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49-475: The district was created in 1938, when the two former districts Bensheim and Heppenheim were merged. The district is located in the Odenwald mountains, with the 517m high Melibokus as the highest elevation. The Bergstraße is a tourist route which leads from Darmstadt to Wiesloch ; the northern part of this route goes through the district and gave it its name. The coat of arms is split into four quarters. In

98-400: A chilled margin is often found on the intrusion side of the contact, while a contact aureole is found on the country rock side. The chilled margin is much finer grained than most of the intrusion, and may be different in composition, reflecting the initial composition of the intrusion before fractional crystallization, assimilation of country rock, or further magmatic injections modified

147-402: A layered intrusion . The ultimate source of magma is partial melting of rock in the upper mantle and lower crust . This produces magma that is less dense than its source rock. For example, a granitic magma, which is high in silica, has a density of 2.4 Mg/m , much less than the 2.8 Mg/m of high-grade metamorphic rock. This gives the magma tremendous buoyancy, so that ascent of the magma

196-579: A broad inland sea, then followed by sediments from the Late Triassic (or Keuper). The South German Cuesta Land thus formed. When the land in the Odenwald was uplifted again about 180 million years ago, more than 100 m of the sedimentary layering, in parts, was eroded away down to the bedrock , as can still be seen in the western Odenwald. The bedrock here is composed of a number of different rocks, among them gneiss , granite , diorite , gabbro in

245-502: A contact aureole, and often contain xenolithic fragments of country rock suggesting brittle fracturing. Such intrusions are interpreted as occurring at shallow depth, and are commonly associated with volcanic rocks and collapse structures. An intrusion does not crystallize all minerals at once; rather, there is a sequence of crystallization that is reflected in the Bowen reaction series . Crystals formed early in cooling are generally denser than

294-518: A crystallized magma chamber . A pluton that has intruded and obscured the contact between a terrane and adjacent rock is called a stitching pluton . Intrusions are broadly divided into discordant intrusions , which cut across the existing structure of the country rock, and concordant intrusions that intrude parallel to existing bedding or fabric . These are further classified according to such criteria as size, evident mode of origin, or whether they are tabular in shape. An intrusive suite

343-450: A volcanic neck, suggesting that necks tend to form at intersections of dikes where passage of magma is least obstructed. Diatremes and breccia pipes are pipe-like bodies of breccia that are formed by particular kinds of explosive eruptions . As they have reached the surface they are really extrusions, but the non erupted material is an intrusion and indeed due to erosion may be difficult to distinguish from an intrusion that never reached

392-482: Is 1,100 kilometers (680 mi) long and 50 kilometers (31 mi) wide. They are usually formed from magma rich in silica , and never from gabbro or other rock rich in mafic minerals, but some batholiths are composed almost entirely of anorthosite . A sill is a tabular concordant intrusion, typically taking the form of a sheet parallel to sedimentary beds. They are otherwise similar to dikes. Most are of mafic composition, relatively low in silica, which gives them

441-501: Is a group of intrusions related in time and space. Dikes are tabular discordant intrusions, taking the form of sheets that cut across existing rock beds. They tend to resist erosion, so that they stand out as natural walls on the landscape. They vary in thickness from millimeter-thick films to over 300 meters (980 ft) and an individual sheet can have an area of 12,000 square kilometers (4,600 sq mi). They also vary widely in composition. Dikes form by hydraulic fracturing of

490-909: Is a low mountain range in the German states of Hesse , Bavaria and Baden-Württemberg . The Odenwald is located between the Upper Rhine Plain with the Bergstraße and the Hessisches Ried (the northeastern section of the Rhine rift) to the west, the Main and the Bauland (a mostly unwooded area with good soils) to the east, the Hanau-Seligenstadt Basin – a subbasin of the Upper Rhine Rift Valley in

539-399: Is called the room problem , and it remains a subject of active investigation for many kinds of intrusions. The term pluton is poorly defined, but has been used to describe an intrusion emplaced at great depth; as a synonym for all igneous intrusions; as a dustbin category for intrusions whose size or character are not well determined; or as a name for a very large intrusion or for

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588-438: Is coarse-grained ( phaneritic ). Intrusive igneous rocks are classified separately from extrusive igneous rocks, generally on the basis of their mineral content. The relative amounts of quartz , alkali feldspar , plagioclase , and feldspathoid is particularly important in classifying intrusive igneous rocks. Intrusions must displace existing country rock to make room for themselves. The question of how this takes place

637-484: Is connected with monsters (knight Georg fights against the man-eating lindworm near Frankenstein-castle ) and creatures of nature with magic potency (a water spirit changed into a fox near Niedernhausen, the merwoman in the Meerwiese of Waldürn). Secondly the local legend is connected with the genre of the historic saga: a historic person or an original is portrayed anecdotally (the count of Erbach and Luther, resp.

686-404: Is inevitable once enough magma has accumulated. However, the question of precisely how large quantities of magma are able to shove aside country rock to make room for themselves (the room problem ) is still a matter of research. The composition of the magma and country rock and the stresses affecting the country rock strongly influence the kinds of intrusions that take place. For example, where

735-546: Is known as a leisure destination easily accessible from the urban areas of Mannheim and Frankfurt . It is known for its clean thin air and was once known for its health sanitariums. There are many marked hiking paths through the rural areas. Wild blueberries , strawberries and mushrooms are to be found in the forests. The planned extension to the Odenwaldautobahn , that is, the A ;45 ( Dortmund – Aschaffenburg ),

784-537: The Raubacher Joggel , landgrave Ludwig VIII: of Hesse-Darmstadt, robber Hölzerlips ). Thirdly a local tale explains an etiological or original myth (aetiological saga). For example, there is explained: Beside these legends there are two famous and well-known Odenwaldsagas: In the Nibelungenlied (see also Nibelung ) the dragon slayer Siegfried , on a hunting trip (instead of a failed campaign) leading from

833-618: The Burgundian city of Worms into the Odenwald, is murdered by Hagen of Tronje . Since no exact spot for this deed has been handed down, countless communities, especially in the Hessian Odenwald are squabbling over the right to call themselves “Siegfried’s Murder Site”, for example a spring near Gras-Ellenbach ( Siegfriedsbrunnen ), Mossautal-Hüttenthal Lindelbrunnen ) or Heppenheim ( Siegfriedbrunnen ). The ruins of Rodenstein (below-mentioned) and Schnellerts near Fränkisch-Crumbach are

882-750: The Main . Parts of the Odenwald now lay in Roman-ruled Germania Superior . About 159, the Limes was shifted about 30 kilometres (19 miles) eastwards to the Miltenberg – Walldürn – Buchen - Osterburken line. In 260, Roman hegemony fell. The Alamanni were also thrusting into the Odenwald and settling the land between the Main and Neckar, after whom came the Franks . In the 5th century, the Franks, under Clovis I , divided

931-670: The North Sea reached far inland, across the Wetterau Depression into the Rhine Valley. About 2500 BC, there is evidence that the Linear Pottery culture settled along the northern (Gersprenz) and southern (Neckar valley) edges of the Odenwald. About 400 BC, Celts (Gauls) settled throughout southern Germany. Almost all of the Odenwald was covered then with virgin forest , and the outer edges were not settled. Germanic peoples drove

980-757: The Otzberg , the Daumberg and the Katzenbuckel, all extinct volcanoes in the Odenwald. Furthermore, volcanism with acidic rocks has left a legacy of rhyolites near Dossenheim . At roughly the same time, the Central European plate began to tear apart so that the Upper Rhine Rift developed. Even as the Upper Rhine Rift valley still sinks today by just under a millimetre each year, the Odenwald, relatively to that,

1029-821: The Palisades Sill of New York and New Jersey ; the Henry Mountains of Utah ; the Bushveld Igneous Complex of South Africa ; Shiprock in New Mexico ; the Ardnamurchan intrusion in Scotland; and the Sierra Nevada Batholith of California . Because the solid country rock into which magma intrudes is an excellent insulator , cooling of the magma is extremely slow, and intrusive igneous rock

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1078-658: The Variscan , which more than 300 million years ago in the Carboniferous period ran through great parts of Europe . The cause of this orogeny was the collision of Africa ’s and Europe's forerunner continents. In the Triassic , about 200 million years ago, the land sank again, forming the Germanic Basin in which the metre-thick layers of red sandstone could build up . These were later covered over with layers of muschelkalk from

1127-778: The Celts westwards across the Rhine to what is now France . About AD 100, the older Odenwald line of the Neckar-Odenwald Limes was built under Roman Emperor Trajan (98-117). This stretch of the Empire's border ran from Fort Wimpfen in the Valley ( Kastell Wimpfen im Tal ) northwards by way of the Forts of Neckarburken, the lesser forts of Trienz and Robern near Fahrenbach , Fort Oberscheidental, Fort Schloßau, Fort Hesselbach, Fort Würzberg, Fort Eulbach, Fort Hainhaus and Fort Hesselbach to Fort Wörth on

1176-683: The Frankenstein pluton , and so on. In the eastern Odenwald, the red sandstone is all that is left of the sedimentary mixture. Farther east in the Bauland, the muschelkalk deposits still overlie the Early Triassic layers. Furthermore, in the south near Heidelberg , there is still Zechstein under the Early Triassic deposits. Roughly 50 to 60 million years ago, volcanoes formed along the great geological faults . Still bearing witness to this time are

1225-614: The Mümling- and the Neckar-Valley. Songs have been written about the Odenwald: Pluton In geology , an igneous intrusion (or intrusive body or simply intrusion ) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth . Intrusions have a wide variety of forms and compositions, illustrated by examples like

1274-818: The Rhine-Main Lowlands – to the north and the Kraichgau to the south. The part south of the Neckar valley is sometimes called the Kleiner Odenwald ("Little Odenwald"). The northern and western Odenwald belong to southern Hesse, with the south stretching into Baden . In the northeast, a small part lies in Lower Franconia in Bavaria. The Odenwald, along with other parts of the Central German Uplands, belongs to

1323-477: The classification is meaningful for bodies which do not change much in area with depth and that have other features suggesting a distinctive origin and mode of emplacement. Batholiths are discordant intrusions with an exposed area greater than 100 square kilometers (39 sq mi). Some are of truly enormous size, and their lower contacts are very rarely exposed. For example, the Coastal Batholith of Peru

1372-423: The composition of the rest of the intrusion. Isotherms (surfaces of constant temperature) propagate away from the margin according to a square root law, so that if the outermost meter of the magma takes ten years to cool to a given temperature, the next inward meter will take 40 years, the next will take 90 years, and so on. This is an idealization, and such processes as magma convection (where cooled magma next to

1421-461: The contact between intrusion and country rock give clues to the conditions under which the intrusion took place. Catazonal intrusions have a thick aureole that grades into the intrusive body with no sharp margin, indicating considerable chemical reaction between intrusion and country rock, and often have broad migmatite zones. Foliations in the intrusion and the surrounding country rock are roughly parallel, with indications of extreme deformation in

1470-416: The contact is given by the relationship T / T 0 = 1 2 + 1 2 erf ⁡ ( x 2 k t ) {\displaystyle T/T_{0}={\frac {1}{2}}+{\frac {1}{2}}\operatorname {erf} ({\frac {x}{2{\sqrt {kt}}}})} where T 0 {\displaystyle T_{0}} is the initial temperature of

1519-468: The contact sinks to the bottom of the magma chamber and hotter magma takes its place) can alter the cooling process, reducing the thickness of chilled margins while hastening cooling of the intrusion as a whole. However, it is clear that thin dikes will cool much faster than larger intrusions, which explains why small intrusions near the surface (where the country rock is initially cold) are often nearly as fine-grained as volcanic rock. Structural features of

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1568-451: The country rock by magma under pressure, and are more common in regions of crustal tension. Ring dikes and cone sheets are dikes with particular forms that are associated with the formation of calderas . Volcanic necks are feeder pipes for volcanoes that have been exposed by erosion . Surface exposures are typically cylindrical, but the intrusion often becomes elliptical or even cloverleaf -shaped at depth. Dikes often radiate from

1617-510: The country rock. Such intrusions are interpreted as taking placed at great depth. Mesozonal intrusions have a much lower degree of metamorphism in their contact aureoles, and the contact between country rock and intrusion is clearly discernible. Migmatites are rare and deformation of country rock is moderate. Such intrusions are interpreted as occurring at medium depth. Epizonal intrusions are discordant with country rock and have sharp contacts with chilled margins, with only limited metamorphism in

1666-501: The crust is undergoing extension, magma can easily rise into tensional fractures in the upper crust to form dikes. Where the crust is under compression, magma at shallow depth will tend to form laccoliths instead, with the magma penetrating the least competent beds, such as shale beds. Ring dikes and cone sheets form only at shallow depth, where a plug of overlying country rock can be raised or lowered. The immense volumes of magma involved in batholiths can force their way upwards only when

1715-401: The field, there is geochemical evidence. Zircon zoning provides important evidence for determining if a single magmatic event or a series of injections were the methods of emplacement. Large felsic intrusions likely form from melting of lower crust that has been heated by an intrusion of mafic magma from the upper mantle. The different densities of felsic and mafic magma limit mixing, so that

1764-407: The hot material, k is the thermal diffusivity (typically close to 10 m s for most geologic materials), x is the distance from the contact, and t is the time since intrusion. This formula suggests that the magma close to the contact will be rapidly chilled while the country rock close to the contact is rapidly heated, while material further from the contact will be much slower to cool or heat. Thus

1813-482: The job of opening the empty woods up by the central Frankish power ( Carolingian ), Lorsch Abbey from the west, Fulda Monastery from the east and Mosbach Monastery from the south. Amorbach Monastery had the greatest importance for ecclesiastical, cultural and economic development in the eastern Odenwald. In the 9th century in the southeastern Odenwald near the now more thickly settled Bauland, settlements were established. The muschelkalk-new red sandstone mineral boundary

1862-434: The land up into districts. In the 7th and 8th centuries came Christianization by Irish - Scottish and Anglo-Saxon monks ( Pirmin , Boniface ). On the muschelkalk lands of today's Bauland, which favoured agriculture , a broad mesh of settlements arose. The parts of the Odenwald farther in from the rivers, though, with their scant New Red Sandstone soils remained uninhabited. Four Benedictine monasteries were assigned

1911-565: The lion in the bottom-right is the sign of Hesse . German Formula One driver Sebastian Vettel , who is from Heppenheim , has the Bergstraße coat of arms on the front (chin area) of his racing helmet. Bergstraße (electoral district) for the Bundestag . 49°38′27″N 8°38′40″E  /  49.640712°N 8.644330°E  / 49.640712; 8.644330 Odenwald The Odenwald ( German: [ˈoːdn̩valt] )

1960-541: The low viscosity necessary to penetrate between sedimentary beds. A laccolith is a concordant intrusion with a flat base and domed roof. Laccoliths typically form at shallow depth, less than 3 kilometers (1.9 mi), and in regions of crustal compression. Lopoliths are concordant intrusions with a saucer shape, somewhat resembling an inverted laccolith, but they can be much larger and form by different processes. Their immense size promotes very slow cooling, and this produces an unusually complete mineral segregation called

2009-510: The magma is highly silicic and buoyant, and are likely do so as diapirs in the ductile deep crust and through a variety of other mechanisms in the brittle upper crust. Igneous intrusions may form from a single magmatic event or several incremental events. Recent evidence suggests that incremental formation is more common for large intrusions. For example, the Palisades Sill was never a single body of magma 300 meters (980 ft) thick, but

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2058-475: The setting of an Odenwald ghost story: during the night the knight Rodenstein (the Rodensteiner ) flies with a berserker-cornet through the air to prophesy the beginning of a war ( Wild Hunt motif). Countless streams rise in the Odenwald, the longest of which are the following: There are a few bodies of standing water in the Odenwald, among which are the following: Odenwald is twinned with: The Odenwald

2107-405: The silicic magma floats on the mafic magma. Such limited mixing as takes place results in the small inclusions of mafic rock commonly found in granites and granodiorites. An intrusion of magma loses heat to the surrounding country rock through heat conduction. Near the contact of hot material with cold material, if the hot material is initially uniform in temperature, the temperature profile across

2156-401: The surface when magma/lava. The root material of a diatreme is identical to intrusive material nearby, if it exists, that never reached the then surface when formed. A stock is a non-tabular discordant intrusion whose exposure covers less than 100 square kilometers (39 sq mi). Although this seems arbitrary, particularly since the exposure may be only the tip of a larger intrusive body,

2205-572: The top-left it shows the Starkenburg castle, which is one of the major landmarks in the district and a reminiscence of the former Province Starkenburg, a former provinces of the Grand Duchy of Hesse , to which the District once belonged. The flower in the top-right stands for the flower-richness in spring. The cross in the bottom-left derives from the coat of arms of the imperial abbey of Lorsch Abbey , and

2254-407: Was crossed. The following are some theories about the origin of the name Odenwald : Linguists who research phonetic changes and the sound shifts reject theories no. 1 to 3 and prefer 4 or 5; some historians favor no. 2. The numerous Odenwald folk legends are mostly connected with historic geographic sites (castle, town, rock, road and so on) They relate: In some stories the local aspect firstly

2303-401: Was formed from multiple injections of magma. An intrusive body is described as multiple when it forms from repeated injections of magma of similar composition, and as composite when formed of repeated injections of magma of unlike composition. A composite dike can include rocks as different as granophyre and diabase . While there is often little visual evidence of multiple injections in

2352-694: Was never realized. Nevertheless, all these Bundesstraßen run through the Odenwald: Furthermore, the Nibelungenstraße and the Siegfriedstraße run through the Odenwald, partly along the roads listed above. The Odenwald is home to many historic castles and palatial residences. In times past the fortresses on the top of the Odenwald mountains controlled Bergstraße and the Weschnitz-, the Gersprenz-,

2401-479: Was uplifted to the height it has today. Along the faults, the small rivers Gersprenz and Weschnitz have, in part, carved their courses. The Upper Rhine Rift is part of a fracture zone reaching from the Mediterranean Sea to Norway . Right on the edge of the Odenwald, it is roughly 2 500 m deep, but has been filled in to its current height by river and sea sediment, for until about 20 million years ago,

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