1. Deserts
Very well sorted sand accumulates in giant fields, called Ergs, up to 500,000 km3 in extent within continental depressions. Usually <200 m thick. Ergs comprise giant km-scale Draa, which in turn are built of smaller dunes, whose form vary with grain size and wind strength. Modern example: Algerian and Saudi Ergs. Ancient example: Permian New Red Sandstone, Jurassic Navajo Sandstone of Utah.

2. Dune morphology

3. Grain size- dune wavelength

4. Erg morphology

5. Paleo-currents-dune types

6. Crescent dunes- Arabia

7. Linear seif dunes, Yemen

8. Linear seif dune field, Lut, Iran

9. Star shaped dune, Namibia

10. Cross-bedded dune sandstones

11. Bioturbation in aeolian sand

12. Barchan dune field, Nubra, India