The fine dust blown beyond the desert limits is deposited on neighbouring lands as loess. It is a yellow, friable material and is usually very fertile. Loess is in fact, fine loam, rich in lime, very coherent and extremely porous. Water sinks in readily so that the surface is always dry. Streams have cut deep valleys through the thick mantle of soft loess and badland topography may develop. It is so soft that roads constructed through a loess region soon sink and their walls rise steeply.
The most extensive deposit of loess is found in north-west China in the loess plateau of the Hwang- Ho basin. It is estimated to cover an area of 250,000 square miles, and the deposits have accumulated to a depth of 200 to 500 feet! In China, such yellowish wind-borne dust from the Gobi Desert is called 'Hwangtu' - the yellow earth! But the original term loess actually comes from a village in Alsace, France bearing that name, where such deposits occurred. Similar deposits also occur in some parts of Germany, France and Belgium, and are locally called limon.
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The most extensive deposit of loess is found in north-west China in the loess plateau of the Hwang- Ho basin. It is estimated to cover an area of 250,000 square miles, and the deposits have accumulated to a depth of 200 to 500 feet! In China, such yellowish wind-borne dust from the Gobi Desert is called 'Hwangtu' - the yellow earth! But the original term loess actually comes from a village in Alsace, France bearing that name, where such deposits occurred. Similar deposits also occur in some parts of Germany, France and Belgium, and are locally called limon.
For more updates stay tuned.
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