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Glaciofluvial Sediments
Glaciofluvial deposits or Glacio-fluvial sediments consist of boulders, gravel, sand, silt and clay from ice sheets or glaciers. They are transported, sorted and deposited by streams of water. The deposits are formed beside, below or downstream from the ice. They include kames, kame terraces and eskers formed in ice contact and outwash fans and outwash plains below the ice margin. Typically the outwash sediment is carried by fast and turbulent fluvio-glacial meltwater streams, but occasionally it is carried by catastrophic outburst floods. Larger elements such as boulders and gravel are deposited nearer to the ice margin, while finer elements are carried farther, sometimes into lakes or the ocean. The sediments are sorted by fluvial processes. They differ from glacial till, which is moved and deposited by the ice of the glacier, and is unsorted. Ice-contact deposits A subglacial megaflood may cut cavities into the base of the ice. As the flood dies down, sediment is depos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20190622 Thorsmork 7743 (48459729752)
Nineteen or 19 may refer to: * 19 (number), the natural number following 18 and preceding 20 * one of the years 19 BC, AD 19, 1919, 2019 Films * ''19'' (film), a 2001 Japanese film * ''Nineteen'' (film), a 1987 science fiction film Music * 19 (band), a Japanese pop music duo Albums * ''19'' (Adele album), 2008 * ''19'', a 2003 album by Alsou * ''19'', a 2006 album by Evan Yo * ''19'', a 2018 album by MHD * ''19'', one half of the double album ''63/19'' by Kool A.D. * ''Number Nineteen'', a 1971 album by American jazz pianist Mal Waldron * ''XIX'' (EP), a 2019 EP by 1the9 Songs * "19" (song), a 1985 song by British musician Paul Hardcastle. * "Nineteen", a song by Bad4Good from the 1992 album '' Refugee'' * "Nineteen", a song by Karma to Burn from the 2001 album ''Almost Heathen''. * "Nineteen" (song), a 2007 song by American singer Billy Ray Cyrus. * "Nineteen", a song by Tegan and Sara from the 2007 album '' The Con''. * "XIX" (song), a 2014 song by Slipknot. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Till
image:Geschiebemergel.JPG, Closeup of glacial till. Note that the larger grains (pebbles and gravel) in the till are completely surrounded by the matrix of finer material (silt and sand), and this characteristic, known as ''matrix support'', is diagnostic of till. image:Glacial till exposed in roadcut-750px.jpg, Glacial till with tufts of grass Till or glacial till is unsorted glacier, glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes. Description Till is a form of '' glacial drift'', which is rock material transported by a glacier and deposited directly from the ice or from running water emerging from the ice. It is distinguished from other forms of drift in that it is depos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baltoro Glacier - Braldu River
Baltoro may refer to: *Baltoro Glacier, a glacier in the Karakoram mountain range northern Pakistan. ''Baltoro'' as single expression without adjunct usually refers to this glacier. *Baltoro Muztagh Baltoro may refer to: *Baltoro Glacier, a glacier in the Karakoram mountain range northern Pakistan. ''Baltoro'' as single expression without adjunct usually refers to this glacier. * Baltoro Muztagh, a mountain range in the Karakoram mountain rang ..., a mountain range in the Karakoram mountain range in northern Pakistan and northwestern China, north and east of the Baltoro glacier. * Baltoro Kangri, a mountain in the Karakoram mountain range (however not in the Baltoro Muztagh), at the source of the Baltoro Glacier. {{geodis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jökulhlaup
A jökulhlaup ( ) (literally "glacial run") is a type of glacial outburst flood. It is an Icelandic term that has been adopted in glaciological terminology in many languages. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland, which are triggered by geothermal heating and occasionally by a volcanic subglacial eruption, but it is now used to describe any large and abrupt release of water from a subglacial or proglacial lake/reservoir. Since jökulhlaups emerge from hydrostatically sealed lakes with floating levels far above the threshold, their peak discharge can be much larger than that of a marginal or extra-marginal lake burst. The hydrograph of a jökulhlaup from Vatnajökull typically either climbs over a period of weeks with the largest flow near the end, or it climbs much faster during the course of some hours. These patterns are suggested to reflect channel melting, and sheet flow under the front, respectively. Similar pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abrasion (geology)
Abrasion is a process of erosion which occurs when material being transported wears away at a surface over time. It is the process of friction caused by scuffing, scratching, wearing down, marring, and rubbing away of materials. The intensity of abrasion depends on the hardness, concentration, velocity and mass of the moving particles. Abrasion generally occurs in four ways: glaciation slowly grinds rocks picked up by ice against rock surfaces; solid objects transported in river channels make abrasive surface contact with the bed and walls; objects transported in waves breaking on coastlines; and by wind transporting sand or small stones against surface rocks. Abrasion, under its strictest definition, is commonly confused with attrition and sometimes hydraulic action however, the latter less commonly so. Both abrasion and attrition refers to the wearing down of an object. Abrasion occurs as a result of two surfaces rubbing against each other, resulting in the wearing down of one o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavitation
Cavitation is a phenomenon in which the static pressure of a liquid reduces to below the liquid's vapour pressure, leading to the formation of small vapor-filled cavities in the liquid. When subjected to higher pressure, these cavities, called "bubbles" or "voids", collapse and can generate shock waves that may damage machinery. These shock waves are strong when they are very close to the imploded bubble, but rapidly weaken as they propagate away from the implosion. Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic stress through repeated implosion. This results in surface fatigue of the metal causing a type of wear also called "cavitation". The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Action
Hydraulic action, most generally, is the ability of moving water (flowing or waves) to dislodge and transport rock particles. This includes a number of specific erosional processes, including abrasion, at facilitated erosion, such as ''static erosion'' where water leaches salts and floats off organic material from unconsolidated sediments, and from ''chemical erosion'' more often called chemical weathering. It is a mechanical process, in which the moving water current flows against the banks and bed of a river, thereby removing rock particles. A primary example of hydraulic action is a wave striking a cliff face which compresses the air in cracks of the rocks. This exerts pressure on the surrounding rock which can progressively crack, break, splinter and detach rock particles. This is followed by the decompression of the air as the wave retreats which can occur suddenly with explosive force which additionally weakens the rock. Cracks are gradually widened so each wave compresses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacier Mouth
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as crevasses and seracs, as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques, moraines, or fjords. Although a glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets (also known as "continental glaciers") in the polar regions, but glaciers may be found in mountain ranges on every continent other than the Australian mainland, including Oceania's high-latitude oceanic island countries such as New Zealand. Between latitudes 35°N and 35°S, glaciers occur only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamicton
Diamicton (also diamict) (from Greek ''δια'' (dia-): through and ''µεικτός'' (meiktós): mixed) is a terrigenous sediment (a sediment resulting from dry-land erosion) that is unsorted to poorly sorted and contains particles ranging in size from clay to boulders, suspended in an unconsolidated matrix of mud or sand. Today, the word has strong connotations to glaciation but can be used in a variety of geological settings.Jackson, J.A., J. Mehl, and K. Neuendorf (2005) ''Glossary of Geology'' American Geological Institute, Alexandria, Virginia. 800 pp. Bennett, M.R., and N.F. Glasser (2009) ''Glacial Geology: Ice Sheets and Landforms'', 2nd Ed. John Wiley & Sons, Ltd., New York, New York. 400 pp. Tucker, M.E. (2003) ''Sedimentary Rocks in the Field'' John Wiley & Sons, Ltd., New York, New York. 244 pp. The term was proposed by Flint and othersFlint, R.F., J.E. Sanders, and J. Rodgers (1960) ''Diamictite, a substitute term for symmictite'' Geological Society of America Bullet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek grc, label=none, πλεῖστος, pleīstos, most and grc, label=none, καινός, kainós (latinized as ), 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by the Isthmus of Panama, causing Great American Interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moulin (geomorphology)
A moulin (or glacier mill) is a roughly circular, vertical (or nearly vertical) well-like shaft formed where a surface meltstream exploits a weakness in the ice. The term is derived from the French word for mill.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. They can be up to 10 meters wide and are typically found on ice sheets and flat areas of a glacier in a region of transverse crevasses. Moulins can reach the bottom of the glacier, hundreds of meters deep, or may only reach the depth of common crevasse formation (about 10–40 m) where the stream flows englacially. They are the most typical cause for the formation of a glacier cave. Moulins are parts of the internal structure of glaciers, that carry meltwater from the surface down to wherever it may go. Water from a moulin often exits the glacier at base level, sometimes into the sea, and occa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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