Erg (landform)

For other uses, see Erg (disambiguation).
Issaouane Erg, Algeria
Linear Dunes, Namib Sand Sea

An erg (also sand sea or dune sea, or sand sheet if it lacks dunes) is a broad, flat area of desert covered with wind-swept sand with little or no vegetative cover.[1] The word is derived from the Arabic word ʿirq (عرق), meaning "dune field".[2] Strictly speaking, an erg is defined as a desert area that contains more than 125 km2 (48 sq mi) of aeolian or wind-blown sand[3] and where sand covers more than 20% of the surface.[2] Smaller areas are known as "dune fields".[4] The largest hot desert in the world, the Sahara, covers 9 million square kilometres (3.5×10^6 sq mi) and contains several ergs, such as the Chech Erg and the Issaouane Erg in Algeria.[5] Approximately 85% of all the Earth's mobile sand is found in ergs that are greater than 32,000 km2 (12,355 sq mi),[6] the largest being the Rub' al Khali, the Empty Quarter of the Arabian Peninsula. Ergs are also found on other celestial bodies, such as Venus, Mars, and Saturn's moon Titan.

  1. ^ "Issaouane Erg, Algeria". NASA Earth Observatory. Archived from the original on 2006-10-01. Retrieved 2006-05-18.
  2. ^ a b "Summary: Sand Seas/Ergs/Dune Fields". Desert Guide. United States Army Corps of Engineers. Retrieved 2006-05-18.[permanent dead link]
  3. ^ Parrish, Judith Totman (2001). Interpreting Pre-Quaternary Climate from the Geologic Record. Columbia University Press. p. 166. ISBN 978-0-231-10207-0.
  4. ^ Landforms in the World: Aeolian Landform (08. Erg)
  5. ^ Spector, Christy (September 24, 2001). "Soil Forming Factors". NASA Goddard Space Flight Center. Archived from the original on 2006-08-28. Retrieved 2006-05-18.
  6. ^ Cooke, Ronald U.; Warren, Andrew (1973). Geomorphology in deserts. University of California Press. p. 322. ISBN 978-0-520-02280-5.