Recognition of channel floors in ancient fluvial conglomerates

Abstract

Fabric and structure in clast-supported fluvial conglomerates of the Oligocene Noda Group display channel floors of rather high-sinuosity. A key structure of such channel deposits is a symmetrical or asymmetrical concave-up gravel alignment. Dip angle of some gravels is very high. Such high-angle dip direction was probably the product of resultant force of the gravity pull and the traction current that imbricates the gravels to the upstream dip.