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The Paleocene/Eocene age 1st Eocene Reservoir is the shallowest producing interval of Wafra Field in the Partitioned Neutral Zone (PNZ), Saudi Arabia and Kuwait. Characterization of this heavy oil reservoir is challenging due to observed variations in oil viscosity, heterogeneity related to complex mineralogy, a possible dual porosity system, and the presence of fractures at varying scales. This case study of the 1st Eocene reservoir characterization in the steam flood pilot area will improve our understanding of the range and distribution of formation properties which is critical for management of the current pilot project. This study presents several aspects of an integrated approach to characterize the 1st Eocene reservoir. The approach includes the quantification and distribution of the evaporite minerals and porosity, analysis of a possible dual porosity system, and evaluation of permeability using a new porosity partitioning technique. Data used in this study includes conventional open-hole well logs, borehole images, nuclear magnetic resonance (NMR) logs, Elemental Capture Spectroscopy (ECS) logs, formation pressure measurements, and routine core analysis. The porosity partitioning model allows the core porosity-permeability relationship to be reproduced from logs by incorporating dual porosity information. The integration of NMR logs and image logs used in the porosity partitioning model provides a well log based permeability that has a good correlation with core plug data.