Experiments on the Rate of Wear of Sand Grains

Abstract

The experiments described in this paper were made to obtain more definite data on the relative rates of mechanical wear, on sand grains, by wind and water under constant conditions. The results show, contrary to the general belief, that sand submerged in water wears down more rapidly than dry sand transported over the same distance. From the experiments, the ratio of the rate of wear of water-transported to wind-transported sand ranges from 1.7:1 to 4.6:1. Also, the rate of wear by both wind and water, in a well-sized sand such as a dune or beach sand, is found to be very slow. Rounded or spheroidal sand grains are believed to have a longer history of rounding than could be produced in a single cycle of erosion, transportation, and deposition and probably are, even geologically, very old.