This study aims at estimating potential future oil discoveries in Brazil by looking at the creaming phenomenon in past exploration trends. We apply a top-down modeling approach as fields' reserves are not disclosed. This study focuses on the four sedimentary basins which concentrate 95% of the Original Oil-in-Place (OOIP) discovered: Campos, Santos, Reconcavo and Potiguar. This work considers the 1P and 3P reserves to create a proxy for the volume of discoveries. Findings indicate potential to increase reserves by improving the recovery factor as well as by yet-to-find discoveries. We evidence such discoveries can be very sensitive to the function chosen to fit the creaming curve but also to the uncertainty in reserves estimates. Given the limited literature in Brazil concerning its exploratory potential, the creaming curve approach plays a vital role due to its relative simplicity and low data requirement. The methodology proposed in this study can be especially useful for many non-OECD countries where the availability of field-level data is limited.