Several aspects of coupling between reservoir fluid flow and geomechanics deformation are examined, namely accuracy, adaptability and running speed. Four different widely used time-coupling techniques (full, iterative, explicit and pseudo) are reviewed and evaluated based on these three aspects. This paper focuses on the iterative time-coupling approach with detailed discussions on how reservoir porosity and absolute permeability are changed with geomechanics. In addition, dual-grid coupling techniques are evaluated with respect to memory storage and CPU requirements for a large field problem. A SAGD example compares fluid-flow and geomechanics results obtained from pseudo coupling versus iterative coupling approaches. A waterflood example shows how iterative time-based coupling method is combined with the dual-grid coupling method to improve CPU speed. In a compaction example where modelling of country rock is crucial, the dual-grid coupling method avoids non-conforming grids when local grid refinement is used around a producing well. Keywords: full coupling, iterative coupling, explicit coupling, pseudo coupling, grid coupling, reservoir porosity, true porosity, absolute permeability, geomechanics, deformation.
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