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21-759: The Widderstein is a massif in the mountains around the valley of Kleinwalsertal , which runs past it to the north. To the northeast of the Großer Widderstein, separated by the Karlstor (2,100 m), is the Kleiner Widderstein (2,236 m). To the east the valley of Gemsteltal divides the flanks of the Widderstein from the massif around the Elferkopf (2,387 m) and the Walser Geißhorn (2,366 m). To

42-572: A Widerstein Sp. . According to this the name means "Stein der Widder" ("Stone of the Widder"), a Widder being an ibex or a male sheep . The first recorded ascent of the Großer Widderstein took place on 25 July 1669 (1664 according to other sources) by a Reverend Bickel from Schröcken. The normal route to the top begins at the Hochtannberg Pass and runs across meadow slopes initially heading towards

63-465: A large mountain mass or compact group of connected mountains forming an independent portion of a range. The Face on Mars is an example of an extraterrestrial massif. Massifs may also form underwater, as with the Atlantis Massif . Crust (geology) In geology , the crust is the outermost solid shell of a planet , dwarf planet , or natural satellite . It is usually distinguished from

84-524: Is a planet's "original" crust. It forms from solidification of a magma ocean. Toward the end of planetary accretion , the terrestrial planets likely had surfaces that were magma oceans. As these cooled, they solidified into crust. This crust was likely destroyed by large impacts and re-formed many times as the Era of Heavy Bombardment drew to a close. The nature of primary crust is still debated: its chemical, mineralogic, and physical properties are unknown, as are

105-407: Is a principal mountain mass, such as a compact portion of a mountain range , containing one or more summits (e.g. France's Massif Central ). In mountaineering literature, a massif is frequently used to denote the main mass of an individual mountain. As a purely scientific term in geology , however, a "massif" is separately and more specifically defined as a section of a planet's crust that

126-491: Is debated. The anorthosite highlands of the Moon are primary crust, formed as plagioclase crystallized out of the Moon's initial magma ocean and floated to the top; however, it is unlikely that Earth followed a similar pattern, as the Moon was a water-less system and Earth had water. The Martian meteorite ALH84001 might represent primary crust of Mars; however, again, this is debated. Like Earth, Venus lacks primary crust, as

147-402: Is demarcated by faults or flexures . In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole. A massif is a smaller structural unit than a tectonic plate and is considered the fourth-largest driving force in geomorphology . The word "massif" originates from French (in which the word also means "massive"), where it is used to refer to

168-490: Is needed to create tertiary crust, and Earth is the only planet in the Solar System with plate tectonics. Earth's crust is a thin shell on the outside of Earth, accounting for less than 1% of Earth's volume. It is the top component of the lithosphere , a division of Earth's layers that includes the crust and the upper part of the mantle . The lithosphere is broken into tectonic plates that move, allowing heat to escape from

189-533: The Widderstein Hut . At a height of about 2,000 m a path forks off to the west that leads in just under 15 minutes to the rock massif of the Widderstein. From here a waymarked rock path ( UIAA grade I) runs through a rockfall endangered gully to the summit ridge and from there eastwards to the summit cross . The approach to this mountain path may be made from Baad, Austria in the Kleinwalsertal via

210-469: The adiabatic rise of mantle causes partial melting. Tertiary crust is more chemically-modified than either primary or secondary. It can form in several ways: The only known example of tertiary crust is the continental crust of the Earth. It is unknown whether other terrestrial planets can be said to have tertiary crust, though the evidence so far suggests that they do not. This is likely because plate tectonics

231-458: The East Arête is grade IV. The southwest face to the southwest summit (III-IV) was first climbed in 1951 by B. Segger and F. Hieber. The first ascent of the west face of the south shoulder (V+) was made in 1935 by Helmreich and Hutter. The south arête (II-III, one spot IV) was first negotiated by W. Blenk in the descent. Massif A massif ( / m æ ˈ s iː f , ˈ m æ s ɪ f / )

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252-698: The Hochalp Pass or from Bödmen through the Gemstelbach valley, through the Obere Gemstelalpe (1,694 m) via the Gemstel Pass to the Widderstein Hut. There are several climbing routes on the faces of the Widderstein. On the north face is a grade IV+ route. conquered by E. König and R. Schmierle in 1897. The North Pinnacle ( Nordpfeiler ) is classed as grade III/ IV (length of rope in the lower section),

273-423: The crust ranges between about 20 and 120 km. Crust on the far side of the Moon averages about 12 km thicker than that on the near side . Estimates of average thickness fall in the range from about 50 to 60 km. Most of this plagioclase-rich crust formed shortly after formation of the Moon, between about 4.5 and 4.3 billion years ago. Perhaps 10% or less of the crust consists of igneous rock added after

294-453: The entire planet has been repeatedly resurfaced and modified. Secondary crust is formed by partial melting of mostly silicate materials in the mantle, and so is usually basaltic in composition. This is the most common type of crust in the Solar System. Most of the surfaces of Mercury, Venus, Earth, and Mars comprise secondary crust, as do the lunar maria . On Earth secondary crust forms primarily at mid-ocean spreading centers , where

315-463: The formation of the initial plagioclase-rich material. The best-characterized and most voluminous of these later additions are the mare basalts formed between about 3.9 and 3.2 billion years ago. Minor volcanism continued after 3.2 billion years, perhaps as recently as 1 billion years ago. There is no evidence of plate tectonics . Study of the Moon has established that a crust can form on a rocky planetary body significantly smaller than Earth. Although

336-491: The igneous mechanisms that formed them. This is because it is difficult to study: none of Earth's primary crust has survived to today. Earth's high rates of erosion and crustal recycling from plate tectonics has destroyed all rocks older than about 4 billion years , including whatever primary crust Earth once had. However, geologists can glean information about primary crust by studying it on other terrestrial planets. Mercury's highlands might represent primary crust, though this

357-416: The interior of Earth into space. A theoretical protoplanet named " Theia " is thought to have collided with the forming Earth, and part of the material ejected into space by the collision accreted to form the Moon. As the Moon formed, the outer part of it is thought to have been molten, a " lunar magma ocean ". Plagioclase feldspar crystallized in large amounts from this magma ocean and floated toward

378-796: The mountain. The summit block of the Großer Widderstein consists of main dolomite of the Lech valley formation ( Lechtaldecke ), which here has been pushed up over the Allgäu formation ( Allgäudecke ). To the northwest in the area of the Hochalpsees there are Kössen beds ( Kössener Schichten ). The Großer Widderstein is mentioned for the first time in 1059 in a document belonging to the Bishopric of Augsburg : in Widerostein . Other records appears in 1471 and 1485 as Widerstain . Blasius Hueber's 1783 map of Vorarlberg shows

399-634: The south is the Hochtann Mountain Pass (1,676 m), where the Allgäu Alps give way to the Lechquellen Mountains . To the west lies the valley of Bärgunttal and the massif around the Heiterberg (2,188 m). In a hollow to the northwest below the side of the summit lies the lake of Hochalpsee (1,970 m). The boundary between the municipalities of Warth and Mittelberg runs over

420-444: The surface. The cumulate rocks form much of the crust. The upper part of the crust probably averages about 88% plagioclase (near the lower limit of 90% defined for anorthosite ): the lower part of the crust may contain a higher percentage of ferromagnesian minerals such as the pyroxenes and olivine , but even that lower part probably averages about 78% plagioclase. The underlying mantle is denser and olivine-rich. The thickness of

441-792: The underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be distinguished based on its phase (solid crust vs. liquid mantle). The crusts of Earth , Mercury , Venus , Mars , Io , the Moon and other planetary bodies formed via igneous processes and were later modified by erosion , impact cratering , volcanism, and sedimentation. Most terrestrial planets have fairly uniform crusts. Earth, however, has two distinct types: continental crust and oceanic crust . These two types have different chemical compositions and physical properties and were formed by different geological processes. Planetary geologists divide crust into three categories based on how and when it formed. This

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