FORMATION OF “DUNES” ON RIVER-BED

Abstract

This paper is a report of the observation on the condition of river meandering from the standpoint of “DUNE” formation.The following characteristics of the “DUNE” are explained inductively from examples of thirty different rivers in eastern Japan with added comparisons to experimental results, and the characteristics are: that “DUNES”, having a form like sand dunes, are formed on the river-bed during the flood; that the formation is made whether the river is rapid or slow and the river-bed is sand or gravel; that remarkable developments are observed in areas of the river where there is a tendency towards aggradation; the influence upon the form at low water; the relationship with the river meandering; transformation by the flood.