Abstract
Shales are anisotropic, but their anisotropy is often neglected in geomechanical field applications. A major reason for this omission is the need for input data, which includes at least five different elastic parameters that are not commonly available. Recent developments have pointed to internal correlations between elastic anisotropy parameters that can be linked to textural and compositional similarities between different shales. Oriented clay minerals constitute the main source of lithological anisotropy. Utilizing the internal correlations in a pragmatic and simple manner, we demonstrate that a reasonably good anisotropic characterization can be given, even if only one or two input parameters are available. Such a default anisotropic formulation is likely to yield more accurate results for several engineering applications rather than simply assuming isotropy. Several improvements are available, and some already exist, but at the cost of requiring more input from logs or core measurements. Further refinement of our current approach is a low-hanging fruit.