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loess

loess is a sedimentary rock, transported by wind, having special yellowish color and extremely high minerals" target="_blank">clay minerals content. Due to these it is a very good soil forming basic rock.
It is an aeolian sediment formed by the accumulation of wind-blown silt and lesser and variable amounts of fine sand and clay. loess is homogeneous, porous, friable, pale yellow, slightly coherent, typically non-stratified and often calcareous. The expression „loess” comes from the German Löss or Löß, and ultimately from Swiss German lösch meaning loose as named by peasants and masons along the Rhine Valley.loess grains are angular with little polishing or rounding and composed of crystals of quartz, feldspar, mica and other minerals. loess tends to develop into highly rich soils. Under appropriate climatic conditions it is some of the most agriculturally productive terrain in the world. In the lower portions of a loess deposit the calcium carbonate tends to form concretions, which on account of their mimetic forms have received such names as, "loess dolls”.The loess can be of glacial and non-glacial origin. Glacial loess is derived from the floodplains of glacial braided rivers that carried large volumes of glacial meltwater and sediments from the annual melting of continental icesheets and mountain icecaps during the summer. Non-glacial loess can originate from deserts, dune fields, playa lakes and volcanic ash. Hungary has several areas that are covered by loess of glacial origin. At locations such as Dunaújváros and Balatonkarattya, loess walls are exposed as loess reefs. Vertical stability of loess is extremely high.