Rotliegend

The Rotliegend, Rotliegend Group or Rotliegendes (German: the underlying red) is a lithostratigraphic unit (a sequence of rock strata) of latest Carboniferous to Guadalupian (middle Permian) age that is found in the subsurface of large areas in western and central Europe. The Rotliegend mainly consists of sandstone layers. It is usually covered by the Zechstein and lies on top of regionally different formations of late Carboniferous age.

The name Rotliegend has in the past not only been used to address the rock strata themselves, but also the time span in which they were formed (in which case the Rotliegend was considered a series or subsystem of the Permian). This time span corresponds roughly with the length of the Cisuralian epoch.

In large parts of Pangaea, the last phases of the Hercynian orogeny were still ongoing during the start of the Permian. At the same time local crustal extension formed intramontane basins such as the large Permian Basin which covered parts of present-day Germany, Poland, Denmark, the North Sea, the Baltic Sea and the Netherlands. The early development of the basin went hand in hand with volcanism. Apart from these volcanic deposits the basin was filled by the erosional products of the Hercynian mountains to the south: mostly sands and gravels deposited under an arid and warm climate.

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