Editing Loess (section)

==Properties==
[[File:Loess landscape china.jpg|thumb|Loess near [[Hunyuan]], [[Datong]], [[Shanxi]], China]]
[[File:Löss 1.jpg|thumb|Loess from the [[Rhine]] lowlands near [[Mannheim]] with calcareous concretions]]
Loesses are [[wikt:homogeneous|homogeneous]], [[Porosity#Porosity in earth sciences and construction|porous]], [[friable]], pale yellow or [[buff (color)|buff]], slightly [[wikt:coherent|coherent]], typically non-[[stratum|stratified]], and often [[calcareous]]. Loess grains are [[Rounding (sediment)|angular]], with little polishing or rounding, and composed of [[quartz]], [[feldspar]], [[mica]], or other [[mineral]] crystals. Loesses have been described as rich, dust-like soil.<ref>Pearson Prentice Hall - World Studies - Europe and Russia</ref>

Loess deposits may become very thick: at more than a hundred meters in areas of Northwestern China and tens of meters in parts of the [[Midwestern United States|Midwestern]] United States. Loesses generally occur as blanket deposits that cover hundreds of square kilometers. The deposits are often tens of meters thick. Loesses often have steep or vertical faces.<ref>Neuendorf, K.E.K., J.P. Mehl Jr., and J.A. Jackson, 2005, ''Glossary of Geology.'' [[Springer-Verlag]], [[New York City]], 779 pp., {{ISBN|3-540-27951-2}}</ref> Because the grains are angular, loesses will often stand in banks for many years without [[Slump (geology)|slump]]ing. This type of soil has "vertical cleavage", and thus, it can be easily excavated to form cave dwellings, which is a popular method of making [[yaodong|human habitations]] in some parts of China. However, loesses can readily erode.

In several areas of the world, loess [[ridge]]s have formed that had been aligned with the [[prevailing wind]]s during the last [[glacial maximum]]. These are called "[[paha (landform)|paha]] ridges" in America and "greda ridges" in Europe. The formation of these loess [[dune]]s has been explained as a combination of wind and [[tundra]] conditions.