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Integration of all available data in reservoir characterization is critically important. 2D mapping is a reliable and robust technique that allows integration of multiple secondary data, including geological and geophysical surfaces and maps, to generate realistic summaries of reservoir quality at each location in an area of interest with an associated measure of uncertainty. This is achieved in 2D mapping with a more straightforward implementation, requiring significantly less time and fewer resources than three‐dimensional modelling. In this paper, we propose an approach for the empirical calculation and optimization of differential compaction maps by leveraging existing well control for the use in 2D mapping. Success of the proposal is demonstrated through tests of accuracy, precision and fairness of the local uncertainty distributions for 100 new stratigraphical wells drilled in the Christina Lake and Kirby East area.

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Summary When considering the seismic response in Cagniard’s problem, where a plane interface separates homogeneous, isotropic media, high‐frequency asymptotic representations are known to break down at critical angles, where head waves and reflected waves interfere. Formulae have been derived to correct this, to be used in conjunction with more standard asymptoti c expressions. We present formulae that are more generally applicable, as they account for the contribution of leaky waves, which can be asymptotically significant. The importance of leaky waves is shown to occur for strong contrasts in velocity across the interface. We therefore arrive at a series of approximations, based on a ray approach, that can be used to model a single interface or a system of homogeneous layers in an efficient manner.

Relating subsurface stress to velocity anisotropy can provide quantitative insight into the effects of reservoir production. Rock-physics models using effective medium theory for unconsolidated sands can be built to establish this link, although empirical corrections are often required. In pursuit of this goal, fractional changes in elastic moduli have been related to fractional changes in stress through a perturbation analysis of the extended Walton model. The stress path considered was composed of isotropic loading followed by an arbitrary stress perturbation. The coefficients derived are dependent on granular elastic moduli and the proportion of grains with no-slip contacts but are conveniently independent of strain and porosity. A modification of these relationships has been introduced using an anisotropic stress-dependent coordination number, whose parameters can be derived from isotropic moduli-stress experiments. The inclusion of an anisotropic coordination number improved the model’s fit to experimental results of unconsolidated sands subject to anisotropic loading.