Sedimentation. Stratification and Bedding a Stratification or bedding, is the arrangement of sedimentary particles in layers. Each stratum(plural= strata or bed is a distinct later of sediment The top or bottom surface of a bed is a bedding plane.Sedimentation, Stratification, and Bedding ◼ Stratification or bedding, is the arrangement of sedimentary particles in layers. ◼ Each stratum (plural = strata) or bed is a distinct later of sediment. ◼ The top or bottom surface of a bed is a bedding plane