Abstract
Since shales are the far most abundant overburden formation, understanding the geomechanical and rock physics behavior of shales is essential. We discuss a particular deep overburden shale in light of a thorough static and dynamic multi-directional data acquisition, as a basis for complete static and dynamic characterization assuming transverse isotropy. The stress-and strain-path dependence of the principal P- and S-wave velocities are also analyzed. These quantities are of great interest for interpretation of seismic or sonic-log overburden signatures upon reservoir depletion (or injection), as geomechanical simulations show significant variations of stress and strain changes throughout the overburden. The knowledge of angular dependence of velocities is also of fundamental importance in the petroleum industry for correct inversion and interpretation.