This paper presents a forward model for subsidence predictionrnand an inversion model to calculate the reservoir behaviourrnfrom subsidence data. The forward model employsrncombinations of analytic solutions to the elasticity equations,rnwhich approximate the boundary conditions. There are onlyrnfew free parameters and consequently the calculation times arernlimited. Still, the model is applicable to a multi-layerrnsubsurface with elasticity parameters changing per layer. Therninverse problem is usually ill-conditioned or ill-posed and hasrntherefore been regularized by introducing a priori data aboutrnthe pressure field or by imposing a certain amount ofrnsmoothness. The strength of the regularization parameters arernbest determined using the model resolution of the inversionrnand synthetic cases. These also can be used to optimize thernexperimental design. Inversion of a synthetic case with arn“wrong” forward model shows the importance of obtainingrnreliable subsurface elasticity data. Without such data, thernquality of the inversion can be highly compromised.
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