Monoclinic and triclinic 3D flanking structures around elliptical cracks

► In this study, 3D flanking structures are modelled which develop around an elliptical crack sheared in a defined background flow. ► The structures are dependent on the aspect ratio of the crack, and can thus not be sufficiently modelled by a 2D approach. ► Cracks oriented oblique to the shearing or stretching direction of a shear zone produce triclinic structures, which form in monoclinic shear zones and may be used to determine kinematics and finite strain.