Effective medium model in shales and sandstones at multifrequency observations

This rock-physics investigation aims to understand the elastic response of shales and poorly-consolidated sands with special attention to the variations in textural expression including mineralogy, preferred clay alignment, and porosity; as well as non-textural parameters: stress state and fluid saturation. This research explores such elastic response to produce a deeper understanding in the frequency-related behavior through a modeling approach. Within this framework, two specific aspects are investigated: (i) the elastic modulus as a function of pressure variation, as well as silt- and fluid- inclusion in an anisotropic clay medium, that will consequently produce different clay preferred alignment and distinct anisotropic behaviour at different frequency regime; (ii) the elastic modulus as function of porosity and water-saturation in isotropic granular media, that also addresses frequency-velocity dispersion by acknowledging the microscopic component.