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71-499: The difference in elevation of the highest cave entrance (Arbaika) and its deepest explored point is 2,199 ± 20 metres (7,215 ± 66 ft). It became the deepest-known cave in the world in 2003 when the expedition of the Ukrainian Speleological Association reached a depth of 1,910 m (6,270 ft) which exceeded the depth of the previous deepest-known cave, Lamprechtsofen , in

142-613: A doubly plunging anticline , and may be formed from multiple deformations, or superposition of two sets of folds. It may also be related to the geometry of the underlying detachment fault and the varying amount of displacement along the surface of that detachment fault. An anticlinorium is a large anticline in which a series of minor anticlinal folds are superimposed. Examples include the Late Jurassic to Early Cretaceous Purcell Anticlinorium in British Columbia and

213-479: A high rate of compression and seismic activity due to the converging San Andreas Fault. As a result, the Ventura anticline rises at a rate of 5 mm/year with the adjacent Ventura Basin converging at a rate of about 7–10 mm/year. The anticline is composed of a series of sandstone rock beds and an impermeable rock cap under which vast reserves of oil and gas are trapped. Eight different oil bearing zones along

284-405: A large area of the eastern sector of the massif (the hypothetical "Eastern Karst Hydrological System"). It is not clear where Sarma Cave (−1,550 m) drains to, Goluboje Ozero to the southeast or Reprua to the southwest, at the shore. The results of the dye-tracing tests demonstrated that groundwater flow is not subordinate to the fold structure but is largely controlled by faults that cut across

355-531: A low overall hydraulic gradient of 0.007-0.008. Low- TDS groundwater is tapped by boreholes in the shore area at depths of 40–280, 500, 1,750, and 2,250 m below sea level, which suggests the existence of a deep flow system with vigorous flow. Submarine discharge along the Arabika coast is reported at depths up to ~400 m b.s.l. It is difficult to interpret these facts in terms of the development of karst systems controlled by contemporary sea level, or within

426-633: A primary focus for the Ukrainian efforts. This approach, followed in subsequent years by other caving clubs which joined exploration activity in different parts of Arabika, resulted in the discovery of many deep caves including five caves deeper than 1,000 m. In the Ortobalagan Valley, the Ukrainian cavers made breakthroughs in Kuybyshevskaya Cave at −160 m and pushed it to −1,110 m (−3,640 ft) by 1986 through

497-641: A role in guiding groundwater flow; the latter guide flow across the strike of major plicative dislocations, from the central sector toward the Black Sea . The cave has six entrances, in the gallery below they are arranged by altitude, highest to lowest, after the main one. All are situated above the tree line . Major on-shore karst springs with individual average discharges of 1 to 2.5 m/s (35 to 88 cu ft/s) are located at altitudes ranging from 1 m (3.3 ft) (Reprua Spring) to 540 m (1,770 ft) (Gega waterfall). Two of them are located in

568-738: A series of massive boulder chokes. They broke through an impassable squeeze at −120 m in Genrikhova Bezdna Cave and eventually connected it to Kuybyshevskaya at −956 m in 1987. The resultant system has been named the Arabikskaya System. From 1982 onwards, the Kiev cavers started systematically working in Krubera Cave, located less than 200 metres from the Kuybyshevskaya entrance, hoping to connect with

639-434: A type of anticlines that have a well-defined, but curved hinge line and are doubly plunging and thus elongate domes . Folds in which the limbs dip toward the hinge and display a more U-like shape are called synclines . They usually flank the sides of anticlines and display opposite characteristics. A syncline's oldest rock strata are in its outer limbs; the rocks become progressively younger toward its hinge. A monocline

710-455: Is a dome . Domes may be created via diapirism from underlying magmatic intrusions or upwardly mobile, mechanically ductile material such as rock salt ( salt dome ) and shale (shale diapir) that cause deformations and uplift in the surface rock. The Richat Structure of the Sahara is considered a dome that has been laid bare by erosion. An anticline which plunges at both ends is termed

781-431: Is a bend in the strata resulting in a local steepening in only one direction of dip. Monoclines have the shape of a carpet draped over a stairstep. An anticline that has been more deeply eroded in the center is called a breached or scalped anticline . Breached anticlines can become incised by stream erosion, forming an anticlinal valley. A structure that plunges in all directions to form a circular or elongate structure

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852-462: Is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the location where the curvature is greatest, and the limbs are the sides of the fold that dip away from the hinge. Anticlines can be recognized and differentiated from antiforms by a sequence of rock layers that become progressively older toward

923-401: Is cylindrical has a well-defined axial surface, whereas non-cylindrical anticlines are too complex to have a single axial plane. An overturned anticline is an asymmetrical anticline with a limb that has been tilted beyond perpendicular , so that the beds in that limb have basically flipped over and may dip in the same direction on both sides of the axial plane. If the angle between the limbs

994-547: Is large (70–120 degrees), then the fold is an "open" fold , but if the angle between the limbs is small (30 degrees or less), then the fold is a "tight" fold . If an anticline plunges (i.e., the anticline crest is inclined to the Earth's surface), it will form V s on a geologic map view that point in the direction of plunge . A plunging anticline has a hinge that is not parallel to the earth's surface. All anticlines and synclines have some degree of plunge. Periclinal folds are

1065-521: Is no mechanical contrast between layers in this type of fold. Passive-flow folds are extremely dependent on the rock composition of the stratum and can typically occur in areas with high temperatures. Anticlines, structural domes, fault zones and stratigraphic traps are very favorable locations for oil and natural gas drilling. About 80 percent of the world's petroleum has been found in anticlinal traps. The low density of petroleum causes oil to buoyantly migrate out of its source rock and upward toward

1136-591: Is one of the deepest caves in the world. Before the discovery of the Krubera Cave in Georgia , it was the deepest-known cave in the world. Lamprechtsofen is located 2 km (1.2 mi) northwest of Weißbach bei Lofer ( Salzburg ), Austria , in the Leogang Mountains . The cave has been known for centuries. In 1701 it was walled up to prevent the intrusion of treasure seekers, who were lured to

1207-428: Is one of the two known caves on Earth deeper than 2,000 metres. Georgian speleologists from "Kipiani group" who discovered the cave in the 1963 named it for Russian geographer Alexander Kruber and explored it to -57 m. In 1980's the cave was rediscovered by another group and called "Siberian cave'. And then it was rediscovered for the third time by Ukrainian speleologists in 1980s' and called "Voronya" (Crows' cave) for

1278-606: Is the El Dorado anticline in Kansas. The anticline was first tapped into for its petroleum in 1918. Soon after the site became a very prosperous area for entrepreneurs following World War I and the rapid popularization of motor vehicles . By 1995 the El Dorado oil fields had produced 300 million barrels of oil. The central Kansas uplift is an antiform composed of several small anticlines that have collectively produced more than 2.5 million barrels of oil. Another notable anticline

1349-524: Is the Peak of Speleologists (2,705 m (8,875 ft)) but the dominant summit is a typical pyramidal horn of the Arabika Mount (2,695 m (8,842 ft)). Some middle- to low-altitude ridges covered with forest lie between the central sector and the Black Sea . A plateau-like middle-altitude outlier of the massif in its south sector is Mamzdyshkha, with part of the plateau slightly emerging above

1420-548: Is the Tierra Amarilla anticline in San Ysidro, New Mexico. This is a popular hiking and biking site because of the great biodiversity, geologic beauty and paleontological resources. This plunging anticline is made up of Petrified Forest mudstones and sandstone and its caprock is made of Pleistocene and Holocene travertine. The anticline contains springs that deposit carbon dioxide travertine that help to contribute to

1491-420: Is the area on the limbs where the curvature changes direction. The axial surface is an imaginary plane connecting the hinge of each layer of rock stratum through the cross section of an anticline. If the axial surface is vertical and the angles on each side of the fold are equivalent, then the anticline is symmetrical. If the axial plane is tilted or offset, then the anticline is asymmetrical. An anticline that

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1562-443: Is the relative ages of the rock strata that distinguish anticlines from antiforms. The hinge of an anticline refers to the location where the curvature is greatest, also called the crest . The hinge is also the highest point on a stratum along the top of the fold. The culmination also refers to the highest point along any geologic structure. The limbs are the sides of the fold that display less curvature. The inflection point

1633-424: Is to bend a deck of cards and to imagine each card as a layer of rock stratum. The amount of slip on each side of the anticline increases from the hinge to the inflection point. Passive-flow folds form when the rock is so soft that it behaves like weak plastic and slowly flows. In this process different parts of the rock body move at different rates causing shear stress to gradually shift from layer to layer. There

1704-564: The Arabika Massif began in 1980 when the Kiev Speleological Club, led by Alexander Klimchouk, started exploring caves there. They adopted an approach to cave search and exploration which included thorough investigations in a defined area and systematic testing of cave limits, through digging in boulder chokes and enlarging squeezes which had previously obstructed exploration. The Ortobalagan Valley had been selected as

1775-572: The Austrian Alps , by 80 metres (260 ft). In 2006, for the first time in the history of speleology , the Ukrainian Speleological Association expedition reached a depth greater than 2,000 metres (6,600 ft), and explored the cave to −2,080 m (−6,824 ft). Ukrainian diver Gennadiy Samokhin extended the cave by diving in the terminal sump to 46 metres' depth in 2007 and then to 52 m in 2012, setting successive world records of 2,191 m and 2,197 m, respectively. Krubera

1846-554: The Black Sea and plunge below the modern sea level. To the northwest, north, northeast, and east, Arabika is bordered by the deeply incised canyons of Sandripsh, Kutushara, Gega and Bzyb rivers. The Bzyb River separates Arabika from the adjacent Bzybsky Massif, another outstanding karst area with many deep caves, including the Snezhnaja-Mezhonogo-Iljuzia System (−1,753 m or −5,751 ft) and Pantjukhina Cave (−1,508 m or −4,948 ft). To

1917-653: The Blue Ridge anticlinorium of northern Virginia and Maryland in the Appalachians, or the Nittany Valley in central Pennsylvania. Anticlines are usually developed above thrust faults, so any small compression and motion within the inner crust can have large effects on the upper rock stratum. Stresses developed during mountain building or during other tectonic processes can similarly warp or bend bedding and foliation (or other planar features). The more

1988-463: The structural trap for the largest conventional oil field in the world. The Weald–Artois Anticline is a major anticline which outcrops in southeast England and northern France. It was formed from the late Oligocene to middle Miocene , during the Alpine orogeny . Anticlines can have a major effect on the local geomorphology and economy of the regions in which they occur. One example of this

2059-403: The Arabikskaya System and increase its total depth by 60 m. Exploration progressed slowly because critically tight meanders between the pits required enormous amounts of work to widen them to a passable size. The cave was pushed to −340 m during 1982–1987. Two "windows" in a vertical shaft at depths of 220–250 m were documented on the cave map but remained unexplored. During this time

2130-629: The Gega canyon (1 m/s or 35 cu ft/s; 540 m or 1,770 ft a.s.l.). There are also several smaller springs in the Gagra town. The Reprua River , one of the shortest rivers in the world, about 60 feet (18 m) long, starts in the cave and flows toward the Black Sea . Some boreholes located along the shore of the Black Sea yield karstic groundwater from depths of 40–280 m below sea level. Other much deeper boreholes tapped low-salinity karstic waters at depths of 500 and 1,750 m in

2201-493: The Khashupse Valley near Gantiadi and 2,250 m near Gagra. This suggests the existence of a deep karst system and vigorous karst groundwater circulation at depth. Submarine springs are known in the Arabika area, emerging from the floor of the Black Sea in front of the massif. Shallow springs at depths of 5–7 m can be reached by free dive near Gantiadi. Tamaz Kiknadze (1979) reported submarine springs near

Krubera Cave - Misplaced Pages Continue

2272-592: The Krubera explorations by the Ukr.S.A. have been undertaken within the frame of the multi-year project named "The Call of the Abyss", coordinated by A. Klimchouk, Y. Kasyan, G. Samokhin and K. Markovskoy. Besides the Ukrainian speleologists, cavers from many countries such as France, Spain, Russia, Moldova , Bulgaria , United Kingdom, Ireland, Israel and Lithuania have taken part in different expeditions of

2343-694: The Kujbyshevskaja Cave and the Iljukhina System were detected in the Kholodnaja Rechka and Reprua springs, proving groundwater flow to the south-southwest across major tectonic structures over a distance of 13–16 km as the crow flies (Figure 1). The tracer from Kujbyshevskaja Cave was also detected in a borehole located between these two springs, which yields groundwater from a depth of 200 m (660 ft) below sea level. This has been interpreted as an indication of

2414-588: The Main Branch was quickly pushed by the multi-stage expedition of the Ukr. S.A. in August to −1,200 m and in September to −1,410 m. In January 2001, the Ukr.S.A. expedition explored the cave to −1,710 m (−5,610 ft) making it the deepest cave in the world. For the first time in the history of speleology, the deepest cave in the world had been established outside of western Europe. Since 2001,

2485-460: The Ortobalagan Valley and named it after Alexander Kruber . The first explorers were stopped by impassable squeezes at −95 m in a meandering passage which led off from the foot of the entrance shaft. The cave remained largely neglected over the next 20 years, although occasionally visited by cavers from various caving clubs. Before 1980 there were no caves deeper than 310 m (1,020 ft) known in Arabika. The new era in cave explorations in

2556-511: The Ortobalagan Valley likely belong to a single hydrological system, connected to large submarine springs at the Black Sea shore. The Ortobalagan Valley extends along the crest of the Berchil'sky anticline , which gently plunges northwest. The cave entrances are aligned along the anticlinal crest (Figure 2) but the caves are controlled by longitudinal, transverse, and oblique fractures and faults and exhibit complex winding patterns in

2627-462: The Ukr.S.A. The major events in the exploration of Krubera Cave in subsequent years were as follows (see Figure 4 for spot locations): Lamprechtsofen Lamprechtsofen (also called Lamprechtshöhle , Lamprechtsofenhöhle or, together with a connected cave, Lamprechtsofen-Vogelschacht ) is a limestone karst river cave in Austria . With a depth of 1,735 m (5,692 ft), it

2698-630: The Upper Jurassic succession resting on the Bajocian Porphyritic Series, which includes sandstones , clays and conglomerates at the top, and tuff , tuffaceous sandstones , conglomerates and breccia , porphyry and lava . The Porphyritic series forms the non-karstic basement of Arabika, which is exposed only on the northern and eastern outskirts, locally in the bottoms of the Kutushara and Gega River valleys. In

2769-493: The Zhovekvara River mouth, which has dimensions of about 5 x 9 km and a maximum depth of about 380 m (1,250 ft). The Arabika Submarine Depression is a closed feature with internal vertical relief of about 120 m (390 ft) (measured from its lowest rim) separated from the abyssal slope by the bar at a depth of about 260 m (850 ft). It has steep northern and northeastern slopes (on

2840-476: The anticline roughly coincides with the ridge bordering the Gelgeluk Valley to the north. Located on the southwestern flank of the major anticline is another large one (Berchil'sky), in which the crest is breached by the Ortobalagan Valley. There are several smaller sub-parallel anticlines and synclines farther southwest, between the Berchil' Ridge and the coast. The plicative dislocation structure of

2911-490: The cave by legends of wealth hidden by a knight named Lamprecht after the Crusades . In 1905, several human skeletons were found in the cave, probably the remains of treasure hunters. At the same time, a 600-metre (2,000 ft) portion of the cave was opened to the public as a show cave . The exploration of Lamprechtsofen has been primarily conducted from the bottom (from the resurgence of its cave river ), rather than

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2982-502: The cave received its second, alternative name Voronja (Crows') Cave, owing to the number of crows nesting in the entrance shaft. The political and ethnic conflict in Abkhazia during 1992–94 resulted in instability and border problems which continued over subsequent years. This suspended speleological explorations in Arabika. Some stabilization of the situation in 1998 has since enabled a renewal of exploration effort to take place in

3053-418: The cavity to reach the depth of 1735 m. Today, about 700 m (2,300 ft) are open to visitors, a portion of the cave that covers a 70-metre (230 ft) altitude difference. Because of the cave's river, it is subject to flooding from heavy rain and melting snow. As such, visitors and explorers have been occasionally trapped in the cave. Anticline In structural geology , an anticline

3124-429: The center of the fold. Therefore, if age relationships between various rock strata are unknown, the term antiform should be used. The progressing age of the rock strata towards the core and uplifted center, are the trademark indications for evidence of anticlines on a geologic map . These formations occur because anticlinal ridges typically develop above thrust faults during crustal deformations. The uplifted core of

3195-686: The central part of Arabika the Cretaceous cover ( Valanginian and Hauterivian limestones, marls and sandstones) is retained only in a few ridges and peaks, but it lies intact through the low-altitude ridges to the south-west of the central part. There the Cretaceous succession includes Barremian and Aptian – Cenomanian limestones and marly limestones with abundant concretions of black chert . The Upper Jurassic succession begins with thin-bedded Kimmeridgian – Oxfordian cherty limestones, marls, sandstones and clays , which are identified in

3266-423: The connection of the cave with the submarine discharge. The large "Central Karst Hydrologic System", which encompasses most of the southeastern flank of the Arabika anticline, had been identified in this way. The system became the deepest in the world with its overall vertical range of about 2,500 m (8,200 ft) (measuring to the borehole water-bearing horizon) or even 2,700 m (8,900 ft) (measuring to

3337-472: The crows nesting in the entrance pit. Only later exchange of information between the caving clubs allowed them to discover they explored same cave. The Arabika Massif , the home of Krubera (Voronya) Cave, is one of the largest high-mountain limestone karst massifs in the Western Caucasus. It is composed of Lower Cretaceous and Upper Jurassic limestones that dip continuously southwest to

3408-506: The deepest part of the Krubera Cave (at the depth of −2,175 metres). At the beginning of the 20th century, Arabika was visited by French speleologist Édouard-Alfred Martel , who published several works about the massif. In 1909–10 Russian karst scientist Alexander Kruber, a founder of the study in Russia, performed some field studies in Arabika. He published his observations in a series of Arabika-specific papers and several monographs . During

3479-623: The deepest reported submarine discharge points). Another tracer was injected in the Moskovskaja Cave (−970 m) and detected at the Gegsky Vodopad spring, indicating the presence of a karst hydrologic system comprising the northeastern flank of the Arabika anticline (the "Northern System"). No connections have been revealed with yet another major spring, Goluboje Ozero in the Bzyb River canyon, although it apparently drains

3550-604: The dramatic sea level drop of ~1,500 m is well established. The biocenosis of Krubera-Voronja is composed of more than 12 species of arthropods of several groups, such as pseudoscorpions , spiders , opiliones , crustaceans , springtails , beetles and dipterans . Krubera-Voronja cave is inhabited by endemic species, including four springtails discovered during the CAVEX Team expedition of 2010: Anurida stereoodorata , Deuteraphorura kruberaensis , Schaefferia profundissima , and Plutomurus ortobalaganensis ;

3621-410: The eastern part of Gagra at depth of 25–30 m and Buachidze and Meliva (1967) revealed submarine discharge at depths up to −400 m by hydrochemical profiling. Recently an outstanding feature of the sea floor topography near Arabika has been revealed from a digital bathymetric map that combines depth soundings and high-resolution marine gravity data. This is a huge submarine depression in front of

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3692-399: The fold causes compression of strata that preferentially erodes to a deeper stratigraphic level relative to the topographically lower flanks. Motion along the fault including both shortening and extension of tectonic plates, usually also deforms strata near the fault. This can result in an asymmetrical or overturned fold. An antiform can be used to describe any fold that is convex up. It

3763-475: The last of these is the deepest terrestrial animal ever found on Earth , living 1,980 metres (6,500 ft) below the cave entrance. The beetle Catops cavicis inhabits Krubera-Voronja cave and also several caves around the Ortobalagan Valley . The subterranean amphipod crustacean Kruberia abchasica caught by Gennady Samokhin in August 2013, during dives in the siphon 'Dva Kapitana', dwells at

3834-533: The lower part of Krubera Cave. Above lies the thick Tithonian succession of thick-bedded limestones with marly and sandy varieties. Sandy limestones are particularly abundant through the upper 1,000 m sections of deep caves of the Ortobalagan Valley. The tectonic structure of Arabika is dominated by the axis of the large sub-Caucasian anticline (oriented NW–SE), with the gently dipping southwestern mega-flank, complicated by several low-order folds, and steeply dipping northeastern flank (Figure 3). The axis of

3905-497: The massif is severely complicated by faults, with the fault-block structure strongly controlling both cave development and groundwater flow. Major faults of the sub-Caucasian orientation delineate several large elongated blocks that experienced uplift with different rates during Pliocene and Pleistocene . This had a pronounced effect on the development of deep groundwater circulation and of Krubera Cave in particular. Both longitudinal and transverse faults and related fracture zones play

3976-470: The non-Kujbyshevskaja branch of Krubera Cave, etc.). The deep parts of Krubera display a more pervasive conduit pattern with a mixture of phreatic morphology, characteristic of the zone of high-gradient floods, which can be up to 400 m above the low-flow water table, and vadose downcutting elements that are observed even below the water table. The core part of the Arabika Massif is composed of

4047-492: The plan view, remaining largely within and near the anticlinal crest zone. The caves are predominantly combinations of vadose shafts and steep meandering passages, although in places they cut apparently old fossil passages at different levels (e.g., at −2,100–2,040 m (−6,890–6,690 ft) in Kujbyshevskaja and Krubera caves, −1,200–1,240 m (−3,940–4,070 ft) and −980–1,150 m (−3,220–3,770 ft) in

4118-547: The range of its Pleistocene fluctuations (up to −150 m). In combination with the existence of the Arabika Submarine Depression, all these facts point to the possibility that karst systems in Arabika could have originated in response to the Messinian salinity crisis (5.96–5.33 Ma) when the Black Sea (Eastern Paratethys ) could have almost dried up, as did the adjacent Mediterranean , where

4189-583: The region. In 1999, the expedition of the Ukrainian Speleological Associations (Ukr. S.A.) led by Jurij Kasjan (also spelled Yuriy Kasyan) made a major breakthrough in Krubera Cave by discovering and exploring two branches behind the windows at a depth of 220–250 m. These branches stretched in two different directions. The "Main Branch" was explored to −740 m and the "Nekuybyshevskaya Branch" to −500 m. In 2000,

4260-628: The rich diversity of microorganisms. This area also contains remains of fossils and ancient plants from the Jurassic period that are sometimes exposed through geological erosion. The Ventura Anticline is a geologic structure that is part of the Ventura oil fields , the seventh largest oil field in California that was discovered in the 1860s. The anticline runs east to west for 16 miles, dipping steeply 30–60 degrees at both ends. Ventura County has

4331-445: The seashore. Since 1980, Ukrainian cavers have been undertaking systematic efforts in exploring deep caves in the Ortobalagan Valley, resulting in exploration of the Krubera Cave to its current depth and of the surrounding caves, now mostly connected to it. Another deep cave in the valley, located in its very upper part and explored by Moldavian and Ukrainian cavers is Berchilskaya Cave, 770 m (2,530 ft) deep. All large caves of

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4402-507: The shore area; these are Reprua (average discharge 2.5 m/s or 88 cu ft/s; altitude 1 m or 3 ft 3 in above sea level) and Kholodnaja Rechka (1.2 m/s or 42 cu ft/s; 50 m or 160 ft a.s.l.). Two more major springs are located in the river canyons bordering Arabika to the east: Goluboe Ozero in the Bzyb canyon (2.5 m/s or 88 cu ft/s; 90 m or 300 ft a.s.l.) and Gega waterfall in

4473-567: The side of the massif) and gentle south and southwestern slopes. Its formation is apparently karstic. Presently this depression seems to be a focus of submarine discharge of the karst systems of Arabika. The speleological explorations and a series of dye tracing experiments conducted during the 1980s under the coordination of Alexander Klimchouk have radically changed previous notions of the hydrogeology of Arabika, revealed its outstanding speleological perspectives and strongly stimulated further efforts for exploration of deep caves. Tracers injected in

4544-526: The southwest, Arabika borders the Black Sea . The Arabika Massif has a prominent high central sector with elevations above the tree line at ~1,800–1,900 m (5,900–6,200 ft). This is an area of classical glaciokarstic landscape, with numerous glacial trough valleys and cirques, with ridges and peaks between them. The bottoms of trough valleys and karst fields lie at elevations of 2,000–2,350 m (6,560–7,710 ft), and ridges and peaks rise to 2,500–2,700 m (8,200–8,900 ft). The highest peak

4615-426: The strike of major folds, and that the large part of the central sector of Arabika is hydraulically connected to the springs along the seashore and with submarine discharge points. Krubera Cave has an extremely steep profile and reveals a huge thickness of the vadose zone. The lower boundary of the vadose zone (the top of the phreatic zone) is at an elevation of about 110 m (360 ft) at low flow, which suggests

4686-427: The subsequent 50 years no special studies were undertaken of the karst and caves in the region, although the karst of Arabika was referred to in many works dealing with regional geology and hydrogeology. In the early 1960s, Georgian geographers led by Levan Maruashvili began exploring caves in the high sector of the massif. Among several other caves, they made the first exploration of an open-mouthed 60 m shaft in

4757-786: The surface until it is trapped and stored in reservoir rock such as sandstone or porous limestone. The oil becomes trapped along with water and natural gas by a caprock that is made up of impermeable barrier such as an impermeable stratum or fault zone. Examples of low-permeability seals that contain the hydrocarbons, oil and gas, in the ground include shale , limestone , sandstone , and rock salt. The actual type of stratum does not matter as long as it has low permeability. Water, minerals and specific rock strata such as limestone found inside anticlines are also extracted and commercialized. Lastly, ancient fossils are often found in anticlines and are used for paleontological research or harvested into products to be sold. Ghawar Anticline, Saudi Arabia,

4828-461: The top-down exploration typical for vertical caves. On August 19, 1998, a team led by Polish caver Andrzej Ciszewski discovered a connection between Lamprechtsofen and the PL-2 cave system, which established the height difference of the united cave system as 1,632 m (5,354 ft). This new discovery made Lamprechtsofen the deepest-known cave in the world for less than three years, as Krubera

4899-408: The tree line. Among several hundred caves known in the Arabika Massif, fifteen have been explored deeper than 400 m and five deeper than 1,000 m. Krubera Cave is located at 2,256 m above sea level in the Ortobalagan Valley, a perfectly shaped, relatively shallow, glacial trough of the sub- Caucasian stretch, which holds the advanced position in the Arabika's central sector relative to

4970-435: The underlying fault is tectonically uplifted, the more the strata will be deformed and must adapt to new shapes. The shape formed will also be very dependent on the properties and cohesion of the different types of rock within each layer. During the formation of flexural-slip folds, the different rock layers form parallel-slip folds to accommodate for buckling . A good way to visualize how the multiple layers are manipulated,

5041-586: Was discovered in June 2001 to be 2,197 metres (7,208 ft) deep. As of 2014, Lamprechtsofen is the fourth-deepest cave in the world, as two more Georgian caves have since been discovered to be deeper. Sarma Cave is 1,830 m (6,000 ft) and Illyuzia-Mezhonnogo-Snezhnaya Cave is 1,753 m (5,751 ft). On August 14, 2018 a Polish expedition connects the CL3 chasm to the Lamprechtsofen allowing

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