Aeolian Landform (08. Erg)

08. Erg                                                                                                                                                   Back to Aeolian Landforms

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

• 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 Africa, central 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