Ledena pecina/Ice cave, Durmitor
Ledena pecina is an ice cave in the massif of Obla glava (2303 meters above sea).
Obla Glava (2303 m) peak is placed in the heart of highest mountains of Durmitor massif. It's beautiful summit is surrounded by impressive and elegant forms of many peaks like Bobotov Kuk (2523 m), Bezimeni Vrh (2487 m), Rbatina (2401 m) and Minin Bogaz (2387 m).
The cave itself is 40m long and 20m wide. Even in hot summer it keeps the ice-tongue in the entry. Stalagmites and stalactites in the bottom reach height of adult person and create impressive view for visitors. Despite low temperature is the cave inhabited by endemite organisms. In the cave vicinity, as well as in the whole Durmitor, we can find variety of flowers including endemites.
Durmitor National Parkcomprises Mount Durmitor plateau and the valley formed by the canyon of the River Tara, incorporating three major geomorphologic features: canyons, mountains and plateaux. Because of its geographical location and range in altitude, the park is under the influence of both Mediterranean and alpine microclimates, which has resulted in an exceptional range of species.
Geologically, Durmitor and Tara canyons are made up of rocky massifs of the Mesozoic era (from the Lower Triassic to the Upper Cretaceous), Tertiary and Quaternary periods. The dominant features are the limestone formations of the Middle and Upper Triassic, the Upper Jurassic and the Upper Cretaceous, especially the so-called Durmitorean flysch. The River Tara, one of the last wild rivers in Europe, has pure, clear waters, a gorge 1,300 m deep and notable floristic and faunistic diversity. The 16 glacial lakes of the Durmitor and the canyons of the Tara, Susica and Draga rivers were formed during the Quaternary period, following the sudden thaw of the snow and the formation of glaciers on the Durmitor and neighbouring mountains. The waters of the largest lake, Black Lake, feed two separate river basins: the River Tara, and underground through the Durmitor Massif, the River Komarnica or Piva. There are numerous examples of weathering processes, rock shapes and land features characteristic of karstic erosion, fluvial erosion and glacial erosion.
Ice caves
The term ice cave refers to any type of natural cave (most commonly lava tubes or limestone caves) that contains significant amounts of perennial (year-round) ice. At least a portion of the cave must have a temperature below 0 °C (32 °F) all year round, and water must have traveled into the cave’s cold zone.
Temperature mechanisms
Bedrock caves are thermally insulated from the surface, so commonly assume a near-constant temperature approximating the annual average temperature at the surface. In some cold environments, average surface (and thus cave) temperatures are below freezing, and with surface water available in summer, ice caves are possible. However, many ice caves exist in temperate climates, due to mechanisms that result in cave temperatures being colder than average surface temperatures where they formed.
Cold traps - Certain cave configurations allow seasonal convection to import cold air from the surface in winter, but not warm air in summer. A typical example is an underground chamber located below a single entrance. In winter, cold dense air settles into the cave, displacing any warmer air which rises and exits the cave. In summer, the cold cave air remains in place as the relatively warm surface air is lighter and cannot enter. The cave will only exchange air when the surface air is cooler than the cave air. Some cold traps may ensnare surface snow and shade it from the summer sun’s rays, which may further contribute to the colder cave temperature.
Permafrost- Even temperate environments can include pockets of bedrock that are below freezing year round, a condition called permafrost. For example, winter wind and an absence of snow cover may allow freezing deep enough to be protected from summer thaw, particularly in light-colored rock that does not readily absorb heat. Although the portion of a cave within this permafrost zone will be below freezing, permafrost generally does not allow water percolation, so ice formations are often limited to crystals from vapor, and deeper cave passages may be arid and completely ice-free. Ice caves in permafrost need not be cold-traps (although some are), provided they do not draught significantly in summer.
Evaporative cooling - In winter, dry surface air entering a moisture-saturated cave may have an additional cooling effect due to the latent heat of evaporation. This may create a zone within the cave that is cooler than the rest of the cave. Because many caves have seasonally-reversing draughts, the corresponding warming of the cave through condensation in summer may occur at a different location within the cave, but in any event a moisture-saturated cave environment is likely to experience much more evaporative cooling than condensative warming.
Types of ice in ice caves
Different freezing mechanisms result in visually and structurally distinct types of perennial cave ice.
Ponded water - Surface water that collects and ponds in a cave before freezing will form a clear ice mass, and can be tens of metres thick and of great age. Large ice masses are plastic and can slowly flow in response to gravity or pressure from further accumulations. Sculpting from air flow and sublimation may reveal ancient accumulation bands within the ice.
Accumulated snow - Compressed under the weight of ongoing accumulations, snow sliding or falling into a cave entrance may eventually form ice that is coarsely crystalline, akin to glacier ice. True underground glaciers are rare.
Ice formations - Water that freezes before ponding may form icicles, ice-stalagmites, ice columns or frozen waterfalls.
Airborne moisture (water vapor) – Freezing vapor can form frost crystals, frost feathers and two-dimensional ice plates on the cave walls and ceiling.
Needle ice- Infiltrating water that freezes within the bedrock can sometimes be forced into the cave passage.
Intrusions- The weight of a surface glacier perched atop a cave entrance can force glacial ice a short distance into the cave. The only known examples of this phenomenon are the several 'ice plugs' at the back of Castleguard Cave in Alberta.
How to log the cache?
For acceptance of your log send the following answers through our profile prior to logging the cache:
1) Which ice formations you could observe in the cave?
2) What type of temperature mechanism was this cave created by?
As option, please add a photo of yourself with your GPS OUTSIDE the cave to the log.(Photo is not a condition for log approval.)
You can log your visit before getting confirmation of your correct answers, we will inform you in case of incorrect ones.
Please take your trash back down from Ledena Pecina and help to keep it clean.
Montenegrin version:
Ledena pecina je ledena pecina na masivu Oble Glave. (2303 metara iznad mora).
Vrh Oble Glave (2303 m) se nalazi u srcu najvecih planina masiva Durmitor. Njegov prelepi vrh je okružen impresivnim i elegantnim oblicima mnogih drugih vrhova, kao što su Bobotov Kuk (2523 m), Bezimeni Vrh (2487 m), Rbatina (2401 m) i Minin Bogaz (2387 m).
Pecina je 40m dugacka i 20m široka. Cak i tokom vrelih leta zadržava svoj ledeni jezik na samom ulazu. Stalagmiti i Stalaktiti na dnu dostižu visinu odrasle osobe i stvaraju impresivan pogled za posetioce. Uprkos niskim temperaturama u pecini, ona je naseljena endemitima. U blizini pecine, kao i na celom Durmitoru, može se naci velika raznovrsnost cveca, ukljucujuci endemite.
Durmitorski Nacionalni Park cini plato planine Durmitor, kao i dolina formirana kanjonom reke Tara, zajedno cineci tri znacajne geomorfološke lokacije: kanjone, planine i plato. Zbog svog geografskog položaja i varijacije u nadmorskoj visini, park je pod uticajem Mediteranske i Alpske mikroklime, što je rezultiralo širokim spektrom vrsti koje ovde opstaju.
Geološki, Kanjone Durmitora i Tare cine kamenjarski masivi iz ere Mezozika (od mladje Triasik ere do kasnije doba krede), Torcijarnom i Kvartaratnom periodu. Dominantne osobine su krecnjacke formacije srednjeg i kasnije Triasik ere, kasnije jurasik kao i Kricansko doba, narocito takozvani Durmitorski flajk. Reka Tara, jedna od poslednjih divljih reka Evrope, poseduje ciste, prozirne vode, 1,300 m duboku klisuru i primetno raznoliku floru i faunu. 16 ledenih jezera Durmitor planine i kanjoni Tare, Susice and Draga reke su formirane tokom kvartarnog perioda, pracene naglim topljenjem snega i formacija glecera sa Durmitora i okolnih planina. U vode najveceg jezera, Crnog jezera, se ulivaju dva zasebna sliva: reka Tara, i podzemna kroz Durmitorski masiv, Reka Komarnica ili Piva. Postoji više primera procesa vremena, kamenitih formacija i zemlje karakteristicne za karstnu, fluvijalnu i glecarsku eroziju.
Ledene Pecine
Pojam Ledene pecine se odnosi na tip prirodnih pecina (najcešce cevi lave ili krecnjacke pecine) koje sadrže veliki broj perinarijalnog (celogodisnjeg) leda. Barem deo pecine mora imati temperaturu ispod 0 °C (32 °F) cele godine.
Temperaturni mehanizmi
Temelji pecina su toplotno izolovani od površine, tako da se obicno predpostavlja skoro konstantna temperatura koja je približna prosjecnoj godišnjoj temperaturi na površini. U nekim hladnim sredinama (a time i u pecinama) prosjecna temperatura je ispod nule, a sa površinskim vodama koje se pojavljuju ljeti, moguce je stvaranje ledenih pecina. Medutim, mnoge ledene pecine opstaju u umjerenim klimatskim uslovima i to zahvaljujuci mehanizmima, koji u pecinu dovode temperaturu koja je hladnija od prosjecne temperature zemljine površine gde su se formirale.
Hladne klopke – Odredene konfiguracije pecine omogucavaju sezonsko strujanje hladnog vazduha sa površine tokom zime, ali ne i toplog vazduha tokom ljeta. Tipican primer je podzemna komora koja se nalazi ispod samog ulaza. Tokom zime, hladan gusti vazduh se ustaljuje u pecini, potiskujuci bilo kakav topliji vazduh koji raste i napušta pecinu. Ljeti, hladan pecinski vazduh ostaje na svom mjestu jer je relativno topli vazduh zemljine površine lakši i ne može da ude. Pecina razmjenjuje vazduh samo onda kada je površinski vazduh hladniji od pecinskog. Neke hladne klopke mogu uhvatiti u zamku površinski snijeg i tako praviti zaštitu od suncevih zraka, što može dodatno da doprinese održavanju hladnije pecinske temperature.
Permafrost – Cak i umjerenim sredinama mogu da postoje zemljišni temelji koji su ispod nule tokom cijele godine i takvo stanje se naziva permafrost (vjeciti led). Na primer, zimski vjetar i odsustvo sniježnog pokrivaca omogucavaju dovoljno duboko zamrzavanje da budu zašticene od topljenja tokom ljeta, posebno u stenama svetlije boje koje teško apsorbuju toplotu. Iako ce dio pecine u okviru zone vecitog leda biti ispod tacke smrzavanja t.j. nule, permafrost generalno ne dozvoljava filtriranje vode, tako da su ledene formacije cesto ogranicene kristalima od pare, a dublji pecinski dijelovi mogu biti suvi i u potpunosti bez leda. Uz pretpostavku da su promaje tokom ljeta beznacajne ledene pecine u permafrostu ne moraju da budu hladne klopke (mada neke to i jesu).
Rashladivanje putem isparavanja – Tokom zime, suv površinski vazduh ulazi u vlagom natopljenu pecinu i zbog latentne toplote isparavanja to može imati dodatni efekat hladenja Ovo može u pecini formirati oblast koja je hladnija od ostatka pecine. Pošto mnoge pecine imaju senzonski preusmjerene promaje, odgovarajuce zagrevanje pecine putem kondenzacije tokom ljeta može prouzrokovati pojavljivanje na drugim mjestima unutar pecine. U svakom slucaju, vlagom natopljena okolina pecine ce najvjerovatnije prouzrokovati rashladivanje putem isparavanja nego zagrijevanje putem kondenzacije.
Vrste leda u ledenim pecinama
Razliciti mehanizmi zamrzavanja dovode do razlicitih vrsti vecitih ledenih pecina, kako strukturno tako i na vizuelan nacin.
Sakupljena voda t.j. bare – površinske vode koje se skupljaju i prave bare u pecinama ce prije zamrzavanja formirati jasnu masu leda koja može biti debela nekoliko desetina metara i može biti velike starosti. Velike ledene mase su plasticne i mogu plutati u zavisnosti od gravitacije ili pritiska od daljeg gomilanja. Tesanje t.j. formiranje iz protoka vazduha i sublimacije mogu otkriti drevno nagomilavanje trakastih oblika u ledu.
Nagomilani snijeg – Zbijen pod teretom u toku akumulacija t.j. nagomilavanja, snijeg klizi ili pada u ulaz pecine i na kraju može da formira led koji je grubo kristalni –slican ledniku t.j. gleceru. Pravi podzemni gleceri su rjetki.
Ledene formacije – Voda koja se zaledi prije sakupljanja može da formira ledenice, ledene stalagmite, ledene stubove i zamrznute vodopade.
Vlaga vazduga (vodena para) - Zamrzavanje pare može formirati ledene kristale, inje ili tzv. "zamrznuto perje", dvodimenzionalne ledene ploce po zidovima i na vrhu (plafonu) pecina.
Ledene iglice – infiltrirana voda koja se zamrzava u temelju ponekad može biti utjerana (prinudena da ude) u pecinski prolaz.
Intruzija – Težina površinskog glecera koji je smješten na vrhu ulaza u pecinu može na kratkim rastojanjima silom pribiti glacijalni led u pecinu. Jedini poznati primjeri ovog fenomena su ledeni cepovi u zadnjem dijelu Castleguard pecine u Alberti.
Kako da prijavite k cache?
Za prihvatanje vašeg loga pošaljite odgovore na sljedeca pitanja putem našeg profila:
1) Kakve ledene formacije ste mogli posmatrati u pecini?
2) Koji tip temperaturnog mehanizma se stvorio u ovoj pecini?
Opciono, molimo vas da dodate licnu fotografiju i vaše GPS koordinate PRIJE u pecini. (Fotografija nije uslov za odobravanje loga).
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Molimo vas da ponesete vaše odpatke sa sobom iz Ledene Pecine i tako pripomognete u održavanju njene cistoce.