|
Cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as ''speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caving
Caving – also known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland – is the recreational pastime of exploring wild cave systems (as distinguished from show caves). In contrast, speleology is the scientific study of caves and the cave environment.Caving in New Zealand (from Te Ara: The Encyclopedia of New Zealand, Accessed 2012-11.) The challenges involved in caving vary according to the cave being visited; in addition to the total absence of light beyond the entrance, negotiating pitches, squeezes, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Cave
A sea cave, also known as a littoral cave, is a type of cave formed primarily by the wave action of the sea. The primary process involved is erosion. Sea caves are found throughout the world, actively forming along present coastlines and as relict sea caves on former coastlines. Some of the largest wave-cut caves in the world are found on the coast of Norway, but are now 100 feet or more above present sea level. These would still be classified as littoral caves. By contrast, in places like Thailand's Phang Nga Bay, solutionally formed caves in limestone have been flooded by the rising sea and are now subject to littoral erosion, representing a new phase of their enlargement. Some of the best-known sea caves are European. Fingal's Cave, on the island of Staffa in Scotland, is a spacious cave some 70 m long, formed in columnar basalt. The Blue Grotto of Capri, although smaller, is famous for the apparent luminescent quality of its water, imparted by light passing through underwate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleology
Speleology is the scientific study of caves and other karst features, as well as their make-up, structure, physical properties, history, life forms, and the processes by which they form ( speleogenesis) and change over time (speleomorphology). The term ''speleology'' is also sometimes applied to the recreational activity of exploring caves, but this is more properly known as ''caving'', ''potholing'' (British English), or ''spelunking''. Speleology and caving are often connected, as the physical skills required for ''in situ'' study are the same. Speleology is a cross-disciplinary field that combines the knowledge of chemistry, biology, geology, physics, meteorology, and cartography to develop portraits of caves as complex, evolving systems. History Before modern speleology developed, John Beaumont wrote detailed descriptions of some Mendip caves in the 1680s. The term speleology was coined by Émile Rivière in 1890. Prior to the mid-nineteenth century the scientific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lechuguilla Cave
At , Lechuguilla Cave is the eighth-longest explored cave in the world and the second deepest () in the continental United States. It is most famous for its unusual geology, rare formations, and pristine condition. The cave is named for the canyon through which it is entered, which is named for ''Agave lechuguilla'', a species of plant found there. Lechuguilla is in Carlsbad Caverns National Park, New Mexico. Access to the cave is limited to approved scientific researchers, survey and exploration teams, and National Park Service management-related trips. Exploration history Lechuguilla Cave was known until 1986 as a small, insignificant historic site in the park's back country. Small amounts of bat guano were mined from the entrance passages for a year under a mining claim filed in 1914. The historic cave contained a entrance pit known as Misery Hole, which led to of dry, dead-end passages. The cave was visited infrequently after mining activities ceased. However, in the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stalactite
A stalactite (, ; from the Greek 'stalaktos' ('dripping') via ''stalassein'' ('to drip') is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble and that can be deposited as a colloid, or is in suspension, or is capable of being melted, may form a stalactite. Stalactites may be composed of lava, minerals, mud, peat, pitch, sand, sinter, and amberat (crystallized urine of pack rats). A stalactite is not necessarily a speleothem, though speleothems are the most common form of stalactite because of the abundance of limestone caves. The corresponding formation on the floor of the cave is known as a stalagmite. Mnemonics have been developed for which word refers to which type of formation; one is that ''stalactite'' has a C for "ceiling", and ''stalagmite'' has a G for "ground". Another example is that ''stalactites'' "hang on ''T''ight" and ''stalagmites'' "''M''ight gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speleothem
A speleothem (; ) is a geological formation by mineral deposits that accumulate over time in natural caves. Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take a variety of forms, depending on their depositional history and environment. Their chemical composition, gradual growth, and preservation in caves make them useful paleoclimatic proxies. Chemical and physical characteristics More than 300 variations of cave mineral deposits have been identified. The vast majority of speleothems are calcareous, composed of calcium carbonate (CaCO3) minerals ( calcite or aragonite). Less commonly, speleothems are made of calcium sulfate ( gypsum or mirabilite) or opal. Speleothems of pure calcium carbonate or calcium sulfate are translucent and colorless. The presence of iron oxide or copper provides a reddish brown color. The presence of manganese oxide can create darker colors such as black or dark brown. Speleothems can also be br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinkhole
A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openings where surface water enters into underground passages known as ''ponor'', swallow hole or swallet. A '' cenote'' is a type of sinkhole that exposes groundwater underneath. A ''sink'' or ''stream sink'' are more general terms for sites that drain surface water, possibly by infiltration into sediment or crumbled rock. Most sinkholes are caused by karst processes – the chemical dissolution of carbonate rocks, collapse or suffosion processes. Sinkholes are usually circular and vary in size from tens to hundreds of meters both in diameter and depth, and vary in form from soil-lined bowls to bedrock-edged chasms. Sinkholes may form gradually or suddenly, and are found worldwide. Formation Natural processes Sinkholes may capture su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stalagmite
A stalagmite (, ; from the Greek , from , "dropping, trickling") is a type of rock formation that rises from the floor of a cave due to the accumulation of material deposited on the floor from ceiling drippings. Stalagmites are typically composed of calcium carbonate, but may consist of lava, mud, peat, pitch, sand, sinter, and amberat (crystallized urine of pack rats). The corresponding formation hanging down from the ceiling of a cave is a stalactite. Mnemonics have been developed for which word refers to which type of formation; one is that ''stalactite'' has a C for "ceiling", and ''stalagmite'' has a G for "ground", another is that, as with ants in the pants, the mites go up and the tights (tites) come down. Formation and type Limestone stalagmites The most common stalagmites are speleothems, which usually form in limestone caves. Stalagmite formation occurs only under certain pH conditions within the cavern. They form through deposition of calcium c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karst
Karst is a topography formed from the dissolution of soluble rocks such as limestone, Dolomite (rock), dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant rocks, such as quartzite, given the right conditions. Subterranean drainage may limit surface water, with few to no rivers or lakes. However, in regions where the dissolved bedrock is covered (perhaps by debris) or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground. The study of ''paleokarst'' (buried karst in the stratigraphic column) is important in petroleum geology because as much as 50% of the world's hydrocarbon reserves are hosted in carbonate rock, and much of this is found in porous karst systems. Etymology The English word ''karst'' was borrowed from German language, German in the late 19th century, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helictite
A helictite is a speleothem (cave-formed mineral) found in a limestone cave that changes its axis from the vertical at one or more stages during its growth. Helictites have a curving or angular form that looks as if they were grown in zero gravity. They are most likely the result of capillary forces acting on tiny water droplets, a force often strong enough at this scale to defy gravity. Helictites are, perhaps, the most delicate of cave formations. They are usually made of needle-form calcite and aragonite. Helictite forms have been described in several types: ribbon helictites, saws, rods, butterflies, "hands", curly-fries, and "clumps of worms". They typically have radial symmetry. They can be easily crushed or broken by the slightest touch. Because of this, helictites are rarely seen within arm's reach in tourist caves. Timpanogos Cave National Monument in Utah has one of the largest collections of these formations in the world. Large numbers are also in the Jenolan Cav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flowstone
Flowstones are sheetlike deposits of calcite or other carbonate minerals, formed where water flows down the walls or along the floors of a cave. They are typically found in "solution caves", in limestone, where they are the most common speleothem. However, they may form in any type of cave where water enters that has picked up dissolved minerals. Flowstones are formed via the degassing of vadose percolation waters. Flowstone may also form on manmade structures as a result of calcium hydroxide being leached from concrete, lime or mortar. These secondary deposits created outside the cave environment, which mimic the shapes and forms of speleothems, are classified as "calthemites" and are associated with concrete degradation.Smith, G.K., (2016). “Calcite Straw Stalactites Growing From Concrete Structures”, Cave and Karst Science, Vol.43, No.1, P.4-10, (April 2016), British Cave Research Association, ISSN 1356-191X. Formation Flowing films of water that move along floors or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soda Straw
A soda straw (or simply straw) is a speleothem in the form of a hollow mineral cylinder (geometry), cylindrical tube. They are also known as tubular stalactites. Soda straws grow in places where water leaches slowly through cracks in rock, such as on the roofs of caves. Soda straws in caves rarely grow more than a few millimetres per year and may average one tenth of a millimetre per year.Hill, C A, and Forti, P, (1997). "Speleothem Growth Rates", Cave Minerals of the World, (2nd edition). [Huntsville, Alabama: National Speleological Society Inc.] pp 285 - 287 A soda straw can turn into a stalactite if the hole at the bottom is blocked, or if the water begins flowing on the outside surface of the hollow tube. Soda straws can also form outside the cave environment on exposed concrete surfaces as a type of calthemite, growing significantly faster than those formed on rock. Formation These tubes form when calcium carbonate or calcium sulfate dissolved in the water comes out of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Sinkhole")
.jpg "Click for more on -> Karst")
