Abstract

Grain-size analysis by settling techniques presupposes free sinking of particles. Settling convection is a current system set up by different densities of clouds in a settling suspension. Settling convection tends to augment the sinking velocity of sand grains released at the surface, especially in samples with a narrow range in size and also for particles of less than 0.1-0.05 mm. Hence, the usefulness of various types of sedimentation analyzers based on sample introduction from above is restricted to sizes above 50 microns. Settling convection also renders ineffective counter-current methods (elutriators) in water. Elutriation in air is inapplicable for lutum particles that have been wet, hence for most natural sediments except eolian deposits.

You do not currently have access to this article.