Aeolian Landform (08. Erg)

08. Erg                                                                                                                                                   Back to Aeolian Landforms


    Rub' al Khali Arabi
    Rub' al Khali Arabi
  • An erg called as;
                 -Sand sea
                 -Dune sea
                 -Sand sheet 
  • Erg's are broad, flat area of desert covered with wind-swept sand with little or no vegetative cover.
  • The term takes its name from the Arabic word, meaning "dune field". 
  • An erg is defined as a desert area that contains more than 125 square kilo metres of aeolian or wind-blown sand and where sand covers more than 20% of the surface. 
  • Smaller areas are known as "dune fields". The largest hot desert in the world, the Sahara, covers 9 million square kilometres (3.5×106 sq mi) and contains several ergs.
    Morocco_Africa
    Morocco Africa
  • Sand seas and dune fields generally occur in regions downwind of copious sources of dry, loose sand, such as;
                     -dry riverbeds
                     -deltas
                     -floodplains
                     -glacial outwash plains
                     -dry lakes
                     -beaches. 
  • All major ergs are located downwind from river beds.
  • Individual dunes in ergs typically have widths, lengths, or both dimensions greater than 500 m.
  • The depth ergs  is selima Sand Sheet of Southern Egypt,Simpson Desert in the Sahara
  • Mesozoic and Paleozoic ergs reached a mean depth of more than 100m..
  •  The only active erg in North America is in the Gran Desierto de Altar

  • The largest are in northernand southern Africacentral and western Asia, and Central Australia.
  •  In South America, ergs are limited by the Andes Mountains.
some examples-:  -Coastal Peru
                               - Northwestern Argentina
                                -Northeast coast of Brazil.





Issaouane Erg Algeria
Issaouane Erg Algeria

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