56
LONGITUDINAL
SEIF DUNES
WIND REVERSAl
PRODUCES CLiMBING
RIPPLES, OR PARTIAL REWOAKING
OF SLOPE AND RIPPLES ON QUNE CREST
c
a
b
Chapter 2 Continental Sediments
PREVAILING WIND
DIRECTION
~ PARABOLIC DUNES
LUNETTE
RELATIVE VELOCITIES OF SAND MOVEMENT
ON FlAT SURFACE AND MIGRATION OF BARCHANS
UNDERCUTTING OF
LEE-SIDE SLOPE
GRAIN FALL LAMINAT ION
d
EROSION OF
PROGRADING
MAJOR PART
NEW DUNE
OF OLDER DUNE
\ ;;.;::-._------F'-_.~-\- ~~~~,~?:. . . '''~.: . .::;?"! /~" I
~~~ " ;....- - ' ~
OLDER
TAUN CATION
SURFACE