Aeolian Landform (12. Yardang)

12. Yardang                                                                                                                                           Back to Aeolian landforms

• Low ridges carved in soft rock by wind in flat desert.

• A yardang is a streamlined hill carved from ,bedrock ,consolidated ,semiconsolidated material.

• Action of creating yardang ;

                -wind abrasion
                -dust

Tsaidam Desert, Qinghai Province, China.

                -sand
               -deflation

• Most yardang fields are in sand-poor areas.

• These are longer than wide. 

• Yardangs are formed by wind erosion &  cohesive material.

• They are more commonly created from softer rock types like;

                 -siltstone
                 -sandstone
                 -shale
                 -limestone

• Yardang mostly have flat surface of harder and softer material.

•  The soft material is eroded and removed by the wind, and the harder material remains.

• There are 3 types of yardangs; 

                 1.mega-yardangs =100m high

                                                   Several km long

                                                   Can fing arid regions with strong wings

                                                    examples: *Tibesti Mountains in the central Sahara.

                                                                    *"Hole in the Rock" in Papago Park in Phoenix, Arizona

                                                                    * Window Rock, Arizona.

                                                                    *Riverbed of the Kurruk-daria in Central Asia.

                 2.meso-yardangs=Few meters high

                                                 10 to 15 meters long 

                                                Found carved in semiconsolidated playa, sediments & other soft granular materials.

                 3.micro-yardangs=Few centimeters high.

• Other common names

             -Mud-lions
             -Sphinxlike hills
             -Mushroom rocks
             -Iinselbergs
             -Koukour (common in Tunisia)
             -Kalut (Iran)
            -Cretes et couloirs (Chad).

A yardang near Meadow, Texas