The recovery strain method of stress determination involves a number of assumptions and idealizations that raise questions about its general applicability. Issues of particular concern are gradual removal of stresses during core retrieval, the effect of pore pressure and temperature, working with deviated wells, and observed expansions and contractions in the same core. A procedure is outlined that takes into account the effects of pore pressure, temperature, and anisotropies in the core and can be applied to core from deviated wells by making measurements on appropriate axes. Equations derived in this study for calculating stresses from recovery strains include the effect of gradual unloading experienced by core during its retrieval. Application of the equations to field data show that the effect of gradual unloading is small in most cases but can be significant under certain conditions. One particularly interesting result of the theoretical analysis is that for high Poisson's ratios and deviatoric stresses, core will actually contract. Favorable comparisons of stresses determined by the recovery strain method to those obtained from hydraulic fracturing and overcoring at sites in Colorado, Oklahoma, Nevada, and the North Sea support the practicality of this method.

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