Rimstone called gours, is a type of speleothem in the form of a stone dam. Rimstone is made up of other minerals that build up in cave pools; the formation created, which looks like stairs extends into flowstone above or below the original rimstone. Rimstone is covered with small, micro-gours on horizontal surfaces. Rimstone basins may form terraces that extend over hundreds of feet, with single basins known up to 200 feet long from Tham Xe Biang Fai in Laos Rimstone dams form where there is some gradient, hence flow, over the edge of a pool. Crystallization begins to occur at the air/water/rock interface; the turbulence caused by flow over the edge of the building dam may contribute to the outgassing or loss of carbon dioxide from water, result in precipitation of mineral on this edge. When dams form under running water, they tend to be higher. Shallow-gradient dams tend to be more sinuous in nature. Rimstone is one of the most common cave formations, after flowstone and stalagmites. Rimstone or gours can be formed by the secondary deposits derived from lime or mortar.
These secondary deposits consisting of calcium carbonate, are called calthemites and mimics the shapes and forms of cave speleothems to create stalactites, stalagmites and gours. Gours form beneath concrete structures on a floor with a gradual sloping surface or on the side of rounded stalagmites derived from concrete. Most of the calcium carbonate carried by the leachate is deposited as stalactites, leaving little in solution to be carried to the ground to create stalagmites and gours; the leachate which does reach the ground evaporates due to air movement beneath the concrete structure, hence micro-gours are more common. The secondary deposits derived from concrete are the result of concrete degradation, where calcium ions are leached out of the concrete in solution and redeposited on the underside of a concrete structure. Calcium carbonate deposition as micro-gours occur when the solution drops to the ground under the concrete structure. Carbon dioxide is absorbed into the alkaline leachate solution, which facilitates the chemical reactions to precipitate any calcium carbonate remaining in solution as a stalagmite and micro-gours.
This chemical reaction creating calthemites, is different from that which creates speleothems in limestone caves. Secondary deposits, which create stalagmites, flowstone, rimstone etc, outside the natural cave environment, are referred to as “calthemites”; these concrete derived secondary deposits can’t be referred to as “speleothems” due to the definition of the word. The Virtual Cave's page on Rimstone
Boxwork is an uncommon type of mineral structure, or speleogen found in caves and erosive environments. According to KellerLynn, "Boxwork is a speleogen, forming when bedrock between preexisting calcite veins were preferentially weathered away as the cave developed."Boxwork is composed of thin blades of the mineral calcite that project from cave walls or ceilings that intersect one another at various angles, forming a box-like or honeycomb pattern. The boxwork fins once filled cracks in the rock; as the walls of the cave began to dissolve away, the more resistant vein and crack fillings did not, or at least dissolved at a slower rate than the surrounding rock, leaving the calcite fins projecting from the cave surfaces. Some of the most extensive boxwork deposits in the world are found in Wind Cave, Wind Cave National Park in South Dakota, USA. Other outstanding examples occur in Cody Caves, Cody Caves Provincial Park in British Columbia, Canada. Boxwork can be seen at Jewel Cave National Monument, at Innerspace Caverns near Georgetown, Texas.
Wind Cave National Park: Origin of Boxwork The Virtual Cave's page on boxwork
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines connecting a common point, the apex, to all of the points on a base, in a plane that does not contain the apex. Depending on the author, the base may be restricted to be a circle, any one-dimensional quadratic form in the plane, any closed one-dimensional figure, or any of the above plus all the enclosed points. If the enclosed points are included in the base, the cone is a solid object. In the case of a solid object, the boundary formed by these lines or partial lines is called the lateral surface. In the case of line segments, the cone does not extend beyond the base, while in the case of half-lines, it extends infinitely far. In the case of lines, the cone extends infinitely far in both directions from the apex, in which case it is sometimes called a double cone. Either half of a double cone on one side of the apex is called a nappe.
The axis of a cone is the straight line, passing through the apex, about which the base has a circular symmetry. In common usage in elementary geometry, cones are assumed to be right circular, where circular means that the base is a circle and right means that the axis passes through the centre of the base at right angles to its plane. If the cone is right circular the intersection of a plane with the lateral surface is a conic section. In general, the base may be any shape and the apex may lie anywhere. Contrasted with right cones are oblique cones, in which the axis passes through the centre of the base non-perpendicularly. A cone with a polygonal base is called a pyramid. Depending on the context, "cone" may mean a convex cone or a projective cone. Cones can be generalized to higher dimensions; the perimeter of the base of a cone is called the "directrix", each of the line segments between the directrix and apex is a "generatrix" or "generating line" of the lateral surface. The "base radius" of a circular cone is the radius of its base.
The aperture of a right circular cone is the maximum angle between two generatrix lines. A cone with a region including its apex cut off by a plane is called a "truncated cone". An "elliptical cone" is a cone with an elliptical base. A "generalized cone" is the surface created by the set of lines passing through a vertex and every point on a boundary; the volume V of any conic solid is one third of the product of the area of the base A B and the height h V = 1 3 A B h. In modern mathematics, this formula can be computed using calculus – it is, up to scaling, the integral ∫ x 2 d x = 1 3 x 3. Without using calculus, the formula can be proven by comparing the cone to a pyramid and applying Cavalieri's principle – comparing the cone to a right square pyramid, which forms one third of a cube; this formula cannot be proven without using such infinitesimal arguments – unlike the 2-dimensional formulae for polyhedral area, though similar to the area of the circle – and hence admitted less rigorous proofs before the advent of calculus, with the ancient Greeks using the method of exhaustion.
This is the content of Hilbert's third problem – more not all polyhedral pyramids are scissors congruent, thus volume cannot be computed purely by using a decomposition argument. The center of mass of a conic solid of uniform density lies one-quarter of the way from the center of the base to the vertex, on the straight line joining the two. For a circular cone with radius r and height h, the base is a circle of area π r 2 and so the formula for volume becomes V = 1 3 π r 2 h; the slant height of a right circular cone is the distance from any point on the circle of its base to the apex via a line segment along the surface of the cone. It is given by r 2 + h 2, where r is the radius of the base and h is the height; this can be proved by the Pythagorean theorem. The lateral surface area of a right circular cone is L S A = π r l where r is the radius of the circle at the bottom of the cone and l is the slant height of the cone; the surface area of the bottom c
Caves of Nerja
The Caves of Nerja are a series of caverns close to the town of Nerja in the Province of Málaga, Spain. Stretching for 5 kilometres, the caverns are one of Spain's major tourist attractions. Concerts are held in one of the chambers, which forms a natural amphitheatre; the caves were re-discovered in modern times on 12 January 1959 by five friends, who entered through a narrow sinkhole known as "La Mina". This forms one of the two natural entrances to the cave system. A third entrance was created in 1960 to allow easy access for tourists; the cave is divided into two main parts known as Nerja I and Nerja II. Nerja I includes the Show Galleries which are open to the public, with easy access via a flight of stairs and concreted pathways to allow tourists to move about in the cavern without difficulty. Nerja II, not open to the public, comprises the Upper Gallery discovered in 1960 and the New Gallery discovered in 1969. In February 2012 it was announced that Neanderthal cave paintings dated in 42,000 years have been discovered in the Caves of Nerja.
5 million years ago, during the Upper Miocene, water penetrated the fissures of the marble rock and dissolved it, forming a huge subterranean cavern. Seismic movement and landslides during the Holocene forced the water to find new pathways through the cave system and began the formation of the giant stalactites and stalagmites that can be seen in the cave. Skeletal remains found in the caverns indicate that they were inhabited from about 25,000 BC up until the Bronze Age. Cave paintings from the Paleolithic and post-Paleolithic eras have been discovered on the walls of the cave. For about 4,000 years from 25,000 BC the caves were used seasonally by a small group of humans, were occupied by cave hyena during the periods that the humans were absent. By 21,000 BC the human population had taken up year-round residence in the caves and had increased in number. A culture based on hunting in the local area had evolved, illustrated by first cave paintings found in the cave which date to around the time.
Pine nuts and snails were important elements of the diet. Up until around 10,800 BC the hunting culture continued to develop with more prey species being taken, including goats, rabbits and marine mammals. A wide variety of animal bones and fish bones from this time have been found in the cave, including the remains of a number of offshore species, along with stone and bone tools. By 4500 BC domesticated animals were being kept and the area around the cave was being used for farming and the production of pottery. By 3800 BC textiles and more advanced styles of pottery were being produced and parts of the cave were being used as a burial chamber; each of the galleries has a number of halls, areas where the walls, floors or ceilings close in to subdivide the main caverns. The Show Gallery is accessed by an 8 m flight of stairs leading to the Entrance Hall where archaeological excavations took place and where some of the finds are now displayed. Off to one side a passage leads the Mine Hall, Hall of the Sink where further archaeological excavations take place.
This area is not open to the public. Back through the Entrance Hall is the Hall of the Nativity, filled with columns of calcite. A skeleton recovered from the cave is on display in a glass case in this subsection. From the Entrance Hall a passage called the Hall of the Tusk leads down to the Hall of the Waterfall or Ballet, it is here that concerts and festivals of dance are staged and there are about 100 seats set permanently in the cave. This large cavern has little to separate it from the Hall of the Phantoms apart from some columns; the Hall of the Phantoms is named after an unusual speleothem. At the end of this cavern is a large rockfall which separates it from the Hall of the Cataclysm, over 100 m long and dominated by the huge central column, the biggest in the world, measuring 13 m by 7 m at the base and standing 32 m high. Further down into the hall is the Organ Corner where fluted columns can be struck to produce different notes; some of the columns seem to have been intentionally altered to produce different notes by the prehistoric inhabitants of the cave.
High up in the far corner of this cave is the opening which allows access to the Upper and New Galleries. The Upper and New Galleries are each divided into two halls. In the Upper Hall are the Columns of Hercules and the Hall of Immensity, while in the New Gallery there are the Hall of the Lance and the Hall of the Mountain; these two areas contain many of the cave paintings, but tourist access is restricted to specialised caving "speleothem tourism". Several expeditions have been made to know the cavity and its different galleries. In 1969 a narrow passage was discovered in the hall del Cataclismo; this step led to a magnificent find, the so-called high galleries and the new galleries, whose spectacular formations and prehistoric remains, can not yet be contemplated by the visitor. Throughout all these years, the Fundación Cueva de Nerja has promoted the study and research of the Cave, constituting the Scientific Committee formed by geologists, archaeologists, etc. making congresses, photographic studies, improvements in equipment and cultural activities.
In 2012 some organic remains associated with paintings of seals have been dated in 42 000 years which could be the first known work of art in the history of humanity. They could be the oldest paintings of humanity, po
Biospeleology known as cave biology, is a branch of biology dedicated to the study of organisms that live in caves and are collectively referred to as troglofauna. The first documented mention of a cave organisms dates back to 1689, with the documentation of the olm, a cave salamander. Discovered in a cave in Slovenia, in the region of Carniola, it was mistaken for a baby dragon and was recorded by Johann Weikhard von Valvasor in his work The Glory of the Duchy of Carniola; the first formal study on cave organisms was conducted on the blind cave beetle. Found in 1831 by Luka Čeč, an assistant to the lamplighter, when exploring the newly discovered inner portions of the Postojna cave system in southwestern Slovenia; the specimen was turned over to Ferdinand J. Schmidt, who described it in the paper Illyrisches Blatt, he named it Leptodirus Hochenwartii after the donor, gave it the Slovene name drobnovratnik and the German name Enghalskäfer, both meaning "slender-necked". The article represents the first formal description of a cave animal.
Subsequent research by Schmidt revealed further unknown cave inhabitants, which aroused considerable interest among natural historians. For this reason, the discovery of L. hochenwartii is considered as the starting point of biospeleology as a scientific discipline. Biospeleology was formalized as a science in 1907 by Emil Racoviţă with his seminal work Essai sur les problèmes biospéologiques. Cave organisms fall into three basic classes: Troglobites are obligatory cavernicoles, specialized for cave life; some can leave caves for short periods, may complete parts of their life cycles above ground, but cannot live their entire lives outside of a cave environment. Examples include chemotrophic bacteria, some species of flatworms and cavefish. Troglophiles can live part or all of their lives in caves, but can complete a life cycle in appropriate environments on the surface. Examples include cave crickets, millipedes and spiders. Trogloxenes frequent caves, may require caves for a portion of its life cycle, but must return to the surface for at least some portion of its life.
Oilbirds and the Daddy longlegs are trogloxenes Cave environments fall into three general categories: Endogean environments are the parts of caves that are in communication with surface soils through cracks and rock seams, groundwater seepage, root protrusion. Parahypogean environments are the threshold regions near cave mouths that extend to the last penetration of sunlight. Hypogean or "true" cave environments; these can be in regular contact with the surface via wind and underground rivers, or the migration of animals, or can be entirely isolated. Deep hypogean environments can host autonomous ecologies whose primary source of energy is not sunlight, but chemical energy liberated from limestone and other minerals by chemoautotrophic bacteria. Emil Racoviță Carl Eigenmann Louis Fage René Jeannel Curt Kosswig Bernard Collignon, scientific approaches. Edisud 1988 Fabien Steak, Approach biospéologie, File EFS Instruction No. 116, 1st Edition, 1997 C. Delamare-Debouteville, Life in caves, PUF, Que sais-je?, Paris 1971 Bernard Gèze, Scientific caving, Paris, 1965, p. 137-167 R. and V. Decou Ginet, Introduction to biology and groundwater ecology, University Publishing Delarge 1977 René Jeannel, Animal cave in France, Paris, 1926 René Jeannel, Living fossils caves, Paris, 1943 Edward Alfred Martel, Groundwater evolution, Paris, 1908, p. 242-289 Georges Émile Racovitza, Essay on biospéologiques problems, I Biospeologica 1907 Michel Siffre, Animals sinkholes and caves, Hachette, 1979 Michel Siffre, France The caves and caverns, ed. Privat, 1999, p. 136-153 G. and R. Thines Tercafs, Atlas of the underground life: the cave animals, Boubée and De Visscher, 1972 Albert Vandel Biospéologie: the biology of cave animals, Gauthier-Villars, Paris, 1964 Armand Vire, The subterranean fauna of France, Paris, 1900 Biospeleology.
A ponor is a natural opening where surface water enters into underground passages. The word derives from the proto-Slavic nora; the word "ponor" itself comes from Slovene. Whereas a sinkhole is a depression of surface topography with a pit or cavity directly underneath, a ponor is kind of a portal where a surface stream or lake flows either or underground into a karst groundwater system. Steady water erosion may have formed or enlarged the portal in rock, in a conglomerate, or in looser materials. Ponors are found only in karst regions; the entire Adriatic watershed within Bosnia and Herzegovina sits on Dinaric karst, with numerous explored and many more unexplored ponors and underground flows. There are several places in southeast Europe with the name "Ponor" due to associated karst openings. There are significant geological ponors in the Carpathian Mountains, the Dinaric Alps, Greece and parts of the southern United States. Karst spring Losing stream
A pit cave, shaft cave or vertical cave—or simply called a pit or pot. Pit caves form in limestone as a result of long-term erosion by water, they found deep within horizontal caves. Among cavers, a pit is a vertical drop of any depth that cannot be negotiated safely without the use of ropes or ladders. Exploration into pit caves requires the use of equipment such as nylon kernmantle rope or cable ladders. More specialized caving techniques such as the single rope technique are common practice and the preferred method of pit exploration for cavers worldwide; the SRT involves the use of 9–11 mm nylon static rope and mechanical descenders/ascenders. Vertical caving is a specialized sport that should be undertaken only after acquiring knowledge of, expertise in, proper vertical caving equipment and its use. For obvious reasons, vertical caving is more dangerous than "horizontal caving". Vertical caving requires the intimate understanding of ropes, anchors, rappelling devices and ascending systems.
Veteran cavers are knowledgeable in self rescue techniques including change-overs and pick-offs. Pit caving was pioneered by the British geologist John Beaumont who gave an account of his descent into Lamb Leer Cavern to the Royal Society in 1681. French caver Édouard-Alfred Martel first achieved the descent and exploration of the Gouffre de Padirac, France, as early as 1889 and the first complete descent of a 110 m wet vertical shaft at Gaping Gill, in Yorkshire, England, in 1895, he developed his own techniques using metallic ladders. In the 1930s, as caving became popular in France, several clubs in the Alps developed vertical cave exploration into a recognized outdoor sport. During World War II, a team composed by Pierre Chevalier, Fernand Petzl, Charles Petit-Didier and others explored the Dent de Crolles cave system near Grenoble, France, it became known as the deepest cave in the world at that time. The lack of available technical equipment during the war forced Chevalier and his team to innovate and develop their own.
The scaling-pole, nylon ropes, use of explosives in caves, mechanical rope-ascenders can be traced to the exploration of the Dent de Crolles cave system. In the late 1950s, American caver Bill Cuddington, known as "Vertical Bill", developed the single rope technique in the United States. In 1958, two Swiss alpinists and Marti teamed up, creating the first rope ascender, known as the Jumar. In 1968, Bruno Dressler asked Petzl, who worked as a metals machinist, to build a rope-ascending tool, today known as the Petzl Croll, which he had developed by adapting the Jumar to the specificity of pit caving. Pursuing these developments, in the 1970s Fernand Petzl started a small caving equipment manufacturing company, Petzl. Today it is a world leader in equipment for caving, at-height safety in civil engineering; the development of the rappel rack and the evolution of mechanical ascension systems, notably helped extend the practice and safety of pit exploration to a larger practice by established cavers.
The deepest individual pitch within a cave is 603 m in Vrtoglavica Cave in Slovenia. The second deepest pitch is Patkov Gušt at 553 m in Croatia. Lamb Leer, England, was entered by a 25 m pitch as early as the 17th century. Hranice Abyss, Czech Republic, is the deepest underwater cave in the world, the lowest confirmed depth is 473 m, the expected depth is 700–800 m. Pozzo del Merro, Italy, is the world's second deepest underwater pit cave, the deepest part reached is 392 m. El Capitan Pit, Prince of Wales Island, Alaska, USA, at 598.3 ft is the deepest vertical shaft in the United States. Fantastic Pit, Ellisons Cave System, Georgia, USA, at 586 ft is the deepest freefall pit in the lower 48 United States. Stupendous Pit, Rumbling Falls Cave, Tennessee, USA, is a 202 ft pit that drops into a 26 acres chamber. Hellhole, West Virginia, USA, has a 154 ft entrance drop and was the site of development of the single rope technique in the 1950s and'60s. Natural Trap Cave, located in the Bighorn Mountains of Wyoming, is 85 ft deep and home to one of the largest fossil finds in North America.
Sótano de Las Golondrinas, San Luis Potosí, Mexico, at 1,094 ft, is the deepest known freefall drop in the western hemisphere. Cenote Poza El Zacatón, Mexico, is the world's deepest cenote at 339 m CCTV announced that in Shaanxi Province 49 pit caves have been found; the largest one is 500 m in diameter. The caves are in pristine condition, they lie in mountains. The local governments are taking steps to preserve them in their natural state. A UNESCO survey found rare animals living in the entrances to the caves. Cenotes and Blue holes Pitch List of sinkholes Pit crater