The Interpretation of Flow-markings and Load-casts

Abstract

Some sedimentary structures commonly found at the base of beds of greywacke have been given a variety of names. It is suggested that the name flute-cast be used for scour-and-fill structures, which are shown to be oriented parallel to the direction of sediment movement. Superficially similar structures, described as flow-casts, are formed by movement of the greywacke during and after its deposition; study of their internal structure and their relations to ripple-direction shows them to be oriented at right angles to the current direction.