Hranice Abyss
Hranice Abyss ( cs, Hranická propast) is the deepest flooded pit cave in the world. It is a karst sinkhole near the town of Hranice, Czech Republic. The greatest confirmed depth is , of which is underwater. In 2020, a scientific expedition to the cave revealed that part of the system apparently reaches 1 kilometre deep, albeit with the lowest reaches sediment-filled. Analysis of the water found carbon and helium isotopes which implied that the cave has been formed by acidic waters, heated by the mantle, welling up from below. Description It is located near the Zbrašov Aragonite Caves, which are open to the public. The total depth of the abyss (at least 473.5 m) is unknown, as the lower part of the abyss is flooded by the Hranice Lake. The abyss has an elliptical shape and is situated in the SE-SW direction. It is approximately 110 metres long at its longest point and 50 metres wide at its widest point. For most visitors the most interesting figure is the depth of the abyss ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Pit Cave
A pit cave, shaft cave or vertical cave—or often simply called a pit (in the US) and pothole or pot (in the UK); jama in South Slavic languages scientific and colloquial vocabulary (borrowed since early research in the Western Balkan Dinaric Alpine karst)—is a type of cave which contains one or more significant vertical shafts rather than being predominantly a conventional horizontal cave passage. Pit caves typically form in limestone as a result of long-term erosion by water. They can be open to the surface or 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. Pit caving Techniques Exploration into pit caves ("vertical caving", also called "potholing" in the UK and "pit caving" in US English) requires the use of equipment such as nylon kernmantle rope or cable ladders. The specialized caving techniques of single rope technique (SRT) is common practice and the preferre ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Karst
Karst is a topography formed from the dissolution of soluble rocks such as limestone, 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 in the late 19th century, which entered German much earlier ... [...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 surf ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Hranice (Přerov District)
Hranice (; german: Weißkirchen or ''Mährisch Weißkirchen'') is a town in Přerov District in the Olomouc Region of the Czech Republic. It has about 17,000 inhabitants. The historic town centre is well preserved and is protected by law as an urban monument zone. The town is known for the Hranice Abyss. Administrative parts Hranice is made up of nine town parts and villages: *Hranice I-Město *Hranice II-Lhotka *Hranice III-Velká *Hranice IV-Drahotuše *Hranice V-Rybáře *Hranice VI-Valšovice *Hranice VII-Slavíč *Hranice VIII-Středolesí *Hranice IX-Uhřínov Středolesí and Uhřínov form an exclave of the municipal territory. Etymology The name Hranice literally means "border". It is sometimes called ''Hranice na Moravě'' ("Hranice in Moravia") to distinguish from other places with the same name. Geography Hranice is located about northeast of Přerov and east of Olomouc. It lies mostly in the Moravian Gate lowland. The exclave of the municipal territory lies alr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Karst
Karst is a topography formed from the dissolution of soluble rocks such as limestone, 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 in the late 19th century, which entered German much earlier ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Czech Academy Of Sciences
The Czech Academy of Sciences (abbr. CAS, cs, Akademie věd České republiky, abbr. AV ČR) was established in 1992 by the Czech National Council as the Czech successor of the former Czechoslovak Academy of Sciences and its tradition goes back to the Royal Bohemian Society of Sciences (founded in 1784) and the Emperor Franz Joseph Czech Academy for Sciences, Literature and Arts (founded in 1890). The Academy is the leading non-university public research institution in the Czech Republic. It conducts both fundamental and strategic applied research. It has three scientific divisions, namely the Division of Mathematics, Physics, and Earth Sciences, Division of Chemical and Life Sciences, and Division of Humanities and Social Sciences. The Academy currently manages a network of sixty research institutes and five supporting units staffed by a total of 6,400 employees, over one half of whom are university-trained researchers and Ph.D. scientists. The Head Office of the Academy and ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Krzysztof Starnawski
Krzysztof Starnawski (born 1968) is a Polish technical and cave diver and International Association of Nitrox and Technical Divers (IANTD), Confédération Mondiale des Activités Subaquatiques (CMAS), French Federation of Speleology (FFS) diving instructor. Dive equipment Dual HammerHead rebreather of his own design. Dive record On 3 December 2011 Krzysztof Starnawski broke David Shaw's record in deep diving with a rebreather. The record-breaking dive to took place in Dahab, Egypt. See also * Deep diving * Cave diving * Technical diving Technical diving (also referred to as tec diving or tech diving) is scuba diving that exceeds the agency-specified limits of recreational diving Recreational diving or sport diving is diving for the purpose of leisure and enjoyment, usually ... References 1968 births Living people Cave diving explorers Place of birth missing (living people) Polish explorers Polish underwater divers {{Poland-bio-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Pozzo Del Merro
Pozzo del Merro is a flooded sinkhole in the countryside northeast of Rome, Italy. Situated at the bottom of an 80 m conical pit, at it is the second deepest underwater vertical cave in the world. In 2000 two ROVs were sent to explore its depths; the first, the "Mercurio (Mercury)" reached its maximum operative depth of without reaching the bottom. The second ROV, "Hyball 300", reached without touching down either. A third dive in 2002 with the more advanced "Prometeo" robot reached the bottom at , but discovered a narrow passage continuing horizontally. The sinkhole, similar to the Zacatón cenote, was formed by volcanic activity eroding the carbonate rock Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolosto .... References Sinkholes of Italy Metropolitan City of Rome Capita ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
|
Rift
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side. Where rifts remain above sea level they form a rift valley, which may be filled by water forming a rift lake. The axis of the rift area may contain volcanic rocks, and active volcanism is a part of many, but not all, active rift systems. Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates. ''Failed rifts'' are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to the poi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |