Bühlertal is a municipality in the district of Rastatt in Baden-Württemberg in Germany .
29-785: Bühlertal encompasses almost the entirety of the Bühlot Valley and its side valleys on the Western slope of the Northern Black Forest at the ridge to the Upper Rhine Valley from an elevation of 190 meters to 1000 meters above sea level. To the municipality of Buehlertal belong the Obertal (Upper Valley), the settlements Altenberg, Denni (now fused with the Obertal), Boosweg (joined with Obertal), Laengenberg,
58-572: A broad textural category for medium- to coarse-grained metamorphic rock that shows poorly developed schistosity, with compositional layering over 5 millimeters (0.20 in) thick and tending to split into plates over 1 centimeter (0.39 in) thick. Neither definition depends on composition or origin, though rocks poor in platy minerals are more likely to produce gneissose texture. Gneissose rocks thus are largely recrystallized but do not carry large quantities of micas, chlorite or other platy minerals. Metamorphic rock showing stronger schistosity
87-461: A distinct cleavage . Gneisses are common in the ancient crust of continental shields . Some of the oldest rocks on Earth are gneisses, such as the Acasta Gneiss . In traditional English and North American usage, a gneiss is a coarse-grained metamorphic rock showing compositional banding ( gneissic banding ) but poorly developed schistosity and indistinct cleavage . In other words, it
116-454: Is a common and widely distributed type of metamorphic rock . It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks . This rock is formed under pressures anywhere from 2 to 15 kbar, sometimes even more, and temperatures over 300 °C (572 °F). Gneiss nearly always shows a banded texture characterized by alternating darker and lighter colored bands and without
145-475: Is a gneiss resulting from metamorphism of granite, which contains characteristic elliptic or lenticular shear-bound grains ( porphyroclasts ), normally feldspar , surrounded by finer grained material. The finer grained material deforms around the more resistant feldspar grains to produce this texture. Migmatite is a gneiss consisting of two or more distinct rock types, one of which has the appearance of an ordinary gneiss (the mesosome ), and another of which has
174-488: Is a metamorphic rock composed of mineral grains easily seen with the unaided eye, which form obvious compositional layers, but which has only a weak tendency to fracture along these layers. In Europe, the term has been more widely applied to any coarse, mica -poor, high-grade metamorphic rock. The British Geological Survey (BGS) and the International Union of Geological Sciences (IUGS) both use gneiss as
203-518: Is called gneissic banding. The darker bands have relatively more mafic minerals (those containing more magnesium and iron ). The lighter bands contain relatively more felsic minerals (minerals such as feldspar or quartz , which contain more of the lighter elements, such as aluminium , sodium , and potassium ). The banding is developed at high temperature when the rock is more strongly compressed in one direction than in other directions ( nonhydrostatic stress ). The bands develop perpendicular to
232-449: Is classified as schist, while metamorphic rock devoid of schistosity is called a granofels . Gneisses that are metamorphosed igneous rocks or their equivalent are termed granite gneisses, diorite gneisses, and so forth. Gneiss rocks may also be named after a characteristic component such as garnet gneiss, biotite gneiss, albite gneiss, and so forth. Orthogneiss designates a gneiss derived from an igneous rock , and paragneiss
261-613: Is less of a height difference with its neighbouring regions. Its highest peak is the Hornisgrinde at 1,163 m above sea level (NHN) . Woods cover on average 73% of the whole land area and make the Northern Black Forest the most cohesive forested part of the Black Forest, but there are also extensive areas of so-called " Grinden ": treeless, wet heaths , on its highland slopes. Geologically ,
290-517: Is one from a sedimentary rock . Both the BGS and the IUGS use gneissose to describe rocks with the texture of gneiss, though gneissic also remains in common use. For example, a gneissose metagranite or a gneissic metagranite both mean a granite that has been metamorphosed and thereby acquired gneissose texture. The minerals in gneiss are arranged into layers that appear as bands in cross section. This
319-510: Is subjected to extreme temperature and pressure and is composed of alternating layers of sandstone (lighter) and shale (darker), which is metamorphosed into bands of quartzite and mica. Another cause of banding is "metamorphic differentiation", which separates different materials into different layers through chemical reactions, a process not fully understood. Augen gneiss , from the German : Augen [ˈaʊɡən] , meaning "eyes",
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#1732791135939348-731: The Murg , Nagold , Enz , Alb , Acher , Rench , Oos and the upper reaches of the Wolf . In 2001, the Central and Northern Black Forest Nature Park ( Naturpark Schwarzwald Mitte/Nord ) was established and its coverage includes the whole of the Northern Black Forest. In addition, an area of about 10,000 hectares has been designated since 1 January 2014 as the Black Forest National Park . It has numerous highly popular tourist attractions as well as winter sport areas in addition to
377-645: The Black Forest east of Lahr . To the west it is bounded by the Upper Rhine Plain , to the east by the Gäu landscapes. The Northern Black Forest is not the same as the spatial-planning region of Northern Black Forest , which covers the eastern area. With its rather angular – in places trapezoidally-shaped – summits, the Northern Black Forest rises above the Rhine Plain by more than 1,000 m . By contrast, its eastern slopes descend gradually and there
406-458: The amphibolite or granulite facies. These form most of the exposed rock in Archean cratons . Gneiss domes are common in orogenic belts (regions of mountain formation). They consist of a dome of gneiss intruded by younger granite and migmatite and mantled with sedimentary rock. These have been interpreted as a geologic record of two distinct mountain-forming events, with the first producing
435-538: The appearance of an intrusive rock such pegmatite , aplite , or granite the ( leucosome ). The rock may also contain a melanosome of mafic rock complementary to the leucosome. Migmatites are often interpreted as rock that has been partially melted, with the leucosome representing the silica-rich melt, the melanosome the residual solid rock left after partial melting, and the mesosome the original rock that has not yet experienced partial melting. Gneisses are characteristic of areas of regional metamorphism that reaches
464-653: The arable region of the Kraichgau ; its southern boundary with the Central Black Forest (or, in the case of a bipartite division, the Southern Black Forest ) varies depending on the definition or natural regional division used (see also Black Forest ). Earlier, the Northern Black Forest was the entire northern half of the mountain range as far as the line of the Kinzig valley , which divides
493-416: The bottom of the deck in the other direction. These forces stretch out the rock like a plastic , and the original material is spread out into sheets. Per the polar decomposition theorem , the deformation produced by such shearing force is equivalent to rotation of the rock combined with shortening in one direction and extension in another. Some banding is formed from original rock material (protolith) that
522-402: The direction of greatest compression, also called the shortening direction, as platy minerals are rotated or recrystallized into parallel layers. A common cause of nonhydrodynamic stress is the subjection of the protolith (the original rock material that undergoes metamorphism) to extreme shearing force, a sliding force similar to the pushing of the top of a deck of cards in one direction, and
551-509: The dominant rock of the Northern Black Forest is bunter sandstone , although in the deeply incised west its gneiss bedrock reaches the surface. Granites (e.g. Forbach granite) and porphyries have intruded forming crags and tors . The highland regions of the Northern Black Forest are among the regions of the German Central Uplands with the heaviest rainfall (up to 2,200 mm per annum). Its most important rivers are
580-557: The farmsteads Butschenberg und Gertelbach, Grasiweg, Holzmatt, Immenstein, Kohlbergwiese, Mittelberg, Oberer Plaettig (Upper Plaettig), Wiedenfelsen und Wolfshuegel. The hamlet Mistgraben is defunct since 1492, but was mentioned in two baptism records around 1860 as a location. Oldest records about Buehlertal are from 1301 . It belonged to the County of Eberstein . The Margraviate of Baden owned farms in Buehlertal since 1536. In 1688,
609-595: The granite basement and the second deforming and melting this basement to produce the domes. However, some gneiss domes may actually be the cores of metamorphic core complexes , regions of the deep crust brought to the surface and exposed during extension of the Earth's crust . The word gneiss has been used in English since at least 1757. It is borrowed from the German word Gneis , formerly also spelled Gneiss , which
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#1732791135939638-411: The hamlets Buchkopf, Buechelbach (joined with Butschenberg), Laube (bridging Untertal and Obertal), Liehenbach (fused with Untertal), Schafhof, Schoenbuech (joined with Obertal and Buchkopf), Schwarzwasen, Sessgass, Steckenhalt, Untertal, Wintereck and Wolfsbrunnen, the hamlets Eichwald, Freihoefen, Haaberg, Hatzenwoerth, Hirschbach, Hof, Hungerberg, Klotzberg, Lachmatt, Matthaeuser, Schmelz und Sickenwald,
667-521: The middle amphibolite to granulite metamorphic facies . In other words, the rock was metamorphosed at a temperature in excess of 600 °C (1,112 °F) at pressures between about 2 to 24 kbar . Many different varieties of rock can be metamorphosed to gneiss, so geologists are careful to add descriptions of the color and mineral composition to the name of any gneiss, such as garnet-biotite paragneiss or grayish-pink orthogneiss . Continental shields are regions of exposed ancient rock that make up
696-581: The northern third of the Black Forest in Germany or, less commonly today, to the northern half of this mountain region. The Northern Black Forest is bounded in the north by a line from Karlsruhe to Pforzheim and, in the south, by a line running from the Rench valley to Freudenstadt . Its northern boundary largely coincides with the emergence of the extensively forested bunter sandstone strata from
725-681: The ownership of Bühlertal was transferred between the Earl of Eberstein and the Margrave of Baden. It belonged to the county of Bühl, which became the Landkreis Bühl . When the county (Landkreis) of Bühl was dissolved in 1973, Bühlertal became part of the county of Rastatt ( Landkreis Rastatt ). This Rastatt district location article is a stub . You can help Misplaced Pages by expanding it . Northern Black Forest The Northern Black Forest ( German : Nordschwarzwald ) refers to
754-596: The stable cores of continents. The rock exposed in the oldest regions of shields, which is of Archean age (over 2500 million years old), mostly belong to granite-greenstone belts. The greenstone belts contain metavolcanic and metasedimentary rock that has undergone a relatively mild grade of metamorphism, at temperatures of 350–500 °C (662–932 °F) and pressures of 200–500 MPa (2,000–5,000 bar). The greenstone belts are surrounded by high-grade gneiss terrains showing highly deformed low-pressure, high-temperature (over 500 °C (932 °F)) metamorphism to
783-752: The towns named below and the Black Forest High Road and Kaltenbronn . Numerous tarns in the Northern Black Forest are evidence of ice age glacial formations, The best-known is the Mummelsee on the Hornisgrinde. Other tarns are the Ellbachsee, Herrenwieser See , Huzenbacher See , Sankenbachsee , Schurmsee and the Wildsee near Ruhestein. Many of them were also impounded in order to supply excess water for timber rafting which
812-490: The water level of the Nagold. The Kleine Kinzig Dam is used for drinking water, water regulation and electricity generation. Due to the vast preserved natural scenery, the region is popular among hikers. In the winter time, the Northern Black Forest region attracts tourists with the ski resorts Mehliskopf , Hundseck – Bühlertallifte, Kaltenbronn , Simmersfeld . Gneiss Gneiss ( / n aɪ s / nice )
841-712: Was common until the 19th century. Other former tarns have silted up. The Hohlohsee and the Wildsee near Gernsbach-Kaltenbronn are raised bog lakes on the highlands between the Murg and Enz valleys that are only fed by local precipitation. There are several dams in the Northern Black Forest. The Schwarzenbach Dam and the Murg Dam are part of the Rudolf-Fettweis-Werk , a pumped storage and run-of-the-river power station in Forbach. The Nagold Dam regulates
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