channel systems and the Tertiary channel systems related to the Zambezi Delta system. Here, we look at how we can assess prospectivity in a frontier basin using AVO screening techniques.