The Buntsandstein (German for ''coloured'' or ''colourful sandstone'') or Bunter sandstone is a lithostratigraphic and allostratigraphic unit (a sequence of

rock strata In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as e ...

) in the

subsurface In geology, bedrock is solid rock that lies under loose material (regolith) within the crust of Earth or another terrestrial planet. Definition Bedrock is the solid rock that underlies looser surface material. An exposed portion of bedr ...

of large parts of west and central Europe. The Buntsandstein predominantly consists of

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicat ...

layers of the

Lower Triassic The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a ...

series and is one of three characteristic Triassic units, together with the

Muschelkalk The Muschelkalk (German for "shell-bearing limestone"; french: calcaire coquillier) is a sequence of sedimentary rock strata (a lithostratigraphic unit) in the geology of central and western Europe. It has a Middle Triassic (240 to 230 million ...

and

Keuper The Keuper is a lithostratigraphic unit (a sequence of rock strata) in the subsurface of large parts of west and central Europe. The Keuper consists of dolomite, shales or claystones and evaporites that were deposited during the Middle and Lat ...

that form the Germanic Trias Supergroup. The Buntsandstein is similar in age,

facies In geology, a facies ( , ; same pronunciation and spelling in the plural) is a body of rock with specified characteristics, which can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formatio ...

and

lithology The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Li ...

with the Bunter of the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isl ...

. It is normally lying on top of the

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleo ...

Zechstein and below the Muschelkalk. In the past the name Buntsandstein was in Europe also used in a

chronostratigraphic Chronostratigraphy is the branch of stratigraphy that studies the ages of rock strata in relation to time. The ultimate aim of chronostratigraphy is to arrange the sequence of deposition and the time of deposition of all rocks within a geologi ...

sense, as a subdivision of the Triassic system. Among reasons to abandon this use was the discovery that its base lies actually in the latest Permian.

Origin

The Buntsandstein was deposited in the

Germanic Basin The Germanic Basin (german: Germanisches Becken) is a large region of sedimentation in Western and Central Europe that, during the Permian and Triassic periods, extended from England in the west to the eastern border of Poland in the east. To the ...

, a large

sedimentary basin Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock. They form when long-term subsiden ...

that was the successor of the smaller Permian Basin and spread across present day

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

, Germany,

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

, the southern regions of the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...

and

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden and the North and Central European Plain. The sea stretches from 53°N to 66°N latitude and from ...

, the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

and south England. In the late Permian this region had an

arid climate The desert climate or arid climate (in the Köppen climate classification ''BWh'' and ''BWk''), is a dry climate sub-type in which there is a severe excess of evaporation over precipitation. The typically bald, rocky, or sandy surfaces in deser ...

and it was covered by inland seas which deposited the Zechstein

evaporite An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocean ...

s. At the end of the Permian a connection with the Paleo-Tethys Ocean to the south was formed in present-day southeast Poland, causing sea water to flow in periodically. This caused the inflow of more

clastic Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks ...

material, which was deposited in the form of large

alluvial fan An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to semiarid climates, but a ...

s. Deposition took place in an arid,

continent A continent is any of several large landmasses. Generally identified by convention rather than any strict criteria, up to seven geographical regions are commonly regarded as continents. Ordered from largest in area to smallest, these seven ...

al environment ( playa facies), so that there was little chemical weathering. Therefore, the Buntsandstein deposits are typical

red beds Red beds (or redbeds) are sedimentary rocks, typically consisting of sandstone, siltstone, and shale, that are predominantly red in color due to the presence of ferric oxides. Frequently, these red-colored sedimentary strata locally contain t ...

, mainly sandstones and conglomerates with little

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay pa ...

. The late

Anisian In the geologic timescale, the Anisian is the lower stage or earliest age of the Middle Triassic series or epoch and lasted from million years ago until million years ago. The Anisian Age succeeds the Olenekian Age (part of the Lower Triassic ...

saw a major rise of the global ( eustatic) sea level. A tropical sea filled the Germanic Basin then, stopping the deposition of the Buntsandstein and marking the beginning of the deposition of the Muschelkalk.

Stratigraphy

The Buntsandstein belongs to the

Changhsingian In the geologic time scale, the Changhsingian or Changxingian is the latest age or uppermost stage of the Permian. It is also the upper or latest of two subdivisions of the Lopingian Epoch or Series. The Changhsingian lasted from to 251.902 ...

to Anisian stages, meaning it is between 252 and 246 million years old.Manfred Menning, Reinhard Gast, Hans Hagdorn, Karl-Christian Käding, Theo Simon, Michael Szurlies und Edgar Nitsch: Zeitskala für Perm und Trias in der Stratigraphischen Tabelle von Deutschland 2002, zyklostratigraphische Kalibrierung der höheren Dyas und Germanischen Trias und das Alter der Stufen Roadium bis Rhaetium 2005. Newsletters on Stratigraphy, 41(1–3): 173–210, Stuttgart 2005 ISSN 0078-0421 In German lithostratigraphy, it is seen as a group, in the Netherlands and North Sea the name has no official status (though that does not keep geologists from using it). In the official Dutch lithostratigraphy, the Buntsandstein is divided into the Lower and

Upper Germanic Trias Group Upper may refer to: * Shoe upper or ''vamp'', the part of a shoe on the top of the foot * Stimulant, drugs which induce temporary improvements in either mental or physical function or both * ''Upper'', the original film title for the 2013 found f ...

s. The British Bunter Formation is basically a continuation of the same unit. In Germany the Buntsandstein is subdivided into three subgroups with seven formations (from top to base): Upper Buntsandstein *

Röt Formation The Röt Formation or Rötton Formation (German for Röt Shale), or Upper Buntsandstein, is a geologic formation of the Buntsandstein in Germany. It preserves fossils dating back to the Middle Triassic Epoch (Anisian or Aegean or Bithynian in th ...

or Fährtensandstein Middle Buntsandstein * Solling Formation * Hardegsen Formation * Detfurth Formation * Volpriehausen Formation Lower Buntsandstein * Bernburg Formation * Calvörde Formation All of these are reasonably good reservoir rocks for oil and gas. In the Dutch subdivision, the upper two formations are part of the Upper Germanic Trias and the others part of the Lower Germanic Trias.

Natural monuments

Bunter sandstone often forms spectacular rock formations as a result of weathering: including isolated rocks several tens of metres high. Most of them are designated

natural monument A natural monument is a natural or natural/cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities or cultural significance. Under World Commission on Protected Areas guidelines, na ...

s, for example, the Devil's Table near Hinterweidenthal. In the Palatinate, near

Eppenbrunn Eppenbrunn is a municipality in Südwestpfalz district, in Rhineland-Palatinate, western Germany and belongs to the municipal association Pirmasens-Land. Within the municipality is the 1.5 km long bunter sandstone The Buntsandstein (Germ ...

, are the so-called ''

Altschlossfelsen The ''Altschlossfelsen'' (, "Old Castle Rocks") is a rock outcrop formed of bunter sandstone in the Palatine Forest of Germany, near the border with France. The 1,500-metre-long rock wall is located on a hill known as the ''Brechenberg'' near E ...

'' ("Old Castle Rocks"). The massif has a length of around 1.5 km and a height of up to 25 metres, easily the largest bunter sandstone massif in the Palatinate. On the island of

Heligoland Heligoland (; german: Helgoland, ; Heligolandic Frisian: , , Mooring Frisian: , da, Helgoland) is a small archipelago in the North Sea. A part of the German state of Schleswig-Holstein since 1890, the islands were historically possession ...

, the 47-metre-high '' Lange Anna'' ("Tall Anna"), is the best-known landmark on the island and was declared a natural monument in 1969.

Fossils

The Buntsandstein contains a few small saurians, tracks like Chirotherium and plant remnants.

Notes

References

* *

External links

*(In Dutch
Structural description of the Dutch Triassic, including stratigraphic diagrams
website of TNO. {{Authority control Triassic System of Europe Lithostratigraphy Geology of Germany Lithostratigraphy of Germany Stratigraphy of Europe