Abstract
THE stratification of wind-accumulated sand beds is well-known, and the evidence of it can often be seen on the vertical faces of sand-pits. Beadnell1 has shown that the laminar structure of fresh non-cohesive dune sand can also be observed, if the dry dune is soaked with water to allow a vertical face to be exposed without collapse. The strata he thus exposed dipped at the angle of repose of sand, which experiments show to lie between 30½° and 35¾° to the horizontal2. In this case the succeeding layers have been formed by sand which, having been driven over the surface of the dune, has come to rest temporarily sheltered on the upper part of the slope, and has accumulated there, increasing the angle of the slope until shear occurs. An avalanche then takes place down the slope from top to bottom (Fig. 1). Fresh sand deposits formed in this way are characterized by their loose packing and by their extreme softness. I have called3 such a mode of deposition 'encroachment'.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
