This soil has a characteristic called vertical cleavage which makes it easily excavated to form cave dwellings, a popular method of making human habitations in some parts of China. In several areas of the world, loess ridges have formed that are aligned with the prevailing winds during the last glacial maximum.These are called "paha ridges" in America and "greda ridges" in Europe.Relative to the pampean loess the neotropical loess is poor in quartz and calcium carbonate.The source region for this loess is thought by some scientists to be areas of fluvio-glacial depostis the Andean foothills formed by the Patagonian Ice Sheet.The loess deposits found along both sides of the Mississippi River Alluvial Valley are a classic example of periglacial loess.During the Quaternary, loess and loess-like sediments were formed in periglacial environments on mid-continental shield areas in Europe and Siberia, on the margins of high mountain ranges like in Tajikistan and on semi-arid margins of some lowland deserts like in China.Loess grains are angular with little polishing or rounding and composed of crystals of quartz, feldspar, mica and other minerals. Loess deposits may become very thick; more than a hundred meters in areas of China and tens of meters in parts of the Midwestern United States.
the time elapsed since the last exposure of the mineral grains to daylight.
Loess often stands in either steep or vertical faces.
Because the grains are angular, loess will often stand in banks for many years without slumping.
The form of these loess dunes has been explained by a combination of wind and tundra conditions.
Loess comes from the German Löss or Löß, and ultimately from Alemannic lösch meaning loose as named by peasants and masons along the Rhine Valley.