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Analysis of Eshelby-Cheng's Model in Anisotropic Porous Cracked Medium: an Physical Modeling Approach
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 81st EAGE Conference and Exhibition 2019, Jun 2019, Volume 2019, p.1 - 5
Abstract
In this work we perform an analysis of the Eshelby-Cheng model when applied to anisotropic with VTI backgrounds, testing the model for the elastic velocities as functions of aspect ratio against experimental data. The data set were obtained from 17 synthetic samples, one uncracked and 16 cracked. In these samples, ultrasonic measurements were performed in order to obtain the experimental velocities used to test the model. As was not possible to acquire data for velocity as function of aspect ratio for fixed values of crack density, we performed interpolations of the experimental data to estimate these velocities. Eshelby-Cheng model effective velocities were calculated using two formulations proposed for the crack porosity: one proposed by Thomsen and the other proposed in this work. The comparisons between elastic velocities - as function of crack aspect ratio, predicted by the model and estimated from the data via interpolation showed that the fitting depends on the formulation choosen and on the crack aspect ratio range analyzed. For low aspect ratio cracks (lower than 0.3) the Eshelby-Cheng model with the porosity proposed by Thomsen fits better the data, while for high aspect ratio cracks (higher than 0.3), our formulation produces a better fitting.