Mechanics of deposition of sand (and dust formation in sand storms)

Mechanics of deposition of Sand has been studied using a stereomicroscope, and slow motion film technique. A single Sand particle, after striking deposition surface,rebounds in random direction - spinning with high speed which has been quantified for Certain heights of fall (of the particle). The events taking place on the surface of deposition are also studied. The study is extended to mechanics of deposition of group of sand particles, deposited by Controlled process of vertical deposition. The analysis of the results bring out some of the causes of formation of Macropores which form an inherent property of packings of granular soils.The study suggests mechanics of formation of dust in Sand Storms.