Are 'Bedding Plane' and 'Pre-sheared Plane' in a clay domain same? Are 'Bedding Plane' and 'Pre-sheared Plane' in a clay domain same? kushtian (Geotechnical) (OP) 7 Jan 16 17:46 'Bedding Plane' = 'Pre-sheared Plane' [????] Any enlightment? TIA RE: Are 'Bedding Plane' and 'Pre-sheared Plane' in a clay domain same? emmgjld (Geotechnical) 7 Jan 16 19:14 Not by definition, assuming I am understanding what you are implying with Pre-sheared Plane. However, both features may occupy the same position/place within a deposit. A bedding plane is a result of geologic depositional processes. A Pre-sheared Plane, as I understand it, indicates movement after deposition, such as an older landslide, solifluction, faulting, etc. Now please note that geologic depositional processes involve continuous shearing as the material is initially being placed, with the deposit entering a 'stabilized state' after mass movement has ceased the the deposit entering the process of hardening or in the extreme case, lithification.