Krubera Cave - Georgia (Deepest Cave)

The Krubera Cave (or the Voronya Cave sometimes spelled Voronja Cave) is the deepest known cave on Earth. It is located in the Arabika Massif of the Gagrinsky Range of the Western Caucasus, in the Gagra district of Abkhazia, Georgia’s breakaway republic.

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The difference in the altitude of the cave's entrance and its deepest explored point is 2,191 ± 20 metres (7,188 ± 66 ft). It became the deepest-known cave in the world in 2001 when the expedition of the Ukrainian Speleological Association reached a depth of 1,710 m (5,610 ft) which exceeded the depth of the previously deepest cave, Lamprechtsofen, in the Austrian Alps, by 80 m. In 2004, for the first time in the history of speleology, the Ukrainian Speleological Association expedition reached a depth greater than 2,000 m, and explored the cave to −2,080 m (−6,824 ft). The current maximum depth of 2,191 m was reached during a 46 m dive by Gennadiiy Samokhin into the terminal sump during the expedition of the Ukrainian Speleological Association in August–September 2007. The cave remains the only known cave on Earth deeper than 2,000 metres.

Location And Background

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 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 −5,751.3 ft) and Pantjukhina Cave (−1,508 m or −4,947.5 ft). To 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 (6,600–7,710 ft), and ridges and peaks rise to 2,500–2,700 m (8,200–8,900 ft). The highest peak 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 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 (shown in Figure 1).

Krubera Cave is located at 2,256 m asl 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 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 Arabikskaja System to depth of −1,110 m (−3,641.7 ft). The latter consists of Kuybushevskaya Cave (also spelled as Kujbyshevskaja; −1,110 m) and Genrikhova Bezdna Cave (−965 m to the junction with Kujbyshevskaja). Another deep cave in the valley, located in its very upper part and explored by Moldavian and Ukrainian cavers is Berchilskaya Cave, 500 m (1,600 ft) deep. All large caves of the Ortobalagan Valley likely belong to a single hydrological system, connected to large springs at the Black Sea shore. The direct physical connection of Krubera Cave with the Arabikaskaja System is a sound possibility, although not yet physically realized.

http://en.wikipedia.org/wiki/Krubera_Cave