Version 0.0.1 release
This release contains the first modules released for AnisotroPy - effective_modelling and materials. These modules operate in combination to produce simple models of the effective anisotropy/splitting induced by media with numerous elastic layers and inclusions. Based on a number of works, the results have been validating (where possible) against the outputs of the MATLAB routines provided by MSAT (MATLAB Seismic Anisotropy Toolkit). The purpose here is not to replace these existing routines, but simply provide an open-source Python implementation for the MATLAB-averse/those who do not have a license.
Effective modelling
This module brings together a number of models for calculating the effective elastic anisotropy of different media.
- Hudson - modelling the effective elastic anisotropy of a rock hosting penny-shaped cracks, based on the series of works by J. Hudson.
- N-layers - modelling the effective shear-wave splitting induced by N sequential layers of anisotropy, based on the analytical equations presented in Silver and Savage (1994), which are appropriate for weak anisotropy.
- Backus - modelling the effective elastic anisotropy of a medium composed of alternating layers of isotropic material, based on the analytical equations presented in Backus (1962).
- Tandon & Weng - modelling the effective elastic anisotropy of a rock hosting spheroidal inclusions, based on the analytical equations presented in Tandon and Weng (1984).
Materials
This module provides a simple representation of an arbitrarily (an)isotropic elastic material, and a (currently small!) database of published stiffness/compliance moduli/densities. Feel free to add any materials! Routines for "mixing" these base materials to form a composite and calculating the effective elastic moduli are provided (based on the Reuss, Voigt, and Reuss-Voigt-Hill averages).