Elbe Sandstone Mountains
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Typical Table Mountain the Elbe Sandstone Mountains: Lily Stone
The Elbe Sandstone Mountains ( Czech Labské pískovce or Labské pískovcové Pohoří ) is constructed mainly of sandstone mountain range on the upper reaches of the River Elbe in Saxony ( Germany ) and North Bohemia (Czech Republic). It is about 700 km ² in size and reach heights up to 723 meters above sea level. The German part is generally referred to as Saxon Switzerland, the Czech and Bohemian Switzerland ( České Švýcarsko ). The now more commonly used term " Bohemian-Saxon Switzerland " ( Ceskosaske Švýcarsko ) is derived from it.
Geographical location
The Elbe Sandstone Mountains extends on both sides of the Elbe between the Czech town of Decin ( Děčín ) and the Pirna in Saxony. The eastern boundary is located approximately along a line between Pirna, Hohenstein, Sebnitz, Chřibská, Kamenice by Decin. The western boundary follows from Pirna about the Valley of God Leuba for Erzgebirgskamm and then along the creek Jilovsky ( Eulaubach ) to Decin. The highest peak of the mountain is 723 meters, the Děčínský Sněžník ( High Snow Mountain ) in the Czech part of the mountain, the highest German survey is the Great Zschirnstein ( 561 m).
In the Elbe Sandstone Mountains to the National Park Saxon Switzerland and Bohemian Switzerland.
General
The characteristic feature of this highly rugged Rocky Mountains is his extraordinary wealth of forms in a confined space. Once, in the central European low mountain ranges is the environmentally significant levels of constant change, canyons, mesas and rocky grounds with extant closed forest areas. The variety of different sites, each with her own circumstances with regard to soil and microclimate have spawned an enormous biodiversity. But the diversity of ferns and mosses occurring is unmatched by any other German low mountain range.
The occurrence of Elbsandsteins and thus the Elbe Sandstone Mountains is related to the large-scale deposits of a former sea in the Upper Cretaceous. On the Saxon side, one speaks of the Elbe valley chalk that extends to an area between Meissen -Oberau in the northwest over Dresden and Pirna into Saxon Switzerland and in the form of sandstones, Plänern and other rocks as well as at its base to base gravels ( basal conglomerates ) older origin occurs. Some erosion relics between Reinhardtsgrimma about Dippoldiswalde and Tharandter forest to Siebenlehn form south of Dresden isolated occurrence. They are mainly characterized by sandstones. On Bohemian side, the sandstone deposits continued and make a part of the North Bohemian Cretaceous represents the Cretaceous sediments of the Zittau Basin are assigned on the basis of their regional geological relationships of the North Bohemian Cretaceous. The sediment sequences from the Cretaceous sea can be traced as far as Moravia in other landscape areas in the Czech Republic. Together, these deposits form the Saxon-Bohemian Cretaceous zone. In the Czech Elbe Valley chalk geology is described as an offshoot of the Bohemian Cretaceous Basin.
Geology
The diverse variety of forms of the sandstone landscape is a result of physico-chemical and biological processes of erosion of rocks that were formed essentially of the deposited during the Cretaceous sands.
The area of the Elbe sandstone is within the same zone (Elbe lineament ) so that the area of a geological fault zone between the Lusatian granite massif in the north-east and the crystalline rocks of the Ore Mountains in the southwest. The several -kilometer-wide fault zone runs in hercynischer direction from southeast to northwest and is tectonically active since the Cambrian.
A since the Pennsylvanian (about 320 mya ) onset mainland era, which was characterized by weathering and erosion, was in the Jurassic (about 180 mya ) Durche interrupted a brief flooding. The marine sediments deposited here, mainly limestones, have been preserved on the northeast edge of the same zone in the region of the Lusatian Thrust in the form of small globules, some of which are present at the surface.
At the beginning of the Upper Cretaceous implemented in the Cenomanian (about 95 mya ) a reduction processes that enabled the advance of a Cretaceous sea from the west. The tributaries of the sea and marine currents, transporting over a period of about 8 million years away silt, sand, gravel, crushed stone and plants leading tone in the further lowering shallow sea zone. By diagenetic processes at different pressure regimes, there was the formation of sandstone layers. Among the older deposits also included uranium leading clays and silts of the lower and Mittelcenomanium that were obtained in the uranium mine Königstein 1963-1990.
In Obercenomanium formed in the same zone, a strait that connected the North German -Polish sedimentary basins, and the sedimentary basins in the area of Bohemia / Moravia ( marginal basins of the Tethys Sea ). The land masses in the east of the strait were the Westsudetische island ( Lusatian mountains, Jizera Mountains, Giant Mountains). In the West, the Central European Island situated (Western Erzgebirge, Fichtelgebirge, the Bavarian Forest ), the limit represents the marine incursions of the Cenomanian ranged far beyond the present geographical boundaries of the Elbe Sandstone Mountains. Sandstone deposits of this period are found today as erosion relics, among others in the Dippoldiswalder heath and forest in Tharandter.
Surface development it were especially the sandy deposits of the Turonian and Coniacian, which were determined by a repeated change of marine incursions and marine retreats. This led to the alternate deposition of slightly weathered clayey- silty ( and partly calcareous ) sediments and stable sandy- gravelly sediments. While the clayey- silty sediments often faced low thicknesses in the decimeter, acquired the sandy sediment thicknesses of up to 120 meters. The clayey- silty sediments affect water thawing and thus encourage the weathering. These layers occur in the landscape as ledges or terraces, coves, caves and bedding planes ( in individual cases) than stone bridges in appearance. The sandy- gravelly sediments, however, are much more resistant, made them the striking rock walls of the Elbe Sandstone Mountains are built.
In the Saxon area of the Elbe sandstone deposits of the Turonian and Coniacian were trained in a total thickness of up to 550 meters. The most recent ( and last ) deposits can be found here, among others in the summit area of the small and the great Winterberg ( widths up to 80 meters), in the uppermost layers of Schramm and Affensteine ( widths up to 30 meters), in the summit area of the Rathener rock mining area (including locomotive ), the fire and ( low powerful) than top layer of individual mesas (including lilies stone, Pfaffenstein ).
In the Czech part of the Elbe sandstone sedimentation occurred until the Santonian in and also reached thicknesses of up to 600 meters. The most recent ( and last ) layers of weathered Sedimentparketes but stronger than in Saxon Switzerland, remained so just get layers to the Oberturonium. Only in the area of Prebischtor ( Pravčická brána ) and wing wall ( Křídelní stěna ) -rich layers of the Coniacian in the area of the Great Winterberg also up in the Bohemian Switzerland.
In Coniacian it happened again to uplift operations, which caused an outflow of Cretaceous marine and thus an end to the sedimentation. This left the sea floor in the form of a layered but still undifferentiated sandstone slab.
The stratification of the Elbsandsteins fully described for the first time by Friedrich Lamprecht is by changing horizontal structural differences ( deposits of clay minerals, grain sizes of quartz, differences in grain binding ) as well as a typical but mostly low Fossilf | characterizes EADERSHIP and more or less water-bearing layers. The name of the individual layers was carried out by Lamprecht with the letter " a" to " e" ( from bottom to the hanging wall ) for the stable sandy- gravelly sediments and with the Greek letter " α " to " δ " for the fine-grained and easily weathered clay - silty sediments. This division is on the Czech part of the Elbe Sandstone Mountains, however, only limited relevance, since the layer boundaries are not marked distinctively and consistently, particularly in rechtselbischen part. In contrast to the Saxon Switzerland, the sediments are mixed vertically stronger in terms of their grain size here, which indicates once heavily changing ocean currents in the Cretaceous sea.
When looking at the Affensteine the multilevel structure is clearly visible: the sandstone wall of the stage rises above a table covered with talus base of the wall d, in the upper third marks a partly wooded terrace intermediate δ2 with the promenade, over the sandstone wall of the stage rises e
The view of the stone circle shows the already heavily eroded rock crown of step d, which is seated on a heap of rubble stage c.
The Polenz has been cut on the Waltersdorfer mill deep into the sandstone layers e to b ( bottom ).
The valley section of the same ranges in Schmilka up in the sandstone layer a1, also rises with the rechtselbisch Schrammsteine the complete layer sequence up to step e ( High and Middle Torstein ).
The intermediate horizons δ2 and γ3 favor of water-bearing horizons, the sandstone weathering and cave formation. The floor of the barn belongs to layer γ3, the weathering worked from both sides of the rock riffs, so that a rock arch was built.
The (regression ) of the Cretaceous sea followed almost time a walking toward south-southwest elevation of the Lusatian granite massif that pushed from the north and the north-east part evidence of the Cretaceous sandstone slab and this pushed down until they broke. The fracture zone at the northern and north-eastern boundary of the Elbe sandstone (also called Lusatian Thrust ) as the Lusatian fault called. It runs approximately along a line of Pillnitz on Hohenstein and Hinterhermsdorf towards Krasna Lipa ( Schönlinde ). In Hohenstein is located on the western flank of the Polenz on the so-called Wartenberg road the only geologic outcrop on which the location of the Lusatian granite above the Cretaceous sandstone is directly visible.
When sliding the granite rocks to the Cretaceous sandstone slab occurred along the Lusatian fault partially for erection and inclination of the sandstone layers. Striking this particular will to the High love that up to 30 ° was a sharp peak shape by the dip of the sandstone layers in the south- southeast and by the fact stands out clearly from Table Mountain sandstone relief of the other mountains of the Elbe Sandstone Mountains. West of Vlčí hora ( Wolfsberg ) there was even a reverse fault of the original horizontally supporting sandstone layers.
At the same time older rocks of Permian, Jurassic, Cenomanian and Turonian were along the Lusatian fault drags up and came to the surface. Economic importance gained thereby the concentration of limestone from the Jurassic, which were obtained in the past on several occasions by mining, among others as at Zeschnig and Saupsdorf, near the Upper Mill Hinterhermsdorf and northeast of Doubice ( Daubitz ).
In the Tertiary, especially the adjacent area of the Bohemian Uplands and the Lusatian Mountains was formed by intense volcanic activity and influences, but individual magma intrusions broke through the sandstone panel of the Elbe Sandstone Mountains. The most striking evidence of this geological period are mainly basaltic cone mountains Růžovský vrch (Rosenberg ), Cottaer Spitzberg and space mountain, but also the Great and Little Winterberg.
At the southwestern edge of the sandstone slab was lifted at the Karsdorfer disorder by more than 200 meters, which means the plate tipped even stronger and the slope of the same stream increased. The water masses were digging with their riverbed valleys into the rock and carried in places to the formation of the rock walls. Over time, reduced the gap; the river bed of the same stream broadened and changed again and again, even by glacial climatic effects due to his history.
The mineral composition of sandstone deposits has a direct impact on the morphology of the terrain. The fine-grained clayey- silty type of bond between the quartz graining caused embankments and slopes with terracing. The pebbly bound sandstone beds are typical for the formation of walls and cliffs. Small variations in the binder composition in the rock may affect visible in the landscape.
Its characteristic square - Frequency owes Elbsandstone a wide constant horizontal stratification ( Bankung ) and the vertical fracture. Bernhard Cotta writes in 1839 in his Notes on the geognostical Map commented: " Verticale fissures and columns intersect among themselves quite at right angles, the dare-right layers, and thus arises that segregation in parallelepiped body, which has given rise to the name of ashlar sandstone reason. "
The term ashlar sandstone mountains, introduced by Hanns Bruno Geinitz 1849, is a historic geological term for similar sandstone deposits, but was also used in the context of the Elbe Sandstone Mountains.
The crevices formed by long periods of tectonic stresses on the entire sandstone slab of the mountain. This fracture network pervades, in two areas of the mountain with different directions in a relatively regular shape these sandstone deposits. Following onset of weathering processes very different nature and mutual complex superposition ( washouts, frost and salt blasting, wind, solution processes with encrustations and biogenic and microbial agents ) have further shaped the rock surfaces. It emerged, for example, collapse of caves, small hole-like depressions ( alveoli) with sand clocks, fireplaces, columns and rugged mighty walls. A variety of morphological formations in the rock landscape of the Elbe Sandstone Mountains are discussed as a result of karstification in terms of their origin. Particularly frequent furrows with parallel ridges, they have the air of carts structures, as well as extensive cave systems offer the polygenic and polymorphic erosion landscape of the Elbe Sandstone Mountains this important clues. They are sometimes referred to with the term pseudo- karst. However, the transfer of the concept to some forms of erosion in the sandstone of the Elbe Sandstone Mountains and the derived mode of explanation are controversial. Czech geologists be stated for quarzitisch bound sandstone areas in the northern part of the Bohemian Cretaceous Basin karst phenomena in the form of spherical cavities and cave formations. They therefore formed by solution processes of water in complex interaction with iron compounds from neighboring or intruded magmatic- volcanic rocks. On the basis of these processes, the variety of the relief is explained in those sandstone areas. The Elbe Sandstone Mountains is the largest Cretaceous sandstone erosion complex in Europe.
The anthropogenic changes through the 1,000 -year-long sand quarrying contributed in some areas of the Elbe sandstone additionally contributes to the shaping of the present day landscape. The crevasses ( called by the quarrymen Loose ) played an important role, as they claimed a natural limitation on the wall precipitation and Rohblockzurichtung helpful.
Conservation
Large parts of the Elbe Sandstone Mountains are protected by law. In Germany there is the national park region Saxon Switzerland which is established from the two-part 1990 93 km ² national park Saxon Switzerland (NLP ) and founded in 1956 the surrounding 287 km ² nature reserve ( LSG ). The German mountain part was also prädikatisiert in May 2006 by the Academy of Earth Sciences to Hannover as one of the 77 most important national geological sites in Germany.
In the Bohemian mountain wing consists in the northeastern area since 1972, the nature reserve " Chranena krajinná oblast Labské pískovce " ( nature reserve Elbe Sandstone Rocks ) with an area of 324 km ². In 2000, the " Národní park České Švýcarsko " ( National Park Bohemian Switzerland ) was established with an area of 79 km ², making thus are approximately 700 km ² total area of the mountain as a natural and cultural landscape under protection.