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Crevasse
A crevasse is a deep crack that forms in a glacier or ice sheet. Crevasses form as a result of the movement and resulting stress associated with the shear stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement. The resulting intensity of the shear stress causes a breakage along the faces. Description Crevasses often have vertical or near-vertical walls, which can then melt and create seracs, arches, and other ice formations. These walls sometimes expose layers that represent the glacier's stratigraphy. Crevasse size often depends upon the amount of liquid water present in the glacier. A crevasse may be as deep as and as wide as The presence of water in a crevasse can significantly increase its penetration. Water-filled crevasses may reach the bottom of glaciers or ice sheets and provide a direct hydrologic connection between the surface, where significant summer melting occurs, and the bed of the glacier, where additional wate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levee Breach
A levee breach or levee failure (also known as dyke breach or dyke failure) is a situation where a levee (or dyke) fails or is intentionally breached, causing the previously contained water to flood the land behind the levee. Causes Man-made levees can fail in a number of ways. The most frequent (and dangerous) form of levee failure is a ''breach''. A ''levee breach'' is when part of the levee actually breaks away, leaving a large opening for water to flood the land protected by the levee. Foundation failure A breach can be a sudden or gradual failure that is caused either by surface erosion or by a subsurface failure of the levee. Levee breaches are often accompanied by levee boils, or sand boils. The underseepage resurfaces on the landside, in the form of a volcano-like cone of sand. Boils signal a condition of incipient instability which may lead to erosion of the levee toe or foundation or result in sinking of the levee into the liquefied foundation below. Some engineer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildspitze Seen From Hinterer Brunnkogel, With Marked Ascent Track Of Ski Mountaineer
Wildspitze () is the highest mountain in the Ötztal Alps and in North Tyrol, as well as the second highest mountain in Austria after the Großglockner and in terms of prominence (2261 m) is the fourth summit of the Alps and the fifteenth of Europe. Location The Wildspitze is on a ridge called ''Weißkamm'' ("white ridge") that joins the main chain of the Alps at the Weißkugel. Its north and west flanks form the end of the Pitz valley, while the south and east flanks rise above the upper ends of the Ötztal. The mountain has twin peaks, with a rocky south summit (3768 m or by most other sources 3770 mThe Austrian Alpine Club's Alpine Club map of the Ötztal AlpsWalter Klier, ''Ötztaler Alpen: ein Führer für Täler, Hütten und Berge'', Rother, Munich, 14th print, 2006.) and a firn-covered north summit at about 3760 m. Bergsteiger, January 2001, page 25. Richard Goedeke: ''3000er in den Nordalpen.'', Bruckmann Verlag, Munich, 2004, , page 93. The mountain is surrounded by glac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographical Terminology In Mountaineering
Geography (from Ancient Greek ; combining 'Earth' and 'write', literally 'Earth writing') is the study of the lands, features, inhabitants, and phenomena of Earth. Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be. While geography is specific to Earth, many concepts can be applied more broadly to other celestial bodies in the field of planetary science. Geography has been called "a bridge between natural science and social science disciplines." Origins of many of the concepts in geography can be traced to Greek Eratosthenes of Cyrene, who may have coined the term "geographia" (). The first recorded use of the word γεωγραφία was as the title of a book by Greek scholar Claudius Ptolemy (100 – 170 AD). This work created the so-called "Ptolemaic tradition" of geography, which included "Ptolemaic cartographic theory." ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Landforms
Glacial landforms are landforms created by the action of glaciers. Most of today's glacial landforms were created by the movement of large ice sheets during the Quaternary glaciations. Some areas, like Fennoscandia and the southern Andes, have extensive occurrences of glacial landforms; other areas, such as the Sahara, display rare and very old fossil glacial landforms. Erosional landforms As the glaciers expand, due to their accumulating weight of snow and ice they crush, abrade, ''and'' scour surfaces such as rocks and bedrock. The resulting erosional landforms include striations, cirques, glacial horns, arêtes, trim lines, U-shaped valleys, roches moutonnées, overdeepenings and hanging valleys. * Striations: grooves and indentations in rock outcrops, formed by the scraping of small sediments on the bottom of a glacier across the Earth's surface. The direction of striations display the direction the glacier was moving. * Cirque: Starting location for mountain gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaciology
Glaciology (; ) is the scientific study of glaciers, or, more generally, ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, climatology, meteorology, hydrology, biology, and ecology. The impact of glaciers on people includes the fields of human geography and anthropology. The discoveries of water ice on the Moon, Mars, Europa (moon), Europa and Pluto add an extraterrestrial component to the field, which is referred to as "astroglaciology". Overview A glacier is a persistent body of dense ice, a form of rock) formed from snow falling and accumulating over a long period of time; glaciers move very slowly, either descending from high mountains, as in valley glaciers, or moving outward from centers of accumulation, as in continental glaciers. Areas of study within glaciology include glacial history and the reconstruction of past glaciation. A glaciologist is a person ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Friction Hitch Knots
A list is a Set (mathematics), set of discrete items of information collected and set forth in some format for utility, entertainment, or other purposes. A list may be memorialized in any number of ways, including existing only in the mind of the list-maker, but lists are frequently written down on paper, or maintained electronically. Lists are "most frequently a tool", and "one does not ''read'' but only ''uses'' a list: one looks up the relevant information in it, but usually does not need to deal with it as a whole".Lucie Doležalová,The Potential and Limitations of Studying Lists, in Lucie Doležalová, ed., ''The Charm of a List: From the Sumerians to Computerised Data Processing'' (2009). Purpose It has been observed that, with a few exceptions, "the scholarship on lists remains fragmented". David Wallechinsky, a co-author of ''The Book of Lists'', described the attraction of lists as being "because we live in an era of overstimulation, especially in terms of information, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rope Team
A rope team (sometimes also called moving together) is a climbing technique where two or more climbers who are attached to a single climbing rope move simultaneously together along easy-angled terrain that does not require points of fixed climbing protection to be inserted along the route. Rope teams contrast with simul-climbing, which involves only two climbers and where they are ascending steep terrain that will require many points of protection to be inserted along the route. A specific variant of a rope team is the technique of , which is used by mountain guides to help weaker clients, and which also does not employ fixed climbing protection points. Rope teams are commonly used in alpine climbing, particularly for moving across glaciers and traveling along snow slopes and ridges. Members are typically spaced apart with any surplus rope coiled and carried by the first and last members. The weaker members of the team are placed in the middle, however, it is important that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Freedom Of The Hills
''Mountaineering: The Freedom of the Hills'' is often considered the standard textbook for mountaineering and climbing in North America. The book was first published in 1960 by The Mountaineers of Seattle, Washington. The book was written by a team of over 40 experts in the field. Development The book grew out of the annual climbing course run since 1935 by the Mountaineers, for which the reading material was originally a combination of European works and lecturers' mimeo outlines. These were assembled into the ''Climber's Notebook'' and published by the Mountaineers as the hardbound ''Mountaineers Handbook'' in 1948. By 1955 the rapid postwar evolution of climbing techniques and tools had made the ''Handbook'' out of date, and the effort was begun to produce ''Freedom of the Hills''. Nearly 80 major contributors are credited in the first edition and it was organized by a committee of 8 editors. The first four editions were only available in hardcover. The title of the boo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snow Bridge
A snow bridge is an arc formed by snow across a crevasse, a crack in rock, a creek, or some other opening in terrain. It is typically formed by snow drift, which first creates a cornice, which may then grow to reach the other side of the opening. Dangers A snow bridge may completely cover the opening and thus present a danger by creating an illusion of unbroken surface under which the opening is concealed by an unknown thickness of snow, possibly only a few centimetres. Snow bridges may also form inside a crevasse, making it appear shallow. A snow bridge is thicker and stronger at the edge of a crevasse; therefore, a fall through a bridge usually happens at some distance from the edge.''Mountain Operations'' (September 1947) United States War Department Field Manual FM-10,p. 204/ref> See also *Ice bridge An ice bridge is a frozen natural structure formed over seas, bays, rivers or lake surfaces. They facilitate migration of animals or people over a water body that wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
