The Saxothuringian Zone or Saxothuringicum is in geology

Geology

Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...

 a structural

Structural geology

Structural geology is the study of the three-dimensional distribution of rock units with respect to their deformational histories. The primary goal of structural geology is to use measurements of present-day rock geometries to uncover information about the history of deformation in the rocks, and...

 or tectonic

Tectonics

Tectonics is a field of study within geology concerned generally with the structures within the lithosphere of the Earth and particularly with the forces and movements that have operated in a region to create these structures.Tectonics is concerned with the orogenies and tectonic development of...

 zone in the Hercynian or Variscan orogen (380-270 million years old) of central and western Europe. Because rocks of Hercynian age are in most places covered by younger strata, the zone is not everywhere visible at the surface. Places where it crops out

Outcrop

An outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. -Features:Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by a mantle of soil and vegetation and cannot be...

 are the northern Bohemian Massif

Bohemian Massif

The Bohemian Massif; or Český masiv; is in the geology of Central Europe a large massif stretching over central Czech republic, eastern Germany, southern Poland and northern Austria...

, the Spessart

Spessart

The Spessart is a low mountain range in northwestern Bavaria and southern Hesse, Germany. It is bordered on three sides by the Main River. The two most important towns located at the foot of the Spessart are Aschaffenburg and Würzburg....

, the Odenwald

Odenwald

The Odenwald is a low mountain range in Hesse, Bavaria and Baden-Württemberg in Germany.- Location :The Odenwald lies between the Upper Rhine Rift Valley with the Bergstraße and the Hessisches Ried in the west, the Main and the Bauland in the east, the Hanau-Seligenstadt Basin – a subbasin of...

, the northern parts of the Black Forest

Black Forest

The Black Forest is a wooded mountain range in Baden-Württemberg, southwestern Germany. It is bordered by the Rhine valley to the west and south. The highest peak is the Feldberg with an elevation of 1,493 metres ....

 and Vosges

Vosges

Vosges is a French department, named after the local mountain range. It contains the hometown of Joan of Arc, Domrémy.-History:The Vosges department is one of the original 83 departments of France, created on February 9, 1790 during the French Revolution. It was made of territories that had been...

 and the southern part of the Taunus

Taunus

The Taunus is a low mountain range in Hesse, Germany that composes part of the Rhenish Slate Mountains. It is bounded by the river valleys of Rhine, Main and Lahn. On the opposite side of the Rhine, the mountains are continued by the Hunsrück...

. West of the Vosges terrane

Terrane

A terrane in geology is short-hand term for a tectonostratigraphic terrane, which is a fragment of crustal material formed on, or broken off from, one tectonic plate and accreted or "sutured" to crust lying on another plate...

s on both sides of the English Channel

English Channel

The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...

 are also seen as part of the zone, for example the Lizard complex in Cornwall

Cornwall

Cornwall is a unitary authority and ceremonial county of England, within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of , and covers an area of...

 or the Léon Zone of the Armorican Massif

Armorican Massif

The Armorican Massif is a geologic massif that covers a large area in the northwest of France, including Brittany, the western part of Normandy and the Pays de la Loire. Its name comes from the old Armorica, a Gaul area between the Loire and the Seine rivers...

 (Brittany

Brittany

Brittany is a cultural and administrative region in the north-west of France. Previously a kingdom and then a duchy, Brittany was united to the Kingdom of France in 1532 as a province. Brittany has also been referred to as Less, Lesser or Little Britain...

).

Location

In central Europe the Saxothuringian Zone is situated between the Rhenohercynian Zone

Rhenohercynian Zone

The Rhenohercynian Zone is in structural geology a fold belt of west and central Europe, formed during the Hercynian orogeny . The zone consists of folded and thrusted Devonian and early Carboniferous sedimentary rocks that were deposited in a back-arc basin along the southern margin of the then...

 to the northwest and the Moldanubian Zone

Moldanubian Zone

The Moldanubian Zone is in the regional geology of Europe a tectonic zone formed during the Variscan or Hercynian Orogeny...

 to the southeast. The Hercynian metamorphism

Metamorphism

Metamorphism is the solid-state recrystallization of pre-existing rocks due to changes in physical and chemical conditions, primarily heat, pressure, and the introduction of chemically active fluids. Mineralogical, chemical and crystallographic changes can occur during this process...

 of the former zone is generally lower grade; that of the latter zone higher grade than that of the Saxothuringian Zone. West of the Vosges the zone is displaced to the north by a major strike-slip fault, the Bray Fault.

The Saxothuringian Zone is in some places transsected by Permo

Permian

The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...

-Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 graben

Graben

In geology, a graben is a depressed block of land bordered by parallel faults. Graben is German for ditch. Graben is used for both the singular and plural....

s and intramontane basins filled with Rotliegend

Rotliegend

The Rotliegend or Rotliegendes is a lithostratigraphic unit of Cisuralian age that is found in the subsurface of large areas in western and central Europe. The Rotliegend mainly consists of sandstone layers...

 sediments and older deposits. The Eger Graben

Eger Graben

The Eger Graben is a geographical unit in the Czech Republic. It runs southwards, parallel to the Ore Mountains and its formation is linked with that of the mountain range.- Topography :...

 in the northwest of Czechia and the Saar-Nahe Basin in western Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 are examples of such structures.

Geology

The Saxothuringian Zone consists of early Paleozoic

Paleozoic

The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...

 marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 sediments that were deposited in the so called Saxothuringian Basin. They were slightly metamorphosed during the Hercynian orogeny. The sedimentary sequence is assumed to be continuous from the Ediacaran

Ediacaran

The Ediacaran Period , named after the Ediacara Hills of South Australia, is the last geological period of the Neoproterozoic Era and of the Proterozoic Eon, immediately preceding the Cambrian Period, the first period of the Paleozoic Era and of the Phanerozoic Eon...

 to the Visean

Viséan

The Visean, Viséan or Visian is an age in the ICS geologic timescale or a stage in the stratigraphic column. It is the second stage of the Mississippian, the lower subsystem of the Carboniferous. The Visean lasted from 345.3 ± 2.1 to 328.3 ± 1.6 Ma...

 (330 million years ago). These metasediments form a wide zone north of the city of Dresden

Dresden

Dresden is the capital city of the Free State of Saxony in Germany. It is situated in a valley on the River Elbe, near the Czech border. The Dresden conurbation is part of the Saxon Triangle metropolitan area....

 in Saxony

Saxony

The Free State of Saxony is a landlocked state of Germany, contingent with Brandenburg, Saxony Anhalt, Thuringia, Bavaria, the Czech Republic and Poland. It is the tenth-largest German state in area, with of Germany's sixteen states....

.

Tectonostratigraphically, gneiss

Gneiss

Gneiss is a common and widely distributed type of rock formed by high-grade regional metamorphic processes from pre-existing formations that were originally either igneous or sedimentary rocks.-Etymology:...

es (high grade metamorphic rocks) and granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

s are found under these metasediments. They crop out as the competent massif

Massif

In geology, a massif is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole...

s of the Erzgebirge and Saxonian Granulite Massif. They were deformed and recrystallized

Recrystallization (geology)

In geology, solid-state recrystallization is a metamorphic process that occurs under situations of intense temperature and pressure where grains, atoms or molecules of a rock or mineral are packed closer together, creating a new crystal structure. The basic composition remains the same...

 during the Cadomian orogeny

Cadomian Orogeny

The Cadomian Orogeny was a tectonic event or series of events in the late Neoproterozoic, about 650-550 Ma, which probably included the formation of mountains. This occurred on the margin of the Gondwana continent, involving one or more collisions of island arcs and accretion of other material at a...

 (in the Ediacaran, 650-550 million years ago) and intruded by felsic

Felsic

The word "felsic" is a term used in geology to refer to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium....

 pluton

Pluton

A pluton in geology is a body of intrusive igneous rock that crystallized from magma slowly cooling below the surface of the Earth. Plutons include batholiths, dikes, sills, laccoliths, lopoliths, and other igneous bodies...

s during the Cambrian

Cambrian

The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...

 and Ordovician

Ordovician

The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...

 (540-420 million years ago).

In some places klippe

Klippe

thumb|right|350px|Schematic overview of a thrust system. The shaded material is called a [[nappe]]. The erosional hole is called a [[window |window or fenster]]. The klippe is the isolated block of the nappe overlying autochthonous material....

s of allochthonous crystalline rocks are found on top of these two units. These klippes are the Münchberg complex, Wildenfels complex and Frankenberg complex. They consisted originally of a sequence of deep-marine (flysch

Flysch

Flysch is a sequence of sedimentary rocks that is deposited in a deep marine facies in the foreland basin of a developing orogen. Flysch is typically deposited during an early stage of the orogenesis. When the orogen evolves the foreland basin becomes shallower and molasse is deposited on top of...

) sediments of Ordovician to Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 age (480-360 million years old) and early Paleozoic mid-oceanic ridge basalts. The latter have been metamorphosed at a high grade (up to eclogite facies). These allochthonous nappes can probably be correlated with the Teplá terrane in the Moldanubian Zone further south.

The Saxothuringian Zone is often also supposed to include the Mid-German Crystalline High

Mid-German Crystalline High

The Mid-German Crystalline High is a structural high in the Paleozoic geology of Germany. The high forms a northeast-southwest oriented zone through Germany, but actual rock outcrops are sparse since Paleozoic basement rocks are in most of central Germany overlain by younger sedimentary rocks...

, which then forms the northern part of the zone and lies directly next to the Rhenohercynian Northern Phyllite Zone. The Mid-German Crystalline High crops out in the Odenwald, the Spessart and the northern Vosges. It consists of Proterozoic

Proterozoic

The Proterozoic is a geological eon representing a period before the first abundant complex life on Earth. The name Proterozoic comes from the Greek "earlier life"...

 orthogneisses and early Paleozoic volcanic

Volcanic rock

Volcanic rock is a rock formed from magma erupted from a volcano. In other words, it is an igneous rock of volcanic origin...

 (amphibolite

Amphibolite

Amphibolite is the name given to a rock consisting mainly of hornblende amphibole, the use of the term being restricted, however, to metamorphic rocks. The modern terminology for a holocrystalline plutonic igneous rocks composed primarily of hornblende amphibole is a hornblendite, which are...

s with MORB-protolith

Protolith

Protolith refers to the precursor lithology of a metamorphic rock.For example, the protolith of a slate is a shale or mudstone. Metamorphic rocks can be derived from any other rock and thus have a wide variety of protoliths. Identifying a protolith is a major aim of metamorphic geology.Sedimentary...

s and tuff

Tuff

Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...

s) and sedimentary

Sedimentary rock

Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....

 (pelite

Pelite

Pelite is old and currently not widely used field terminology for a clayey fine-grained clastic sediment or sedimentary rock, i.e. mud or mudstone. It is equivalent to the Latin-derived term lutite. More commonly, metamorphic geologists currently use pelite for a metamorphosed fine-grained...

s, calcareous schist

Schist

The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is...

s and marble

Marble

Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...

s) rocks that were metamorphosed at high grade during the Hercynian orogeny (up to amphibolite facies). These rocks were intruded by two generations of plutons: Silurian

Silurian

The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...

 to Early Devonian (440-400 million years old) granitoid

Granitoid

A granitoid or granitic rock is a variety of coarse grained plutonic rock similar to granite which mineralogically are composed predominately of feldspar and quartz. Examples of granitoid rocks include granite, quartz monzonite, quartz diorite, syenite, granodiorite and trondhjemite. Many are...

s and middle Carboniferous

Carboniferous

The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...

 (Hercynian, 340-325 million years old) granites.

Literature

; 1992: Phanerozoic structures and events in central Europe, in: (eds.): A Continent Revealed - The European Geotraverse, 297 pp., Cambridge University Press, ISBN 052142948X, pp. 164–179.; 2000: The mid-European segment of the Variscides: tectonostratigraphic units, terrane boundaries and plate tectonic evolution, in: (eds.); Orogenic Processes, Quantification and Modelling in the Variscan Belt, Geological Society of London, Special Publications 179, pp. 35–61.; 1927: Gliederung des varistischen Gebirgsbaues, Abhandlungen des Sächsischen Geologischen Landesamtes 1, pp. 1–39.; 2007: The Variscan orogeny in the Saxo-Thuringian zone - heterogeneous overprint of Cadomian/Paleozoic Peri-Gondwana crust, in: (eds.): The evolution of the Rheic Ocean: from Avalonian-Cadomian active margin to Alleghenian-Variscan collision, Geological Society of America

Geological Society of America

The Geological Society of America is a nonprofit organization dedicated to the advancement of the geosciences. The society was founded in New York in 1888 by Alexander Winchell, John J. Stevenson, Charles H. Hitchcock, John R. Proctor and Edward Orton and has been headquartered at 3300 Penrose...

Special Paper 423 pp. 153–172.; 1995: The Neoproterozoic terranes of Saxony (Germany), Precambrian Research 73, pp. 235–250.; 2001: The Variscan collage and orogeny (480±290 Ma) and the tectonic definition of the Armorica microplate: a review, Terra Nova 13, 122-128.; 1990: Terrane boundaries in the Bohemian Massif: Result of large-scale Variscan shearing, Tectonophysics 177, pp. 151–170.; 1997: Transformation of a magmatic arc and an orogenic root during oblique collision and it’s consequences for the evolution of the European Variscides (Mid-German Crystalline Rise), Geologische Rundschau 86, pp. 2–20.; 2003: Gondwana-derived microcontinents — the constituents of the Variscan and Alpine collisional orogens, Tectonophysics 365, pp. 7–22.; 2010: Pre-Mesozoic Geology of Saxo-Thuringia 488 p. ISBN 978-3-510-65259-4; 2003: Erdgeschichte – Die Entstehung der Kontinente und Ozeane, 325 pp., Walter de Gruyter, Berlin (5^e druk), ISBN 3110176971.