EARLY IDENTIFICATION OF RESERVOIR COMPARTMENTALIZATION BY COMBINING ARANGE OF CONVENTIONAL AND NOVEL DATA-TYPES

Reservoir compartmentalization (vertical and lateral) is often a major uncertainty at the field appraisal stage, impacting important investm ent decisions. Unfortunately the most definitive compartmentalization data (dynamic production data) are not usually available so early in f ield life. This paper illustrates how early indications of compartment alization can be achieved by integrating various types of conventional and novel data. Using an example from the Ross oilfield, U.K. Contine ntal Shelf (UKCS), we demonstrate how integration of oil compositional data (molecular maturity parameters, gas chromatography [GC] fingerpr inting, pressure-volume-temperature [PVT] data) with pressure, well te st, and fault seal analysis revealed the presence of several sealing f aults, and thus enabled the field to be described in terms of its like ly segmentation. Vertical compartmentalization was investigated using a combination of oil geochemistry (maturity, GC fingerprinting), water composition (residual salt analysis), and high-resolution stratigraph y, revealing a continuous shale that has a lateral extent of >5 km; it divides the reservoir into two main layers. The results of this study helped to decrease uncertainty in field development planning. The key message is that there are many tools available to aid in assessing co mpartmentalization, but individually they each only give part of the p icture. It is therefore important to use several tools in combination.