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96-641: This national park is located on the eastern edge of the Alps and on the western edge of the Little Hungarian Plain . Because of its location, the area has, for centuries, been a buffer zone between the great powers of Europe. In 1994, as the first national park in Austria, it received a category II label from the IUCN. The Austrian part of the national park was declared a UNESCO World Heritage Site in 2001. The area of

192-400: A (usually small) angle. Sometimes multiple sets of layers with different orientations exist in the same rock, a structure called cross-bedding . Cross-bedding is characteristic of deposition by a flowing medium (wind or water). The opposite of cross-bedding is parallel lamination, where all sedimentary layering is parallel. Differences in laminations are generally caused by cyclic changes in

288-600: A crescent shaped geographic feature of central Europe that ranges in an 800 km (500 mi) arc (curved line) from east to west and is 200 km (120 mi) in width. The mean height of the mountain peaks is 2.5 km (1.6 mi). The range stretches from the Mediterranean Sea north above the Po basin, extending through France from Grenoble , and stretching eastward through mid and southern Switzerland. The range continues onward toward Vienna , Austria, and southeast to

384-424: A diagenetic structure common in carbonate rocks is a stylolite . Stylolites are irregular planes where material was dissolved into the pore fluids in the rock. This can result in the precipitation of a certain chemical species producing colouring and staining of the rock, or the formation of concretions . Concretions are roughly concentric bodies with a different composition from the host rock. Their formation can be

480-716: A major commercial and military road between Western Europe and Italy. The pass was crossed by many troops on their way to the Italian peninsula. From Constantine I , Pepin the Short and Charlemagne to Henry IV , Napoléon and more recently the German Gebirgsjägers during World War II . Now the pass has been supplanted by the Fréjus Highway Tunnel (opened 1980) and Rail Tunnel (opened 1871). The Saint Gotthard Pass crosses from Central Switzerland to Ticino ; in 1882

576-687: A man was in 1788; the first ascent by a woman was in 1808. By the mid-1850s Swiss mountaineers had ascended most of the peaks and were eagerly sought as mountain guides. Edward Whymper reached the top of the Matterhorn in 1865 (after seven attempts), and in 1938 the last of the six great north faces of the Alps was climbed with the first ascent of the Eiger Nordwand (north face of the Eiger). Important geological concepts were established as naturalists began studying

672-463: A particular sedimentary environment. Examples of bed forms include dunes and ripple marks . Sole markings, such as tool marks and flute casts, are grooves eroded on a surface that are preserved by renewed sedimentation. These are often elongated structures and can be used to establish the direction of the flow during deposition. Ripple marks also form in flowing water. There can be symmetric or asymmetric. Asymmetric ripples form in environments where

768-507: A permanent laboratory exists inside a glacier under the Jungfraujoch , devoted exclusively to the study of Alpine glaciers. Sedimentary rock Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface , followed by cementation . Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form

864-465: A red colour does not necessarily mean the rock formed in a continental environment or arid climate. The presence of organic material can colour a rock black or grey. Organic material is formed from dead organisms, mostly plants. Normally, such material eventually decays by oxidation or bacterial activity. Under anoxic circumstances, however, organic material cannot decay and leaves a dark sediment, rich in organic material. This can, for example, occur at

960-484: A rock is usually expressed with the Wentworth scale, though alternative scales are sometimes used. The grain size can be expressed as a diameter or a volume, and is always an average value, since a rock is composed of clasts with different sizes. The statistical distribution of grain sizes is different for different rock types and is described in a property called the sorting of the rock. When all clasts are more or less of

1056-465: A sediment after its initial deposition. This includes compaction and lithification of the sediments. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and is characterized by bioturbation and mineralogical changes in the sediments, with only slight compaction. The red hematite that gives red bed sandstones their color is likely formed during eogenesis. Some biochemical processes, like

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1152-463: A sedimentary rock are called sediment , and may be composed of geological detritus (minerals) or biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or mass movement , which are called agents of denudation . Biological detritus

1248-431: A sedimentary rock may have been present in the original sediments or may formed by precipitation during diagenesis. In the second case, a mineral precipitate may have grown over an older generation of cement. A complex diagenetic history can be established by optical mineralogy , using a petrographic microscope . Carbonate rocks predominantly consist of carbonate minerals such as calcite, aragonite or dolomite . Both

1344-516: A small-scale property of a rock, but determines many of its large-scale properties, such as the density , porosity or permeability . The 3D orientation of the clasts is called the fabric of the rock. The size and form of clasts can be used to determine the velocity and direction of current in the sedimentary environment that moved the clasts from their origin; fine, calcareous mud only settles in quiet water while gravel and larger clasts are moved only by rapidly moving water. The grain size of

1440-952: A term for a fissile mudrock (regardless of grain size) although some older literature uses the term "shale" as a synonym for mudrock. Biochemical sedimentary rocks are created when organisms use materials dissolved in air or water to build their tissue. Examples include: Chemical sedimentary rock forms when mineral constituents in solution become supersaturated and inorganically precipitate . Common chemical sedimentary rocks include oolitic limestone and rocks composed of evaporite minerals, such as halite (rock salt), sylvite , baryte and gypsum . This fourth miscellaneous category includes volcanic tuff and volcanic breccias formed by deposition and later cementation of lava fragments erupted by volcanoes, and impact breccias formed after impact events . Alternatively, sedimentary rocks can be subdivided into compositional groups based on their mineralogy: Sedimentary rocks are formed when sediment

1536-417: A texture, only the average size of the crystals and the fabric are necessary. Most sedimentary rocks contain either quartz ( siliciclastic rocks) or calcite ( carbonate rocks ). In contrast to igneous and metamorphic rocks, a sedimentary rock usually contains very few different major minerals. However, the origin of the minerals in a sedimentary rock is often more complex than in an igneous rock. Minerals in

1632-582: A tunnel 1.6 km (1 mi) long was built along the route of the pass in the mid-19th century. With a summit of 2,469 m (8,100 ft), the Great St Bernard Pass is one of the highest in the Alps, crossing the Italian-Swiss border east of the Pennine Alps along the flanks of Mont Blanc. The pass was used by Napoleon Bonaparte to cross 40,000 troops in 1800. The Mont Cenis pass has been

1728-425: A valuable indicator of the biological and ecological environment that existed after the sediment was deposited. On the other hand, the burrowing activity of organisms can destroy other (primary) structures in the sediment, making a reconstruction more difficult. Secondary structures can also form by diagenesis or the formation of a soil ( pedogenesis ) when a sediment is exposed above the water level. An example of

1824-406: A yearly compensation for leaving these plots unused. The national park has a visitor information centre, which is located in the town of Illmitz . The national park is known for its varied birdlife, with some of the 178 breeding species found at their westernmost edges of their distribution, whilst the national park also attracts regular vagrant bird species, which form a substantial proportion of

1920-503: Is deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension . This sediment is often formed when weathering and erosion break down a rock into loose material in a source area. The material is then transported from the source area to the deposition area. The type of sediment transported depends on the geology of the hinterland (the source area of the sediment). However, some sedimentary rocks, such as evaporites , are composed of material that form at

2016-629: Is sedimentary rock formed during mountain building. The Alpine orogeny occurred in ongoing cycles through to the Paleogene causing differences in folded structures, with a late-stage orogeny causing the development of the Jura Mountains . A series of tectonic events in the Triassic, Jurassic and Cretaceous periods caused different paleogeographic regions. The Alps are subdivided by different lithology (rock composition) and nappe structures according to

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2112-478: Is a stub . You can help Misplaced Pages by expanding it . Alps The Alps ( / æ l p s / ) are one of the highest and most extensive mountain ranges in Europe , stretching approximately 1,200 km (750 mi) across eight Alpine countries (from west to east): Monaco , France , Switzerland , Italy , Liechtenstein , Germany , Austria and Slovenia . The Alpine arch extends from Nice on

2208-421: Is a structure where beds with a smaller grain size occur on top of beds with larger grains. This structure forms when fast flowing water stops flowing. Larger, heavier clasts in suspension settle first, then smaller clasts. Although graded bedding can form in many different environments, it is a characteristic of turbidity currents . The surface of a particular bed, called the bedform , can also be indicative of

2304-409: Is called bedding . Single beds can be a couple of centimetres to several meters thick. Finer, less pronounced layers are called laminae, and the structure a lamina forms in a rock is called lamination . Laminae are usually less than a few centimetres thick. Though bedding and lamination are often originally horizontal in nature, this is not always the case. In some environments, beds are deposited at

2400-471: Is estimated to be only 8% of the volume of the crust. Sedimentary rocks are only a thin veneer over a crust consisting mainly of igneous and metamorphic rocks . Sedimentary rocks are deposited in layers as strata , forming a structure called bedding . Sedimentary rocks are often deposited in large structures called sedimentary basins . Sedimentary rocks have also been found on Mars . The study of sedimentary rocks and rock strata provides information about

2496-429: Is higher when the sedimentation rate is high (so that a carcass is quickly buried), in anoxic environments (where little bacterial activity occurs) or when the organism had a particularly hard skeleton. Larger, well-preserved fossils are relatively rare. Fossils can be both the direct remains or imprints of organisms and their skeletons. Most commonly preserved are the harder parts of organisms such as bones, shells, and

2592-491: Is mirrored by the broad categories of rudites , arenites , and lutites , respectively, in older literature. The subdivision of these three broad categories is based on differences in clast shape (conglomerates and breccias), composition (sandstones), or grain size or texture (mudrocks). Conglomerates are dominantly composed of rounded gravel, while breccias are composed of dominantly angular gravel. Sandstone classification schemes vary widely, but most geologists have adopted

2688-498: Is of continental European origin, above which are stacked marine sediment nappes, topped off by nappes derived from the African plate. The Matterhorn is an example of the ongoing orogeny and shows evidence of great folding. The tip of the mountain consists of gneisses from the African plate; the base of the peak, below the glaciated area, consists of European basement rock. The sequence of Tethyan marine sediments and their oceanic basement

2784-401: Is reduced. Sediments are typically saturated with groundwater or seawater when originally deposited, and as pore space is reduced, much of these connate fluids are expelled. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under the greatest strain, and the strained mineral is more soluble than the rest of

2880-608: Is sandwiched between rock derived from the African and European plates. The core regions of the Alpine orogenic belt have been folded and fractured in such a manner that erosion produced the characteristic steep vertical peaks of the Swiss Alps that rise seemingly straight out of the foreland areas. Peaks such as Mont Blanc, the Matterhorn, and high peaks in the Pennine Alps, the Briançonnais, and Hohe Tauern consist of layers of rock from

2976-493: Is the most stable, followed by feldspar , micas , and finally other less stable minerals that are only present when little weathering has occurred. The amount of weathering depends mainly on the distance to the source area, the local climate and the time it took for the sediment to be transported to the point where it is deposited. In most sedimentary rocks, mica, feldspar and less stable minerals have been weathered to clay minerals like kaolinite , illite or smectite . Among

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3072-523: The Adriatic Sea and Slovenia . To the south it dips into northern Italy and to the north extends to the southern border of Bavaria in Germany. In areas like Chiasso , Switzerland, and Allgäu , Bavaria, the demarcation between the mountain range and the flatlands are clear; in other places such as Geneva , the demarcation is less clear. The Alps are found in the following countries: Austria (28.7% of

3168-892: The Colle della Maddalena , to the north. Upon reaching the Swiss border, the line of the main chain heads approximately east-northeast, a heading it follows until its end near Vienna. The northeast end of the Alpine arc, directly on the Danube , which flows into the Black Sea, is the Leopoldsberg near Vienna. In contrast, the southeastern part of the Alps ends on the Adriatic Sea in the area around Trieste towards Duino and Barcola . The Alps have been crossed for war and commerce, and by pilgrims, students and tourists. Crossing routes by road, train, or foot are known as passes , and usually consist of depressions in

3264-502: The Gotthard Base Tunnel , was opened, which connects Erstfeld in canton of Uri with Bodio in canton of Ticino by two single tubes of 57.1 km (35.5 mi). It is the first tunnel that traverses the Alps on a flat route. From 11 December 2016, it has been part of the regular railway timetable and used hourly as standard ride between Basel / Lucerne / Zürich and Bellinzona / Lugano / Milan . The highest pass in

3360-585: The Oxford English Dictionary , the Latin Alpes might derive from a pre-Indo-European word * alb "hill"; "Albania" is a related derivation. Albania, a name not native to the region known as the country of Albania , has been used as a name for several mountainous areas across Europe. In Roman times , "Albania" was a name for the eastern Caucasus , while in the English languages "Albania" (or "Albany")

3456-733: The Pangaean supercontinent consisted of a single tectonic plate ; it broke into separate plates during the Mesozoic Era and the Tethys sea developed between Laurasia and Gondwana during the Jurassic Period. The Tethys was later squeezed between colliding plates causing the formation of mountain ranges called the Alpide belt , from Gibraltar through the Himalayas to Indonesia —a process that began at

3552-460: The Romanticists , followed by the golden age of alpinism as mountaineers began to ascend the peaks of the Alps. The Alpine region has a strong cultural identity. Traditional practices such as farming, cheesemaking, and woodworking still thrive in Alpine villages. However, the tourist industry began to grow early in the 20th century and expanded significantly after World War II, eventually becoming

3648-705: The Simplon Pass , and the Stelvio Pass . Crossing the Italian-Austrian border, the Brenner Pass separates the Ötztal Alps and Zillertal Alps and has been in use as a trading route since the 14th century. The lowest of the Alpine passes at 985 m (3,232 ft), the Semmering crosses from Lower Austria to Styria ; since the 12th century when a hospice was built there, it has seen continuous use. A railroad with

3744-459: The history of life . The scientific discipline that studies the properties and origin of sedimentary rocks is called sedimentology . Sedimentology is part of both geology and physical geography and overlaps partly with other disciplines in the Earth sciences , such as pedology , geomorphology , geochemistry and structural geology . Sedimentary rocks can be subdivided into four groups based on

3840-682: The organic material of a dead organism undergoes chemical reactions in which volatiles such as water and carbon dioxide are expulsed. The fossil, in the end, consists of a thin layer of pure carbon or its mineralized form, graphite . This form of fossilisation is called carbonisation . It is particularly important for plant fossils. The same process is responsible for the formation of fossil fuels like lignite or coal. Structures in sedimentary rocks can be divided into primary structures (formed during deposition) and secondary structures (formed after deposition). Unlike textures, structures are always large-scale features that can easily be studied in

3936-597: The 15 km-long (9.3 mi) Saint Gotthard Railway Tunnel was opened connecting Lucerne in Switzerland, with Milan in Italy. 98 years later followed Gotthard Road Tunnel (16.9 km (10.5 mi) long) connecting the A2 motorway in Göschenen on the north side with Airolo on the south side, exactly like the railway tunnel. On 1 June 2016 the world's longest railway tunnel,

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4032-651: The 20th century Robert Parker wrote a well-known work about the rock crystals of the Swiss Alps; at the same period a commission was established to control and standardize the naming of Alpine minerals. In the Miocene Epoch the mountains underwent severe erosion because of glaciation, which was noted in the mid-19th century by naturalist Louis Agassiz who presented a paper proclaiming the Alps were covered in ice at various intervals—a theory he formed when studying rocks near his Neuchâtel home which he believed originated to

4128-668: The 29 "four-thousanders" with at least 300 m (984 ft) of prominence. While Mont Blanc was first climbed in 1786 and the Jungfrau in 1811, most of the Alpine four-thousanders were climbed during the second half of the 19th century, notably Piz Bernina (1850), the Dom (1858), the Grand Combin (1859), the Weisshorn (1861) and the Barre des Écrins (1864); the ascent of the Matterhorn in 1865 marked

4224-481: The Alpine region. The cinnabar deposits in Slovenia are a notable source of cinnabar pigments. Alpine crystals have been studied and collected for hundreds of years and began to be classified in the 18th century. Leonhard Euler studied the shapes of crystals, and by the 19th-century crystal hunting was common in Alpine regions. David Friedrich Wiser amassed a collection of 8000 crystals that he studied and documented. In

4320-689: The Alps are difficult to quantify and likely to vary significantly in space and time. The Alps are a source of minerals that have been mined for thousands of years. In the 8th to 6th centuries, BC during the Hallstatt culture , Celtic tribes mined copper; later the Romans mined gold for coins in the Bad Gastein area. Erzberg in Styria furnishes high-quality iron ore for the steel industry. Crystals, such as cinnabar , amethyst , and quartz , are found throughout much of

4416-754: The Alps goes back to the Palaeolithic era. A mummified man ("Ötzi") , determined to be 5,000 years old, was discovered on a glacier at the Austrian–Italian border in 1991. By the 6th century BC, the Celtic La Tène culture was well established. Hannibal notably crossed the Alps with a herd of elephants, and the Romans had settlements in the region. In 1800, Napoleon crossed one of the mountain passes with an army of 40,000. The 18th and 19th centuries saw an influx of naturalists, writers, and artists, in particular,

4512-762: The Austroalpine peaks underwent an event in the Cretaceous Period, the two areas show distinct differences in nappe formations. Flysch deposits in the Southern Alps of Lombardy probably occurred in the Cretaceous or later. Peaks in France, Italy and Switzerland lie in the "Houillière zone", which consists of basement with sediments from the Mesozoic Era. High "massifs" with external sedimentary cover are more common in

4608-497: The Dott scheme, which uses the relative abundance of quartz, feldspar, and lithic framework grains and the abundance of a muddy matrix between the larger grains. Six sandstone names are possible using the descriptors for grain composition (quartz-, feldspathic-, and lithic-) and the amount of matrix (wacke or arenite). For example, a quartz arenite would be composed of mostly (>90%) quartz grains and have little or no clayey matrix between

4704-509: The Eastern and South-Western Alps. The underlying mechanisms that jointly drive the present-day uplift pattern are the isostatic rebound due to the melting of the last glacial maximum ice-cap or long-term erosion, detachment of the Western Alpine subducting slab, mantle convection as well as ongoing horizontal convergence between Africa and Europe, but their relative contributions to the uplift of

4800-698: The French–Italian border, and at 4,809 m (15,778 ft) is the highest mountain in the Alps. The Alpine region area contains 128 peaks higher than 4,000 m (13,000 ft) . The altitude and size of the range affect the climate in Europe; in the mountains, precipitation levels vary greatly and climatic conditions consist of distinct zones. Wildlife such as ibex live in the higher peaks to elevations of 3,400 m (11,155 ft), and plants such as edelweiss grow in rocky areas in lower elevations as well as in higher elevations. Evidence of human habitation in

4896-619: The Greek goddess Alphito , whose name is related to alphita , the "white flour"; alphos , a dull white leprosy; and finally the Proto-Indo-European word *albʰós . Similarly, the river god Alpheus is also supposed to derive from the Greek alphos and means whitish. In his commentary on the Aeneid of Virgil , the late fourth-century grammarian Maurus Servius Honoratus says that all high mountains are called Alpes by Celts. According to

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4992-591: The Western Alps and were affected by Neogene Period thin-skinned thrusting whereas the Eastern Alps have comparatively few high peaked massifs. Similarly the peaks in eastern Switzerland extending to western Austria (Helvetic nappes) consist of thin-skinned sedimentary folding that detached from former basement rock. In simple terms, the structure of the Alps consists of layers of rock of European, African, and oceanic (Tethyan) origin. The bottom nappe structure

5088-470: The activity of bacteria , can affect minerals in a rock and are therefore seen as part of diagenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sediments come under increasing overburden (lithostatic) pressure from overlying sediments. Sediment grains move into more compact arrangements, grains of ductile minerals (such as mica ) are deformed, and pore space

5184-672: The alps is the Col de l'Iseran in Savoy (France) at 2,770 m (9,088 ft), followed by the Stelvio Pass in northern Italy at 2,756 m (9,042 ft); the road was built in the 1820s. The Union Internationale des Associations d'Alpinisme (UIAA) has defined a list of 82 "official" Alpine summits that reach at least 4,000 m (13,123 ft). The list includes not only mountains, but also subpeaks with little prominence that are considered important mountaineering objectives. Below are listed

5280-399: The bottom of deep seas and lakes. There is little water mixing in such environments; as a result, oxygen from surface water is not brought down, and the deposited sediment is normally a fine dark clay. Dark rocks, rich in organic material, are therefore often shales. The size , form and orientation of clasts (the original pieces of rock) in a sediment is called its texture . The texture is

5376-499: The cement and the clasts (including fossils and ooids ) of a carbonate sedimentary rock usually consist of carbonate minerals. The mineralogy of a clastic rock is determined by the material supplied by the source area, the manner of its transport to the place of deposition and the stability of that particular mineral. The resistance of rock-forming minerals to weathering is expressed by the Goldich dissolution series . In this series, quartz

5472-421: The cement to produce secondary porosity . At sufficiently high temperature and pressure, the realm of diagenesis makes way for metamorphism , the process that forms metamorphic rock . The color of a sedimentary rock is often mostly determined by iron , an element with two major oxides: iron(II) oxide and iron(III) oxide . Iron(II) oxide (FeO) only forms under low oxygen ( anoxic ) circumstances and gives

5568-852: The central and western portions. The variances in nomenclature in the region spanned by the Alps make classification of the mountains and subregions difficult, but a general classification is that of the Eastern Alps and Western Alps with the divide between the two occurring in eastern Switzerland according to geologist Stefan Schmid, near the Splügen Pass . The highest peaks of the Western Alps and Eastern Alps, respectively, are Mont Blanc, at 4,810 m (15,780 ft), and Piz Bernina , at 4,049 m (13,284 ft). The second-highest major peaks are Monte Rosa , at 4,634 m (15,203 ft), and Ortler , at 3,905 m (12,810 ft), respectively. A series of lower mountain ranges run parallel to

5664-572: The current is in one direction, such as rivers. The longer flank of such ripples is on the upstream side of the current. Symmetric wave ripples occur in environments where currents reverse directions, such as tidal flats. Mudcracks are a bed form caused by the dehydration of sediment that occasionally comes above the water surface. Such structures are commonly found at tidal flats or point bars along rivers. Secondary sedimentary structures are those which formed after deposition. Such structures form by chemical, physical and biological processes within

5760-424: The dominant industry by the end of the century. The Winter Olympic Games have been hosted in the Swiss, French, Italian, Austrian and German Alps. As of 2010, the region is home to 14 million people and has 120 million annual visitors. The English word Alps comes from the Latin Alpes . The Latin word Alpes could possibly come from the adjective albus ("white"), or could possibly come from

5856-656: The dominant particle size. Most geologists use the Udden-Wentworth grain size scale and divide unconsolidated sediment into three fractions: gravel (>2 mm diameter), sand (1/16 to 2 mm diameter), and mud (<1/16 mm diameter). Mud is further divided into silt (1/16 to 1/256 mm diameter) and clay (<1/256 mm diameter). The classification of clastic sedimentary rocks parallels this scheme; conglomerates and breccias are made mostly of gravel, sandstones are made mostly of sand , and mudrocks are made mostly of mud. This tripartite subdivision

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5952-553: The end of the Mesozoic and continues into the present. The formation of the Alps was a segment of this orogenic process, caused by the collision between the African and the Eurasian plates that began in the late Cretaceous Period. Under extreme compressive stresses and pressure, marine sedimentary rocks were uplifted, forming characteristic recumbent folds , and thrust faults . As

6048-598: The end of the golden age of alpinism . Karl Blodig (1859–1956) was among the first to successfully climb all the major 4,000 m peaks. He completed his series of ascents in 1911. Many of the big Alpine three-thousanders were climbed in the early 19th century, notably the Grossglockner (1800) and the Ortler (1804), although some of them were climbed only much later, such at Mont Pelvoux (1848), Monte Viso (1861) and La Meije (1877). The first British Mont Blanc ascent by

6144-489: The field. Sedimentary structures can indicate something about the sedimentary environment or can serve to tell which side originally faced up where tectonics have tilted or overturned sedimentary layers. Sedimentary rocks are laid down in layers called beds or strata . A bed is defined as a layer of rock that has a uniform lithology and texture. Beds form by the deposition of layers of sediment on top of each other. The sequence of beds that characterizes sedimentary rocks

6240-404: The flow calms and the particles settle out of suspension . Most authors presently use the term "mudrock" to refer to all rocks composed dominantly of mud. Mudrocks can be divided into siltstones, composed dominantly of silt-sized particles; mudstones with subequal mixture of silt- and clay-sized particles; and claystones, composed mostly of clay-sized particles. Most authors use " shale " as

6336-485: The grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. The increased pressure and temperature stimulate further chemical reactions, such as the reactions by which organic material becomes lignite or coal. Lithification follows closely on compaction, as increased temperatures at depth hasten the precipitation of cement that binds the grains together. Pressure solution contributes to this process of cementation , as

6432-510: The grains, a lithic wacke would have abundant lithic grains and abundant muddy matrix, etc. Although the Dott classification scheme is widely used by sedimentologists, common names like greywacke , arkose , and quartz sandstone are still widely used by non-specialists and in popular literature. Mudrocks are sedimentary rocks composed of at least 50% silt- and clay-sized particles. These relatively fine-grained particles are commonly transported by turbulent flow in water or air, and deposited as

6528-587: The host rock. For example, a shell consisting of calcite can dissolve while a cement of silica then fills the cavity. In the same way, precipitating minerals can fill cavities formerly occupied by blood vessels , vascular tissue or other soft tissues. This preserves the form of the organism but changes the chemical composition, a process called permineralization . The most common minerals involved in permineralization are various forms of amorphous silica ( chalcedony , flint , chert ), carbonates (especially calcite), and pyrite . At high pressure and temperature,

6624-435: The lithologies dehydrates. Clay can be easily compressed as a result of dehydration, while sand retains the same volume and becomes relatively less dense. On the other hand, when the pore fluid pressure in a sand layer surpasses a critical point, the sand can break through overlying clay layers and flow through, forming discordant bodies of sedimentary rock called sedimentary dykes . The same process can form mud volcanoes on

6720-623: The main chain of the Alps, including the French Prealps in France and the Jura Mountains in Switzerland and France. The secondary chain of the Alps follows the watershed from the Mediterranean Sea to the Wienerwald , passing over many of the highest and most well-known peaks in the Alps. From the Colle di Cadibona to Col de Tende it runs westwards, before turning to the northwest and then, near

6816-450: The mineral dissolved from strained contact points is redeposited in the unstrained pore spaces. This further reduces porosity and makes the rock more compact and competent . Unroofing of buried sedimentary rock is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces the depth of burial, renewed exposure to meteoric water produces additional changes to the sedimentary rock, such as leaching of some of

6912-563: The more than 350 species recorded in the area. Rare species have included the first Austrian records of Pacific golden plover in 2008, semipalmated sandpiper in 2013 and blue-cheeked bee-eater in 2016. Some of the most sought after species for birdwatchers include great bustard , pygmy cormorant , ferruginous duck , little crake , European bee-eater and Syrian woodpecker . Notable plant species include Suaeda pannonica and Lepidium cartilagineum , as well as blue iris and Siberian iris . This Burgenland location article

7008-737: The mountains in which a valley leads from the plains and hilly pre-mountainous zones. In the medieval period hospices were established by religious orders at the summits of many of the main passes. The most important passes are the Col de l'Iseran (the highest), the Col Agnel , the Brenner Pass , the Mont-Cenis , the Great St. Bernard Pass , the Col de Tende , the Gotthard Pass , the Semmering Pass ,

7104-591: The national park is a meeting point for different plant and animal species. These include alpine, pannonian, asian, mediterranean and northern European species. This results in a mosaic of environments, including wetlands , herding meadows, meadows , sand steppes and salt areas. In the west the area is bordered by the Leitha Mountains , the Parndorf Plain in the north and the Hanság in the east. The mire of Hanság

7200-732: The orogenic events that affected them. The geological subdivision differentiates the Western, Eastern Alps, and Southern Alps: the Helveticum in the north, the Penninicum and Austroalpine system in the centre and, south of the Periadriatic Seam, the Southern Alpine system . According to geologist Stefan Schmid, because the Western Alps underwent a metamorphic event in the Cenozoic Era while

7296-438: The place of deposition. The nature of a sedimentary rock, therefore, not only depends on the sediment supply, but also on the sedimentary depositional environment in which it formed. As sediments accumulate in a depositional environment, older sediments are buried by younger sediments, and they undergo diagenesis. Diagenesis includes all the chemical, physical, and biological changes, exclusive of surface weathering, undergone by

7392-627: The processes responsible for their formation: clastic sedimentary rocks, biochemical (biogenic) sedimentary rocks, chemical sedimentary rocks, and a fourth category for "other" sedimentary rocks formed by impacts, volcanism , and other minor processes. Clastic sedimentary rocks are composed of rock fragments ( clasts ) that have been cemented together. The clasts are commonly individual grains of quartz , feldspar , clay minerals , or mica . However, any type of mineral may be present. Clasts may also be lithic fragments composed of more than one mineral. Clastic sedimentary rocks are subdivided according to

7488-607: The range's area), Italy (27.2%), France (21.4%), Switzerland (13.2%), Germany (5.8%), Slovenia (3.6%), Liechtenstein (0.08%) and Monaco (0.001%). The highest portion of the range is divided by the glacial trough of the Rhône valley, from Mont Blanc to the Matterhorn and Monte Rosa on the southern side, and the Bernese Alps on the northern. The peaks in the easterly portion of the range, in Austria and Slovenia, are smaller than those in

7584-480: The result of localized precipitation due to small differences in composition or porosity of the host rock, such as around fossils, inside burrows or around plant roots. In carbonate rocks such as limestone or chalk , chert or flint concretions are common, while terrestrial sandstones sometimes contain iron concretions. Calcite concretions in clay containing angular cavities or cracks are called septarian concretions . After deposition, physical processes can deform

7680-413: The rising peaks underwent erosion, a layer of marine flysch sediments was deposited in the foreland basin , and the sediments became involved in younger folds as the orogeny progressed. Coarse sediments from the continual uplift and erosion were later deposited in foreland areas north of the Alps. These regions in Switzerland and Bavaria are well-developed, containing classic examples of flysch , which

7776-454: The rock a grey or greenish colour. Iron(III) oxide (Fe 2 O 3 ) in a richer oxygen environment is often found in the form of the mineral hematite and gives the rock a reddish to brownish colour. In arid continental climates rocks are in direct contact with the atmosphere, and oxidation is an important process, giving the rock a red or orange colour. Thick sequences of red sedimentary rocks formed in arid climates are called red beds . However,

7872-511: The rock formations of the Alps in the 18th century. In the mid-19th century, the now-defunct idea of geosynclines was used to explain the presence of "folded" mountain chains. This theory was replaced in the mid-20th century by the theory of plate tectonics . The formation of the Alps (the Alpine orogeny ) was an episodic process that began about 300 million years ago. In the Paleozoic Era

7968-469: The same size, the rock is called 'well-sorted', and when there is a large spread in grain size, the rock is called 'poorly sorted'. The form of the clasts can reflect the origin of the rock. For example, coquina , a rock composed of clasts of broken shells, can only form in energetic water. The form of a clast can be described by using four parameters: Chemical sedimentary rocks have a non-clastic texture, consisting entirely of crystals. To describe such

8064-433: The sediment supply, caused, for example, by seasonal changes in rainfall, temperature or biochemical activity. Laminae that represent seasonal changes (similar to tree rings ) are called varves . Any sedimentary rock composed of millimeter or finer scale layers can be named with the general term laminite . When sedimentary rocks have no lamination at all, their structural character is called massive bedding. Graded bedding

8160-402: The sediment, producing a third class of secondary structures. Density contrasts between different sedimentary layers, such as between sand and clay, can result in flame structures or load casts , formed by inverted diapirism . While the clastic bed is still fluid, diapirism can cause a denser upper layer to sink into a lower layer. Sometimes, density contrasts occur or are enhanced when one of

8256-443: The sediment. They can be indicators of circumstances after deposition. Some can be used as way up criteria . Organic materials in a sediment can leave more traces than just fossils. Preserved tracks and burrows are examples of trace fossils (also called ichnofossils). Such traces are relatively rare. Most trace fossils are burrows of molluscs or arthropods . This burrowing is called bioturbation by sedimentologists. It can be

8352-453: The subsurface that is useful for civil engineering , for example in the construction of roads , houses , tunnels , canals or other structures. Sedimentary rocks are also important sources of natural resources including coal , fossil fuels , drinking water and ores . The study of the sequence of sedimentary rock strata is the main source for an understanding of the Earth's history , including palaeogeography , paleoclimatology and

8448-730: The summer months and where huts and hay barns can be found, sometimes constituting tiny hamlets. Therefore, the term "the Alps", as a reference to the mountains, is a misnomer. The term for the mountain peaks varies by nation and language: words such as Horn , Kogel , Kopf , Gipfel , Spitze , Stock , and Berg are used in German-speaking regions; Mont , Pic , Tête , Pointe , Dent , Roche , and Aiguille in French-speaking regions; and Monte , Picco , Corno , Punta , Pizzo , or Cima in Italian-speaking regions. The Alps are

8544-527: The three major types of rock, fossils are most commonly found in sedimentary rock. Unlike most igneous and metamorphic rocks, sedimentary rocks form at temperatures and pressures that do not destroy fossil remnants. Often these fossils may only be visible under magnification . Dead organisms in nature are usually quickly removed by scavengers , bacteria , rotting and erosion, but under exceptional circumstances, these natural processes are unable to take place, leading to fossilisation. The chance of fossilisation

8640-530: The various orogenies including exposures of basement rock. Due to the ever-present geologic instability, earthquakes continue in the Alps to this day. Typically, the largest earthquakes in the alps have been between magnitude 6 and 7 on the Richter scale. Geodetic measurements show ongoing topographic uplift at rates of up to about 2.5 mm per year in the North, Western and Central Alps, and at ~1 mm per year in

8736-532: The west in the Bernese Oberland. Because of his work he came to be known as the "father of the ice-age concept" although other naturalists before him put forth similar ideas. Agassiz studied glacier movement in the 1840s at the Unteraar Glacier where he found the glacier moved 100 m (328 ft) per year, more rapidly in the middle than at the edges. His work was continued by other scientists and now

8832-536: The western Mediterranean to Trieste on the Adriatic and Vienna at the beginning of the Pannonian Basin . The mountains were formed over tens of millions of years as the African and Eurasian tectonic plates collided. Extreme shortening caused by the event resulted in marine sedimentary rocks rising by thrusting and folding into high mountain peaks such as Mont Blanc and the Matterhorn . Mont Blanc spans

8928-404: The woody tissue of plants. Soft tissue has a much smaller chance of being fossilized, and the preservation of soft tissue of animals older than 40 million years is very rare. Imprints of organisms made while they were still alive are called trace fossils , examples of which are burrows , footprints , etc. As a part of a sedimentary rock, fossils undergo the same diagenetic processes as does

9024-451: Was for centuries a part of Lake Neusiedl . Lake Neusiedl itself is situated at the lowest point of the Little Hungarian Plain at an altitude of around 115m above sea level. The ownership structure of the national park Neusiedler See-Seewinkel is different from that of other national parks in Austria. Neusiedlersee-Seewinkel is not owned by any government but rather by around 1,200 different owners. Most of them are local farmers that receive

9120-470: Was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies ( marine snow ). Sedimentation may also occur as dissolved minerals precipitate from water solution . The sedimentary rock cover of the continents of the Earth's crust is extensive (73% of the Earth's current land surface), but sedimentary rock

9216-480: Was occasionally used as a name for Scotland , although it is more likely derived from the Latin word albus , the colour white. In modern languages the term alp , alm , albe or alpe refers to a grazing pastures in the alpine regions below the glaciers, not the peaks. An alp refers to a high mountain pasture, typically near or above the tree line , where cows and other livestock are taken to be grazed during

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