In deepwater prospects, reservoir connectivity is often the largest uncertainty for defining recoverable reserves. As no single measurement provides a complete solution, it is desirable to combine multiple methods to address this risk. Traditional geochemical measurements have been coupled with downhole fluid analysis (DFA) measurements to demonstrate compartmentalization and to provide better screening for connectivity. DFA helps uncover compartments by looking for density inversions higher density fluids higher in the oil column) and by identifying discontinuities in fluid properties. To identify compartmentalization, it is essential to differentiate between discontinuous fluid profiles versus continuous or smoothly varying profiles, which are typical of connected reservoirs. A variety chemical analytes can be used to explore connectivity including methane, asphaltene, and isotope analysis. In this paper, fluid profiles are examined by a variety of measurements. Different fluid data streams are shown to be sensitive to different attributes enabling several analysis methods to explore sealing barriers. The analysis of asphaltene gradients by DFA is now known to provide an excellent method to interrogate black oil columns. Case studies are shown to provide indications of connectivity; risk factors are also discussed along with the integration with pressure measurements.
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