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Dent Blanche Nappe
The Dent Blanche nappe or Dent Blanche klippe is a geologic nappe and klippe that crops out in the Pennine Alps. The nappe is tectonostratigraphically on top of the Penninic nappes and by most researchers seen as Austroalpine. The nappe is named after the mountain Dent Blanche, which is formed by rocks of the nappe. The most famous outcrop of the nappe is the Matterhorn, which is made of an erosional remnant (klippe) of Dent Blanche material lying on top of Penninic ophiolites ( Zermatt-Saas zone). Because of this the rock at the top of the Matterhorn ''came from Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...,'' as the Austroalpine nappes are fragments of the African Plate. References Geology of the Alps Structural geology Geology of Switzerland {{struc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology. It is integrated with Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface and the processes that have shaped that structure. Geologists study the mineralogical composition of rocks in order to get insight into their history of formation. Geology determines the relative ages of rocks found at a given location; geochemistry (a branch of geology) determines their absolute ages. By combining various petrological, crystallographic, and paleontological tools, geologists are able to chronicle the geological history of the Earth as a whole. One aspect is to demonstrate the age of the Earth. Geology provides evidence for plate tectonics, the ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matterhorn
The , ; ; ; or ; ; . is a mountain of the Alps, straddling the Main chain of the Alps, main watershed and border between Italy and Switzerland. It is a large, near-symmetric pyramidal peak in the extended Monte Rosa area of the Pennine Alps, whose summit is above sea level, making it List of Alpine four-thousanders, one of the highest summits in the Alps and Europe.Considering summits with at least 300 metres prominence, it is the 6th highest in the Alps and Europe outside the Caucasus Mountains. The four steep faces, rising above the surrounding glaciers, face the four compass points and are split by the ''Hörnli'', ''Furggen'', ''Leone''/''Lion'', and ''Zmutt'' ridges. The mountain overlooks the Swiss town of Zermatt, in the canton of Valais, to the northeast; and the Italian town of Breuil-Cervinia in the Aosta Valley to the south. Just east of the Matterhorn is Theodul Pass, the main passage between the two valleys on its north and south sides, which has been a trade rou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of The Alps
The Alps form part of a Cenozoic orogenic belt of mountain chains, called the Alpide belt, that stretches through southern Europe and Asia from the Atlantic all the way to the Himalayas. This belt of mountain chains was formed during the Alpine orogeny. A gap in these mountain chains in central Europe separates the Alps from the Carpathians to the east. Orogeny took place continuously and tectonic subsidence has produced the gaps in between. The Alps arose as a result of the collision of the African and Eurasian tectonic plates, in which the Alpine Tethys, which was formerly in between these continents, disappeared. Enormous stress was exerted on sediments of the Alpine Tethys basin and its Mesozoic and early Cenozoic strata were pushed against the stable Eurasian landmass by the northward-moving African landmass. Most of this occurred during the Oligocene and Miocene epochs. The pressure formed great recumbent folds, or ''nappes'', that rose out of what had been the Alpine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zermatt-Saas Zone
The Zermatt-Saas zone is a tectonic unit in the western part of the Alps. Its lithology is mainly ophiolite but there are some pelitic zones too. The Zermatt-Saas zone is tectonostratigraphically the highest part of the Penninic nappes and lies directly under the Sesia zone and Dent Blanche klippe, that are interpreted as belonging to the Austroalpine nappes. It lies on top of other Penninic nappes, as the Monte Rosa nappe or the Combin zone. The ophiolites of the Zermatt-Saas zone are mostly ultramafic rocks with greenschist facies mineralogy: serpentinites. Some mafic parts exist, they also have greenschist assemblages of actinolite, plagioclase and sometimes epidote or clinozoisite. However, relicts are found of blueschist and eclogite facies metamorphism during the Eocene, which shows that the current greenschist assemblage of the Zermatt-Saas zone is a retrograde Retrograde may refer to: Film and television * Retrograde (2004 film), ''Retrograde'' (2004 film), a film b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiolite
An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle (Earth), upper mantle that has been uplifted and exposed, and often emplaced onto continental crustal rocks. The Greek word ὄφις, ''ophis'' (''snake'') is found in the name of ophiolites, because of the superficial texture of some of them. Serpentinite especially evokes a snakeskin. (The suffix ''-lite'' is from the Greek ''lithos'', meaning "stone".) Some ophiolites have a green color. The origin of these rocks, present in many mountainous massifs, remained uncertain until the advent of plate tectonic theory. Their great significance relates to their occurrence within mountain belts such as the Alps and the Himalayas, where they document the existence of former ocean basins that have now been consumed by subduction. This insight was one of the founding pillars of plate tectonics, and ophiolites have always played a central role in plate tectonic theory and the interpretation of ancient mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, transports it to another location where it is deposit (geology), deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by Solvation, dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and Wind wave, waves; glacier, glacial Plucking (glaciation), plucking, Abrasion (geology), abrasion, and scour; areal flooding; Aeolian processes, wind abrasion; groundwater processes; and Mass wastin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dent Blanche
The Dent Blanche is a mountain in the Pennine Alps, lying in the canton of Valais in Switzerland. At -high, it is one of the highest peaks in the Alps. Naming The original name was probably ''Dent d'Hérens'', the current name of the nearby Dent d'Hérens which does not overlook the Val d'Hérens. The nearby north face of the Dent d'Hérens is glaciated while the Dent Blanche holds much less snow, it was even called ''Dent Noire'' (''Black Tooth'') on the Woerl Atlas of 1842. In fact on older maps, in the area where both summits lie, only the name ''Weisszahnhorn'' (from German: ''White Tooth Peak'') was given, the French name (''Dent Blanche'') only appearing in 1820. Because cartographers usually made their observations far from the mountainous remote areas and also because the Dent d'Hérens is sometime hidden behind the Dent Blanche thus less visible, the latter received the name. The inhabitants of the lower Val d'Hérens called the current Dent d'Hérens, ''Dent Blanche'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nappe
In geology, a nappe or thrust sheet is a large sheetlike body of rock that has been moved more than or above a thrust fault from its original position. Nappes form in compressional tectonic settings like continental collision zones or on the overriding plate in active subduction zones. Nappes form when a mass of rock is forced (or "thrust") over another rock mass, typically on a low angle fault plane. The resulting structure may include large-scale recumbent folds, shearing along the fault plane,Twiss, Robert J. and Eldridge M. Moores, ''Structural Geology,'' W. H. Freeman, 1992, p. 236 imbricate thrust stacks, fensters and klippes. The term stems from the French word for ''tablecloth'' in allusion to a rumpled tablecloth being pushed across a table. History Nappes or nappe belts are a major feature of the European Alps, Dinarides, Carpathians and Balkans. Since the 19th century many geologists have uncovered areas with large-scale overthrusts. Some of these were su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austroalpine Nappes
The Austroalpine nappes are a geological nappe stack system in the European Alps. They structurally on top of the Penninic (meaning they were thrust over them). The prefix Austro in this term refers to Austria, rather than south/southern. This is because the bulk of the Austroalpine nappes (which constitute the Eastern Alps except for some tectonic windows) is in Austria, although they also reach into Eastern Switzerland. The western boundary of the Eastern Alps is the Lake Constance - Chur – Lake Como line. Geographic position and nappes in the Western Alps The Austroalpine nappes constitute the Eastern Alps, except for some tectonic windows such as the Tauern window, the Rechnitz window (both in Austria) and the Engadin window (Switzerland). They cover eastern Switzerland and the largest part Austria. In the Western Alps the Sesia (Italy) and the Dent Blanche (Switzerland) units form a klippe over the Penninic nappes. They have been labelled as Austroalpine becaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penninic Nappes
The Penninic nappes or the Penninicum, commonly abbreviated as Penninic, are one of three nappe stacks and geological zones in which the Alps can be divided. In the western Alps the Penninic nappes are more obviously present than in the eastern Alps (in Austria), where they crop out as a narrow band. The name ''Penninic'' is derived from the Pennine Alps, an area in which rocks from the Penninic nappes are abundant. Of the three nappe stacks the Penninic nappes have the highest metamorphic grade. They contain high grade metamorphic rocks of different paleogeographic origins. They were deposited as sediments on the crust that existed between the European and Apulian plates before the Alps were formed. They are characteristically ophiolite sequences and deep marine sediments, metamorphosed to phyllites, schists and amphibolites. Middle Penninic nappes include the Monte Rosa, Mont Fort, Siviez-Mischabel, Cimes Blanches and Frilihorn, of European origin. Upper Penninic nappes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
