“…Therefore, the best available choice for rock physics modeling of shales in this study is using a laminar/layered model performed through the Backus averaging. Shale layers within the sand matrix often show horizontally aligned orientation, thus making a transversely isotropic (TI) medium with a vertical axis of symmetry also known as VTI medium characterized either in terms of five independent elastic/stiffness constants (C 11 , C 13 , C 33 , C 55 , and C 66 ) or of two vertical velocities (V P and V S ) and three Thomsen anisotropic parameters (Ȗ, į, İ) (Thomsen 1986, Tsvankin 1997aAli et al 2011).…”