As each new layer of sand falls down the slip face of the dune, cross beds are formed.in cross beds each layer is formed at an angle to the ground.wt he mean

Cross beds are sedimentary structures form as a result of ripple propagation. Sediments are carried along the stream and due to reduced flow velocity in Lee side, they got deposite...

As the dune prograces the stoss side gets eroded and the Lee side is preserved .after one wind current another wind after another wind and so on so the stoss side will be eroded b...