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Stalactites and Stalagmites
Stalactites and stalagmitesStalactites and stalagmites are formed by water dripping or flowing from fractures on the ceiling of a cave . They are the most common types of speleothems in caves. In caves, stalagmites grow rather slowly—0.00028–0.037 in/yr (0.007–0.929 mm/yr)—while in artificial tunnels and basements they grow much faster. Soda straw stalactites are the fastest growing (up to 1.57 in/yr, 40 mm/yr), but most fragile stalactites in caves. Soda straw stalactites form along a drop of water and continue growing down from the cave ceiling forming a tubular stalactite, which resembles a drinking straw in appearance. Their internal diameter is exactly equal to the diameter of the water drop. Formation of most stalactites is initiated as soda straws. If water flows on their external surface, they begin to grow in thickness and obtain a conical form. If a stalactite curves along its length, it is called a deflected stalactite. If its curving is known to be caused by air currents, it is called anemolite. Petal-shaped tubular stalactites composed of aragonite are called spathites. When some stalactites touch each other they form a drapery with a curtain-like appearance. When dripping water falls down on the floor of the cave it form stalagmites, which grow up vertically from the cave floor. Any changes in the direction of the growth axis of the stalagmite are suggestive of folding of the floor of the cave during the growth of the stalagmite. If a stalagmite is small, flat and round, it is called button stalagmite. Stalagmites resembling piled-up plates with broken borders are called pile-of-plates stalagmites. Rare varieties of stalagmites are mushroom stalagmites (partly composed of mud and having a mushroom shape), mud stalagmites (formed by mud) and lily pad stalagmites (resembling a lily pad on the surface of a pond). A calcite crust (shelfstone) grows around a stalagmite if it is flooded by a cave pool and forms a candlestick. When a stalactite touches a stalagmite it forms a column. Usually, stalactites and stalagmites in caves are formed by calcite, less frequently by aragonite, and rarely by gypsum . Fifty-four other cave minerals are known to form rare stalactites. Sometimes calcite stalactites or stalagmites are overgrown by aragonite crystals . This is due to precipitation of calcite that raises the ratio of magnesium to calcium in the solution enough that aragonite becomes stable. Rarely, elongated single crystals or twins of calcite are vertically oriented and look like stalactites, but in fact are not stalactites because they are not formed by dripping or flowing water and don't have hollow channels inside. These elongated crystals are formed from water films on their surface. In some volcanic lava tube caves exist lava stalactites and stalagmites that are not speleothems because they are not composed of secondary minerals . They are primary forms of the cooling, dripping lava. The internal structure of stalactites and stalagmites across their growth axis usually consists of concentric rings around the hollow channel. These rings contain different amounts of clay and other inclusions, and reflect drier and wetter periods. Clay rings reflect hiatuses of the growth of the sample. Stalagmites may be formed for periods ranging from a few hundreds years up to one million years. Stalactites and stalagmites in caves have such great variety of shapes, forms, and color that each of them is unique in appearance. At the same time, their growth rates are so slow that once broken, they cannot recover during a human life span of time. Thus, stalactites and stalagmites are considered natural heritage objects and are protected by law in most countries, and their collection, mining, and selling is prohibited. See also Cave minerals and speleothems |
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"Stalactites and Stalagmites." World of Earth Science. 2003. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "Stalactites and Stalagmites." World of Earth Science. 2003. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1G2-3437800579.html "Stalactites and Stalagmites." World of Earth Science. 2003. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1G2-3437800579.html |
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stalactites and stalagmites
stalactites and stalagmites Stalactites and stalagmites are secondary carbonate deposits found in caves in limestone areas. They can be classified together as speleothems (from the Greek words for ‘cave’ and ‘deposit’). Stalactites hang down from the ceilings of caves while stalagmites grow up from the floor. The majority of stalactites and stalagmites are composed of calcite (calcium carbonate), although in certain circumstances they may consist of other minerals, such as aragonite or gypsum. They are deposited from supersaturated waters and their formation is favoured during periods of relative warmth and wetness. Therefore, their rate of growth is controlled climatically. In addition to climatic controls, local chemical and hydrological factors may determine whether one individual speleothem grows faster or slower than another. Estimated rates of stalagmite growth range between 0.2 and 36 cm per 1000 years, while stalactites may grow significantly faster. Some stalactites and stalagmites contain annual bands, analogous to tree rings, which are in some cases visible to the naked eye and in others visible only under ultraviolet light. In the future, it may be possible to reconstruct interannual climate variations from stalactites and stalagmites in the same way that tree rings have been used. The age of stalactites and stalagmites can be determined precisely by measuring certain radioactive isotopes of uranium and thorium. When a stalactite or stalagmite is deposited it contains a large amount of uranium and no thorium because of differences in the chemical behaviour of these elements. Uranium decays radioactively to produce thorium-230 at a known rate. By measuring the amount of thorium-230 that has been produced relative to the amount of uranium, an age can be calculated. These ages have provided geologists with insights into climate change over the past 350 000 years (the limit of this dating technique), because periods when there was minimal formation of stalactites and stalagmites can be interpreted as being relatively cold and dry. Stalactites and stalagmites from caves which are now submerged beneath the sea demonstrate that sea levels have changed in the past. By dating such stalactites and stalagmites (which can form only when they are exposed by a fall in sea level), constraints can be placed on the extent and timing of these sea-level changes. Stalactites and stalagmites can also be used to provide constraints on rates of landscape evolution by dating valley incision or tectonic uplift. In addition, ages from stalactites and stalagmites associated with archaeological and palaeontological material from cave sites may provide valuable chronological control on that material. It may be possible to obtain further information about past climates by determining the ratios of different oxygen isotopes in the calcite. Although stalactites and stalagmites are scientifically valuable, it is also important to conserve them as they are an integral and beautiful component of the cave environment.
M. S. Roberts |
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PAUL HANCOCK and BRIAN J. SKINNER. "stalactites and stalagmites." The Oxford Companion to the Earth. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. PAUL HANCOCK and BRIAN J. SKINNER. "stalactites and stalagmites." The Oxford Companion to the Earth. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O112-stalactitesandstalagmites.html PAUL HANCOCK and BRIAN J. SKINNER. "stalactites and stalagmites." The Oxford Companion to the Earth. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O112-stalactitesandstalagmites.html |
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stalactite and stalagmite
stalactite and stalagmite , mineral forms often found in caves; sometimes collectively called dripstone. A stalactite is an icicle-shaped mass of calcite attached to the roof of a limestone cavern. Groundwater trickling through cracks in the roofs of such caverns contains dissolved calcium bicarbonate. When a drop of water comes in contact with the air of the cavern, some of the calcium bicarbonate is transformed into calcium carbonate, which is precipitated out of the water solution and forms a ring of calcite on the roof of the cavern. By repetition of this process the length and thickness of the stalactite is increased. A stalagmite is a cone of calcite rising from the floor of a cavern. Stalagmites and stalactites are often found in pairs, the stalagmite being formed as a result of further evaporation and precipitation from solution after the trickle of water falls from the stalactite. Stalactites and stalagmites often meet each other to form solid pillars. Curtains of dripstone sometimes form when water drips from the ceiling of a cave along joint planes. Since stalactites, stalagmites, and curtains of dripstone form only in the presence of air, their existence in a cave indicates that the cave was above the water table while the dripstone was forming. The many colors often seen in these formations are caused by the presence of impurities. Celebrated caverns that owe much of their beauty to their stalactites and stalagmites are Mammoth Cave, Ky.; the Luray Caverns, Va.; and the Carlsbad Caverns, N.Mex. Onyx marble (Mexican onyx, Egyptian alabaster, or Oriental alabaster), used as a decorative stone, is derived from stalagmites and stalactites, as well as from similar deposits. |
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"stalactite and stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalactite and stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-stalacti.html "stalactite and stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-stalacti.html |
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stalactite
stalactite icicle-like deposit of carbonate of lime pendent from a cave-roof. XVI. — modL. stalactītēs, f. Gr. stalaktós dropping, dripping, f. stalak-, base of stalássein drip, let drip; see -ITE.
So stalagmite similar deposit rising from the floor of a cave. XVIII. — modL. stalagmītēs, f. Gr. stálagma, stalagmós. |
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T. F. HOAD. "stalactite." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "stalactite." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-stalactite.html T. F. HOAD. "stalactite." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-stalactite.html |
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stalagmite
sta·lag·mite / stəˈlagˌmīt/ • n. a mound or tapering column rising from the floor of a cave, formed of calcium salts deposited by dripping water and often uniting with a stalactite. DERIVATIVES: stal·ag·mit·ic / ˌstaləgˈmitik/ adj. |
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"stalagmite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalagmite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-stalagmite.html "stalagmite." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-stalagmite.html |
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stalactite
sta·lac·tite / stəˈlakˌtīt/ • n. a tapering structure hanging like an icicle from the roof of a cave, formed of calcium salts deposited by dripping water. Compare with stalagmite. DERIVATIVES: sta·lac·tit·ic / ˌstaləkˈtitik/ adj. |
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"stalactite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalactite." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-stalactite.html "stalactite." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-stalactite.html |
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stalactite
stalactite.
1. System of corbelling, called muqarna, really brick squinches (see dome) and vaults with the soffits elaborately carved to resemble a series of stalactites, in Islamic, particularly Moorish, architecture. 2. Stone or stucco forms resembling stalactites or icicles, called congelation, found in grottoes. |
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JAMES STEVENS CURL. "stalactite." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. JAMES STEVENS CURL. "stalactite." A Dictionary of Architecture and Landscape Architecture. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O1-stalactite.html JAMES STEVENS CURL. "stalactite." A Dictionary of Architecture and Landscape Architecture. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O1-stalactite.html |
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stalactite
stalactite An elongated body of dripstone descending from the roof of a cave in a karst environment. It is produced by calcite precipitation as excess carbon dioxide diffuses into the air from water droplets entering a cave environment.
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MICHAEL ALLABY. "stalactite." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "stalactite." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-stalactite.html MICHAEL ALLABY. "stalactite." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-stalactite.html |
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stalagmite
stalagmite A pinnacle of dripstone rising from the floor of a cave in a karst environment. It is produced by the precipitation of calcite as excess carbon dioxide diffuses into the air when water droplets strike the floor.
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Cite this article
MICHAEL ALLABY. "stalagmite." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "stalagmite." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-stalagmite.html MICHAEL ALLABY. "stalagmite." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-stalagmite.html |
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stalactite
stalactite Elongated body of dripstone descending from the roof of a cave in a karst environment. It is produced by calcite precipitation as excess carbon dioxide diffuses from water droplets entering a cave environment.
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AILSA ALLABY and MICHAEL ALLABY. "stalactite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "stalactite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-stalactite.html AILSA ALLABY and MICHAEL ALLABY. "stalactite." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-stalactite.html |
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stalagmite
stalagmite Pinnacle of dripstone rising from the floor of a cave in a karst environment. It is produced by the precipitation of calcite as excess carbon dioxide diffuses when water droplets strike the floor.
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Cite this article
AILSA ALLABY and MICHAEL ALLABY. "stalagmite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "stalagmite." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-stalagmite.html AILSA ALLABY and MICHAEL ALLABY. "stalagmite." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-stalagmite.html |
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stalactite
stalactite Icicle-like formation of calcium carbonate found hanging from the roofs of caves. It is made by the precipitation of limestone from water that seeps into limestone caves.
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"stalactite." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalactite." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-stalactite.html "stalactite." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-stalactite.html |
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stalagmite
stalagmite Deposit of crystalline calcium carbonate rising from the floor of a cavern, and formed by dripping water that seeps into limestone caves.
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"stalagmite." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalagmite." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-stalagmite.html "stalagmite." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-stalagmite.html |
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stalagmite
stalagmite see stalactite and stalagmite . |
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Cite this article
"stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-X-stalagmi.html "stalagmite." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-stalagmi.html |
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stalactite
stalactite
•calcite • campsite
•website • dacite • insight
•Monophysite • magnesite • eyesight
•hindsight • bombsight • foresight
•bauxite • quartzite • leucocyte
•Hussite • gunsight • phagocyte
•marcasite • parasite • anthracite
•oversight • worksite
•bipartite, multipartite, partite, quadripartite, sexpartite, tripartite
•transvestite • airtight • Hittite
•magnetite • appetite • stalactite
•watertight • Levite • Muscovite
•Hepplewhite • bobwhite
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"stalactite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalactite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-stalactite.html "stalactite." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-stalactite.html |
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stalagmite
stalagmite
•Hamite, samite
•marmite • Semite • Vegemite
•eremite • Hashemite • Fatimite
•chromite • Edomite • sodomite
•stalagmite • Elamite • dolomite
•Adullamite • dynamite • catamite
•Benthamite
•termite, thermite
•Samnite • sennight • midnight
•lignite • selenite • gelignite
•kaolinite • Leninite
•finite, transfinite
•watchnight • fortnight • Sunnite
•exurbanite, suburbanite, urbanite
•manganite • ammonite • Mennonite
•Canaanite • Maronite • bentonite
•Irvingite • respite • alexandrite
•Arkwright • cartwright • nephrite
•playwright • wainwright
•wheelwright • millwright
•shipwright • copyright • Nazirite
•pyrite • eyebright • nitrite • contrite
•chlorite • forthright • downright
•Fulbright • upright • meteorite
•diorite • fluorite
•Labourite (US Laborite) • sybarite
•Thatcherite • phosphorite • azurite
•anchorite • Hitlerite • dolerite
•Amorite • Minorite • laterite
•Hutterite • birthright
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Cite this article
"stalagmite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "stalagmite." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-stalagmite.html "stalagmite." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-stalagmite.html |
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