De-risking Reservoir Quality and Presence through Seismic Inversion and Rock Physics Analysis in Brazil's Pre-salt Carbonates

and rock facies with a profound effect on permeability; the presence of non-reservoir rocks; limited seismic detectability of fluid signal in the rigid carbonates; and seismic data quality issues caused by the complex heterogeneous overburden. In order to address most of these challenges an integrated quantitative seismic interpretation workflow as been applied through detailed well data analysis grounded by calibration on the core and thin section scale, followed by rock physics modelling, interpretation of carbonate and non-carbonate facies, AvO-inversion, and facies-based reservoir characterization – all integrated to enable generation of 3D reservoir property cubes. The workflow also included fluid evaluation, forward modelling, and direct hydrocarbon detection (DHI) in areas where fluid signal may be detectable on seismic.The study’s interdisciplinary data reconciliation also helped improve our understanding of geological factors that control deposition of pre-salt carbonates, their elastic properties, and seismic response.