Field appraisal and development plans aim to provide the best technical solution for optimizing hydrocarbon production and require integration between various disciplines including geology, geophysics, engineering, well planning, and environmental sciences. Seismic inversion could provide one essential component for reservoir modeling in support of appraisal and development evaluations. Therefore, it is important to quantitatively assess all of the possibilities and uncertainties involved in reservoir definition and extension. A probabilistic facies-based seismic inversion method has been utilized to achieve this goal in a recent Central North Sea discovery. The probabilistic nature of the inversion allows computation of various scenarios. We categorically selected, among others, most likely, optimistic, and pessimistic scenarios based on prior knowledge and calibration at the wells. Then, we performed a statistical analysis of all of the scenarios to identify the uncertainties. We also performed a postinversion forward-modeling study to assess uncertainties that may be related to thin layers of subseismic resolution.