- 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 ;
-dust
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| Tsaidam Desert, Qinghai Province, China. |
-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;
-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;
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
-Sphinxlike hills
-Mushroom rocks
-Iinselbergs
-Koukour (common in Tunisia)
-Kalut (Iran)
-Cretes et couloirs (Chad).
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| A yardang near Meadow, Texas |
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