A revised conceptual model for calcareous shales: Insights from mean-field homogenisation

Predicting the macroscopic elastic response of shale from the scale of its building blocks has become an active area of research in recent years. Mean-field homogenisation-based modelling to predict the macroscopic elastic constants of shale has become popular owing to its relative simplicity. Yet, for this approach to be successful, an appropriate conceptual model is needed in order to inform the design of the multiscale homogenisation approach. This paper investigates the consequences of applying the prevailing conceptual paradigm to anisotropic calcareous shales. Recently obtained experimental micro and nanomechanics data for calcareous shales will be used to show how best we can adapt the mean-field homogenisation approach to model this class of fine grained sediment.