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arXiv · 1804.06891

On the Backus average of layers with randomly oriented elasticity tensors

Len Bos·Michael A. Slawinski·Theodore Stanoev
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Abstract

As shown by Backus (1962), the average of a stack of isotropic layers results in a transversely isotropic medium. Herein, we consider a stack of layers consisting of a randomly oriented anisotropic elasticity tensor, which-one might expect-would result in an isotropic medium. However, we show-by means of a fundamental symmetry of the Backus average-that the corresponding Backus average is only transversely isotropic and not, in general, isotropic. In the process, we formulate, and use, a relationship between the Backus and Gazis et al. (1963) averages.

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Len Bos, Michael A. Slawinski, Theodore Stanoev. 2018-04-18. On the Backus average of layers with randomly oriented elasticity tensors. https://arxiv.org/abs/1804.06891

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