Voska luknja

Voska luknja
LocationOčura
Coordinates46°11′03″N 15°53′36″E / 46.184293°N 15.893218°E / 46.184293; 15.893218[1][2]
Depth22 metres (72 ft)[3]
Length40.7 metres (134 ft)[4][5][3]
Elevation509 metres (1,670 ft)[6]
DiscoveryAugust 2009[7]
GeologyKarst cave
Entrances2
Cadastral codeHR00273[3]

Voska luknja is a cave on the north slope of the Ivanščica massif. It is a diagonal cave, so its horizontal length of 25 metres (82 ft) is much smaller than its total passage length of 40.7 metres (134 ft). As mapped, it is the second deepest cave on Ivanščica behind Hanžekova jama at 22 metres (72 ft),[3] but its total vertical difference is the largest in Zagorje, with potential for further expansion It is difficult to explore because of its narrowness and the entrance is difficult to access, but a tourist path has been planned.

Name

The name Voska luknja is Kajkavian for "Narrow Hole" (Croatian: Uska rupa).[8]

Description

The cave is located on the slopes of the Dubrava peak. It is an exceptionally narrow cave, partly tectonic in origin,[8][9] whose widest section is only 70 centimetres (2.3 ft) wide.[10] It is a cascading cave entered from the side with continuations both at the top and at the bottom for a total known vertical difference so far of 38.2 metres (125 ft),[5] but these narrows are impassible without modification. The main chamber leads upwards and goes by the name Veliki kanal. The chamber leading downwards has been nicknamed Banana, ending on a ledge with a narrow continuation. At the far end of the floor of the Veliki kanal there is a narrow downward continuation nicknamed Cerviks, and at the roof there are as many as 4 possible continuations, all very narrow.[4]

Speleothems include stalactites, stalagmites, and coralloids, but flowstone dominates, including Cave curtains. A cluster of calcite crystals was found contrasting with brown hematite coloration at a depth of 25 metres (82 ft) below the entrance.[7]

A map of the cave was drawn in September 2009 by Tomica Matišić.[4][10]

History

Cavers from the newly founded[11] HSS section Kraševski Zviri discovered both the lower and the upper entrance in August 2009,[7] exploring much of the lower entrance that year.[12] Exploration resumed in June 2010, adding another 10 metres (33 ft) downward. It was during this exploration that Voska špilja was discovered not far above it.[9] Its regionally unusual depth (initially 30 metres (98 ft)),[7] proximity to Voska špilja and the potential for a connection to result in a cave with a cumulative depth of around 50 metres (160 ft), unusual for the region, made it an attractive target for exploration and garnered significant media attention,[13] and before the discovery of Gliboka jama was sometimes regarded as the deepest cave in Zagorje.[14][15] In July 2011, the widening of the upper passage with a rock chisel increased its explored length by 8 metres (26 ft), with ultimate the aim of connecting it to Voska špilja. Fox bones hinted at a buried intermediary entrance, but they were still far away from Voska špilja.[8][9]

Paleontology

A Cervus elaphus antler was discovered in one of the meanders, possibly brought there during a flooding episode, along with Vulpes vulpes bones in a blind passage of the upper section near a buried upper entrance.[16]

Climate

The air temperature of the cave is 10.7 °C (51.3 °F), and its soil temperature 10.2 °C (50.4 °F). Its relative humidity is 98%.[9] Its radon concentration was measured in 2012–2013.[17][18]

The cave is not hydrologically active. Seepage dominates in the lower levels.[7]

Biology

Species found in the cave include members of the Araneae, Coleoptera, Gastropoda, and Lepidoptera. A Rhinolophus species was identified.[9]

Tourism

A tourist path has been planned from Šumec to Bračkova jama and Bračkova špilja, and from there to Voska luknja and Voska špilja, then to Šumec and Karlova špilja, then to Generalka and Polušpilja Generalski Stol.[12][19]

See also

References

  1. ^ Matišić 2012, p. 24,43.
  2. ^ Kraš 2017, p. 36.
  3. ^ a b c d Speleološka udruga "Kraševski zviri" 2015.
  4. ^ a b c Matišić 2012, p. 24.
  5. ^ a b Matišić 2014, p. 15.
  6. ^ Matešić 2012, p. 24.
  7. ^ a b c d e Matišić 2012, p. 21.
  8. ^ a b c Risek 2011.
  9. ^ a b c d e Matišić 2012, p. 22.
  10. ^ a b Kraš 2017, p. 34.
  11. ^ Matišić 2014.
  12. ^ a b Risek 2010.
  13. ^ eVaraždin 2018.
  14. ^ prigorski.hr 2023.
  15. ^ Blotnej 2023.
  16. ^ Matišić 2012, p. 21,22.
  17. ^ Matišić 2012, p. 40.
  18. ^ Regionalni Tjednik 2013.
  19. ^ Matišić 2012, p. 43.

Bibliography

This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.