Incorporation of fault properties into production simulation models of Permian reservoirs from the southern North Sea

Abstract

AbstractReservoir compartmentalization is one of the key issues that affects the development and production phase of gas fields. To improve prediction of the effects of compartmentalization on production, a new method has been developed to allow petroleum engineers to incorporate geologically-reasonable fault rock flow properties into upscaled dynamic reservoir simulation models. The first stage of the workflow is to estimate the permeability and capillary characteristics of fault rocks within the field. These data are then combined with estimates of fault rock thickness, derived from outcrop studies, to calculate transmissibility multipliers to take into account the impact of faults on fluid flow within the dynamic model. Our method differs from most others in that we have attempted to account for the two-phase flow properties of fault rocks in the dynamic models from producing reservoirs. Application of the model to real field examples provides far faster history matching than has been achieved previously. In addition, taking into account the multi-phase flow properties of fault rocks explains production behaviour that previous models could not. Although, the focus of this study has been on the Southern Permian Basin in the North Sea, the same approach could be applied to other areas.