We have evaluated an innovative application of extendedelastic impedance -EEI- to integrate seismic and geomechanicsfor geomechanical interpretation of hydrocarbon reservoirs.EEI analysis is used to extract geomechanical parameters.To verify and assess the capabilities of EEI analysis forextracting geomechanical parameters, we selected a jointed,oil-bearing, shale carbonate reservoir in the southwest of Iran,and we used petrophysical data and core analysis to estimatestatic and dynamic moduli of the reservoir rock. We calculatedthe corresponding EEI curve to different intercept-gradient co-ordinate rotation angles -the chi angle,χ-, and we selected theangles of the maximum correlation for the corresponding geo-mechanical parameters. Then, combining the intercept andgradient, we generated 3D reflectivity patterns of EEI at differ-ent angles. To obtain a cube of geomechanical parameters, weperformed model-based inversion on the EEI reflectivity pat-tern. A comparison between the modeling results and well dataindicated that the geomechanical parameters estimated by ourmethod were well-correlated to the observed data. Accord-ingly, we extracted the geomechanical and rock-physicalparameters from the EEI cube. We further found that EEIanalysis was capable of giving a 3D mechanical earth modelof the reservoir with the appropriate accuracy. Finally, we veri-fied the proposed methodology on a blind well and comparedthe results with those of the simultaneous inversion, indicatingcomparable levels of accuracy. Therefore, application of thismethod in seismic geomechanics can bring about significantprogress in the future.

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