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Vrelo Bune/Buna Spring EarthCache

Hidden : 07/19/2015
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Geocache Description:

ENG: Let me invite you to the one of the most precious and unique sites in Bosnia and Hercegovina. To Vrelo Bune. :)

BIH: Dozvolite mi da vas pozivam u jedan od najdragocjenijih i jedinstvenih lokaliteta u Bosni i Hercegovini. U Vrelo Bune. :)


On 11/12/2007 it has been submitted to UNESCO and is registered on the World Heritage Tentative List ref. 5280 the ensemble of Blagaj.

It is impossible to discuss the cultural and historical heritage of Blagaj without also considering its natural values. Blagaj is a rich natural area, with varied contours, morphologically fascinating, with a pleasant Mediterranean climate of mild winters. In a relatively small area one can find both pronounced karst forms with steep slopes (Blagaj hill, Stjepan grad) but also level or gently sloping valleys and river banks. The river Buna, though short, with its outstandingly clear water of high quality, is the habitat of a great many rare and endemic fauna species of world ranking (the soft-lipped trout, the nose carp, and the marble trout). This region is specific for the diversity of its above-ground and underground hydrographs.

The source of the Buna is the finest example of an underground karst river, one of the largest and most beautiful in Europe. According to the nomination for the list of national monuments in Bosnia and Herzegovina the source of the Buna River with its cliffs constitutes a geomorphological natural monument and hydrological natural monument.


The Buna is a short river; it is a left bank tributary of the Neretva River. Its source (Vrelo Bune), a strong karstic spring, is near the village Blagaj, about 12 km southeast of Mostar. It appears at the altitude of 64 meters above the sea-level. The Buna flows west for approximately 9 km, starts at Blagaj and meandering through villages Blagaj, Kosor, Malo Polje, Hodbina and joins the Neretva at Buna village. The Bunica River is main left bank tributary of the Buna. French speleologists explored the underground length of the Buna River for two hundred meters. Colour of the water is blue – emerald green, obviously affected by calcium-carbonates solution. The average annual source production is 43 m3 of the water per second. It may fall down to 2 m3 during the very dry summer time. Above today’s cavern of the water source, there are few older cavities, which prove the karstic origins of the spring. Temperature of the Buna water never raises over 18°C; however the lowest measured temperature was 2°C in 1954 and the highest measured was 19°C in 1950. The average usually stays around 10°C.

The first thing that you can notice in the overall scenery is the strong karstic spring coming from the karstic cavern beneath 250 meters high vertical stone cliff immediately into a powerful river with clean and pretty cold water.

And for sure, you’ll never miss the architectural ensemble which stands beside the spring – the Blagaj Trekke. The historical Blagaj Trekke is a Sufi monastery built around 1520 by the dervishes from Anatolia with a design that features the mixture of Ottoman and Mediterranean architecture. The monastery’s guest house called musafirhana was built in 1664 and rebuilt in 1851, close to the site’s natural surroundings, making it look like it naturally carved from the cliff face. Today it represents one of the most mystical places in Bosnia and Herzegovina and it is opened for visitors throughout the year.


Karst topography is a landscape 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 weathering-resistant rocks, such as quartzite, given the right conditions. Subterranean drainage may limit surface water with few to no rivers or lakes.

The development of karst occurs whenever acidic water starts to break down the surface of bedrock near its cracks, or bedding planes. As the bedrock (like limestone or dolostone) continues to break down, its cracks tend to get bigger. As time goes on, these fractures will become wider, and eventually, a drainage system of some sort may start to form underneath. If this underground drainage system does form, it will speed up the development of karst arrangements there. This increase in rate of karst feature development will be due to the fact that more water will be able to flow through the region. Beneath the surface, complex underground drainage systems (such as karst aquifers) and extensive caves and cavern systems may form.


Types of Weathering

Mechanical/physical weathering - physical disintegration of a rock into smaller fragments, each with the same properties as the original. Mainly occurs by temperature and pressure changes. Frost Wedging - water expands when it freezes. Thermal Expansion and Contraction - heating causes rock to expand, cooling results in contraction; different minerals expand and contract at different rates. Mechanical Exfoliation - rock breaks apart in layers that are parallel to the earth's surface; as rock is uncovered, it expands (due to the lower confining pressure) resulting in exfoliation. Abrasion - physical grinding of rock fragments.

Chemical weathering - process by which the internal structure of a mineral is altered by the addition or removal of elements. Change in phase (mineral type) and composition are due to the action of chemical agents. Chemical weathering is dependent on available surface for reaction temperature and presence of chemically active fluids. Smaller particle sizes weather by chemical means more rapidly than large particles due to an increase of surface area.

And we can mention the biological weathering as well. Living organisms contribute to the weathering process in many ways. Trees put down roots through joints or cracks in the rock in order to find moisture. As the tree grows, the roots gradually prize the rock apart. Many animals bore into rocks for protection either by scraping away the grains or secreting acid to dissolve the rock. Even the tiniest bacteria, algae and lichens produce chemicals that help break down the rock on which they live, so they can get the nutrients they need.

All these processes may act independently, but will more often than not, occur simultaneously. Different circumstance will have one weathering process more important than another.

Chemical Weathering

Let’s talk a bit more about the chemical weathering. It occurs when rocks which formed deep underground are exposed to environmental conditions at the Earth's surface. Chemical reactions occur to bring them back into equilibrium with their surroundings, which often weakens their structure and rigidity, causing them to disintegrate. Chemical reactions in general happen when something is out of equilibrium with its surrounding environment. Chemical weathering is the process where rocks and minerals, which originally formed deep underground at much higher temperatures and pressures, gradually transform into different chemical compounds once they are exposed to air and water at the surface. The farther out of equilibrium a particular mineral is, the faster it will weather. In general, the new chemical forms are structurally weaker than the original rock, which causes the rock to eventually disintegrate. Chemical weathering is caused by rain water reacting with the mineral grains in rocks to form new minerals (clays) and soluble salts. These reactions occur particularly when the water is slightly acidic. These chemical processes need water, and occur more rapidly at higher temperature, so warm, damp climates are best. Chemical weathering (especially hydrolysis and oxidation) is the first stage in the production of soils. Weathering rates depend on the composition of the rock, temperature range and rainfall amount. Weathering produces soils. Soils may or may not remain in place, and any soil may be a combination of residual and transported material.

Factors Affecting Chemical Weathering are the Mineral Composition, the Soil/Vegetation Cover, the Climate, the Relief and the Human Activity.

Types of Chemical Weathering

There are three basic types of chemical reactions that cause four types of chemical weathering of rocks. Dissolution and hydrolysis are caused by reactions with acids. Hydration is the absorption of water. Oxidation is reaction with oxygen.

1. Acid Reactions

Acids are chemical compounds that produce H+ ions when dissolved in water. The stronger the acid, the more H+ ions they produce. Acids can react with any rock mineral that has other positive ions, like Ca++, Na+, or K+, by taking their place - which changes the chemical composition of the mineral and disrupts its atomic structure. The most important natural acid is carbonic acid (H2CO3), which forms from carbon dioxide and water (CO2and H2O). Others include sulphuric acid (H2SO4) and hydrofluoric acid (HF) which mainly come from volcanic eruptions.

In hydrolysis, silicate and carbonate minerals transform into new minerals, principally clay minerals which have a sheet like structure similar to mica. Both the chemical composition and crystalline structure become completely different. Hydrolysis takes place when acid rain reacts with rock-forming minerals such as feldspar to produce clay and salts that are removed in solution. The only common rock-forming mineral that is not affected is quartz, which is a chemically resistant mineral. This is why quartz and clay are the two of the most common minerals in sedimentary rocks.

In dissolution, the acid completely dissolves the original rock, leaving nothing solid behind. For example, the gradual action of carbonic acid on limestone (main mineral: calcite, or CaCO3) over a very long time span is responsible for all of the world's spectacular limestone caves.

Solution happens by removal of rock in solution by acidic rainwater. In particular, limestone is weathered by rainwater containing dissolved CO2, (this process is sometimes called carbonation).

Carbonation comes meanwhile when carbon dioxide in the air dissolves in rainwater and becomes weakly acidic. This weak “carbonic acid” is able to dissolve limestone as it seeps into cracks and cavities. Over many years, solution of the rock can form spectacular cave systems. Note: Stalagmites and stalactites form in caves as water drips from the roof, depositing some of its dissolved calcium carbonate, as carbon dioxide is released into the air.

Acid rain appears, when polluting gases, like sulphur dioxide and nitrogen oxide dissolve in rainwater to make stronger acids. When this rainwater falls, we get acid rain. This acid attacks many rock types, both by solution and hydrolysis, seriously damaging buildings and monuments.

2. Hydration

The term ‘hydration’ refers to the absorption of water. The H+ and OH- ions of water incorporate themselves into the atomic structure of a mineral to form a new version of it called a hydrate. If the original mineral had a chemical formula of X, the new suite of minerals will have chemical formulas of X. nH2O. For example, anhydrite (CaSO4) exposed to water hydrates into gypsum (CaSO4. 2H2O).

3. Oxidation

Oxidation is where oxygen from the atmosphere reacts with metal elements in the rocks to form oxides. The most common metal involved is iron. It reacts with oxygen to form iron oxide minerals such as hematite (Fe2O3) or, if water is present which it often is, hydration occurs in conjunction to form limonite (Fe2O3 .nH2O). Oxide minerals tend to be structurally weak and easily crumbled.

Logging Requirements

To log this Earthcache, you have to answer the following questions correctly and to send them to the owner (via the GC profile function to mailbox You don't need to wait for the owner's approval! However the simultaneous log and email in a real time are awaited. Obviously false logs without proved presence on the site will be deleted without prior warning. But don't worry, humans make mistakes... :)


  1. What affects the colour of the Buna water? (listing)
  2. Name three aspects on which chemical weathering rates depend. (listing)
  3. Name all four types of chemical weathering. (listing)
  4. According to your observation, how many older spring cavities can you see above today’s cavern of the water source? (on the spot)
  5. What is your estimation, how high and how wide in meters is visible mouth of today’s cavern of the water source? Be careful, most of the Internet sources are not precise! (on the spot)


  1. Any photo posted with your log, which showed the ACTUAL WATER LEVEL, would be more than appreciated. NO NEED FOR PERSONS BEING ON THE PHOTO. (on the spot)

Good luck and enjoy the place! :)


U 11/12/2007 je bila dostavljena UNESCO-u je registrirana na Tentativnu listu svjetske baštine ref. 5280 cijelina Blagaj.

Nemoguće je da se razgovara o kulturno-povijesne baštine Blagaja bez također s obzirom na prirodne vrijednosti. Blagaj je bogato prirodno područje, sa različitim konturama, morfološki fascinantno, s ugodnom mediteranskom klimom blagih zima. U relativno malom prostoru se mogu naći i izreći kraških oblika sa strmim padinama (Blagaj brdo, Stjepan grad), ali i razinu ili blago nagnut kotlinama i uz riječne banaka. Rijeka Buna, iako kratka, sa izuzetno čistom vodom visoke kvalitete, je stanište velikog broja rijetkih i endemskih životinjskih vrsta u svijetu rangiranja (soft-usana pastrmka, šaran nos, a glavatice). Ova regija je specifična za raznolikost svojih nadzemnih i podzemnih hidrografa.

Izvor Bune je najbolji primjer podzemnih kraških rijeka, jedan od najvećih i najljepših u Europi. Prema nominaciju za listu nacionalnih spomenika u Bosni i Hercegovini izvor rijeke Bune sa liticama predstavlja geomorfološki spomenik prirode i hidrološki spomenik prirode.


Buna je kratka rijeka; ona je lijeva pritoka rijeke Neretve. Njen izvor (Vrelo Bune), snažan kraških izvora, je u blizini sela Blagaja, oko 12 km jugoistočno od Mostara. Čini se na nadmorskoj visini od 64 metara iznad nivoa mora. Buna teče na zapad za oko 9 km, počinje u Blagaju i vijugaje kroz sela Blagaj, Kosor, Malo Polje, Hodbina i pridružuje Neretve kod sela Buna. Rijeka Bunica je glavni lijevoj pritok rijeke Bune. Francuski speleolozi istražili su podzemni dužin rijeke Bune za dvije stotine metara. Boja vode je plava - smaragdno zelena, očito uječena otapanjem kalcijum-karbonata. Prosječna godišnja proizvodnja izvora je 43 m3 vode u sekundi. To može pasti do 2 m3 u vremena vrlo suhoh ljeta. Iznad današnjeg pećini izvora vode, postoji nekoliko starijih šupljina, kojima se dokazuje kraško poreklo izvora. Temperatura vode Bune nikada ne podiže iznad 18 ° C; Međutim najniža izmjerena temperatura je 2 ° C u 1954. godine i najviša izmjerena je 19 ° C u 1950. Prosječna obično ostaje oko 10 ° C.

Prva stvar koju možete primjetiti je jaki kraški izvor, koji dolazi iz kraških pećina ispod 250 metara visoke litice vertikalna kamena odmah u moćnu reku sa čistim i prilično hladnom vodom.

I sigurno, nikada nećete propustiti graditeljska cjelina koja stoji pored proljeće - Blagajska Tekija . Istorijska Blagajska Tekija je manastir Sufi izgrađen 1520. od derviša iz Anadolije s dizajnom koji sadrži mješavinu osmanske i mediteranske arhitekture. Manastira gost kuća se zove musafirhana je izgrađena 1664. godine, a obnovljena 1851. godine, u neposrednoj blizini prirodnog okruženja sajta, što ga čini da izgleda kao da prirodno isklesa iz litice. Danas predstavlja jedan od najvažnijih mističnog mjesta u Bosni i Hercegovini i to je otvoren za posjetitelje tijekom cijele godine.


Kraška topografija je pejzaž formiran od raspada topljivih stijena poput vapnenca, dolomita, i gipsa. Odlikuje se podzemnu odvodnju sistema sa jame i pećine. Podzemna drenaža može ograničiti površinske vode s malo ili nimalo rijeka ili jezera.

Razvoj krša nastaje kad god kisele vode počinje da razbije površinu kamen temeljac u blizini svoje pukotine, ili osnovnih sloja. Kao temelj (poput vapnenca ili dolomitske) nastavlja da razbiju, svoje pukotine imaju tendenciju da se veći. Kako vrijeme prolazi, ovi prelomi će postati šire, i na kraju, a sustav odvodnje od neke vrste mogu početi da se formira ispod. Ako se ovaj podzemni sustav odvodnje radi forme, to će ubrzati razvoj krša aranžmana tamo. Ovo povećanje stope krša razvoj će biti s obzirom na to da će više vode moći da teče kroz regiju. Ispod površine, kompleks podzemnih drenažnih sistema (kao što su kraške izdani) i opsežne pećina i pećina sistema može formirati.


Vrste atmosferskog djejstva na stjenje

Mehaničko/fizička djejstva - fizički raspada se kamen u manje fragmente, svaki sa istim svojstvima kao i original. Uglavnom se javlja temperature i tlaka promjene. Klinovanje ljeda - voda širi kada se ledi. Toplinskog širenja i skupljanja - grijanje uzrokuje rok za proširenje, rezultati hlađenje u kontrakciji; različitih minerala proširiti i ugovor na različitim stopama. Mehanički piling - kamen raspao se u slojevima koji su paralelno sa površine zemlje; kao stijena je otkriveno, i širi (zbog nižih serklaže pritisak) dovodi do piling. Abrazija - fizički brušenje kamenje.

Hemijska djejstva - proces kojim unutrašnju strukturu minerala menja dodavanjem ili uklanjanjem elemenata. Promjena u fazi (mineralnog tipa) i sastav su zbog djelovanja kemijskih agenasa. Kemijska djejstva ovisi u površini na raspolaganju za temperaturu reakcije i prisustvo hemijski aktivnih tečnosti.

I možemo isto tako spomenuti biološka djestva. Živi organizmi doprinose procesu atmosferskig djejstva na stijenje na mnogo načina. Drveće spusti korijene kroz fuge ili pukotine u stijeni kako bi se pronašli vlage. Kao stablo raste, korijene postepeno razbija kamen. Mnoge životinje nosio u stijenama za zaštitu bilo struganje zrna ili luči kiselina da raspusti kamen. Čak i najmanja bakterija, algi i lišajeva proizvesti kemikalije koje pomažu razbiti stijene na kojoj žive, tako da oni mogu dobiti hranjive tvari koje su im potrebne.

Svi ovi procesi mogu djelovati samostalno, ali će češće nego ne, javljaju istovremeno. Različiti okolnost će imati jedan vremenski proces važniji od drugog.

Hemijska atmosferska djejstva na stijenje

Porazgovarajmo malo više o hemijskim djejstvu. To se događa kada stijene koje su činile duboko pod zemljom su izloženi životne uvjete na Zemljinoj površini. Hemijske reakcije javljaju da ih vrati u ravnoteži sa svojim okruženjem, koje često slabi njihovu strukturu i čvrstinu, nanoseći im da se raspada. Hemijske reakcije općenito se dogoditi kada nešto nije u ravnoteži sa svojim okruženjem. Hemijsko atmosfersko djejstvo je proces gdje kamenje i minerale, koji je prvobitno formiran duboko pod zemljom po znatno višim temperaturama i pritiscima, postepeno transformiše u različite kemijske spojeve nakon što su izloženi u zrak i vode na površini. Na dalje od ravnoteže određeni mineral je, to će brže vrijeme. U principu, novi kemijske forme su strukturalno slabije od originala stijena, što dovodi do toga da rok da na kraju se raspada. Kemijski na vremenske je uzrokovana kišnice reagira s mineralnom zrna u stijenama za formiranje nove minerale (glina) i topivih soli. Ove reakcije se javljaju posebno kada je voda blago kisela. Ovi hemijskih procesa potrebna voda, i brže se javljaju na višim temperaturama, tako toplo, vlažno klimama su najbolji. Hemijsko atmosfersko djejstvo na stijenje (posebno hidroliza i oksidacija) je prva faza u proizvodnji zemljišta. Mjere hemijskih atmosferskih djejstva na stijenje zavisa na sastavu stijena, raspon temperatura i količina padavina. Vremenske uslove proizvodi zemljišta. Zemljišta može ili ne mora ostati na mjestu, a bilo tlo može biti kombinacija zaostalih i transportuje materijala.

Faktora koji utiču na hemijska atmosferska djejstva na stijenje su mineralni sastav, tlo/vegetacijskog pokrivača, klima, reljefa i ljudske aktivnosti.

Vrste hemijskog atmosferskog djejstva na stijenje

Postoje tri osnovne vrste hemijskih reakcija koje uzrokuju četiri vrste hemijskog atmosferskog djejstva na stijenje. Raspuštanje i hidrolize su uzrokovane reakcije sa kiselinama. Hidratacija je apsorpcija vode. Oksidacija je reakcija s kisikom.

1. Kiselinske reakcije

Kiseline su hemijska jedinjenja koja proizvode H + ioni kada otopljen u vodi. Što je jača kiselina, više H + ioni ona proizvodi. Kiseline može reagirati s bilo rock mineral koji ima i druge pozitivne ione, kao što su Ca ++, Na +, K + ili, uzimajući svoje mjesto - koji mijenja kemijski sastav mineralnih i remeti njene atomske strukture. Najvažnija prirodna kiselina je ugljena kiselina (H2CO3), koja je sastavni od ugljen-dioksida i vode (CO2and H2O). Ostale su sumporna kiselina (H2SO4) i fluorovodonična kiselina (HF) koji uglavnom dolaze iz vulkanskih erupcija.

U hidrolize, silikatna i karbonatna minerala pretvaraju u nove minerale, uglavnom minerala glina koji imaju list kao što je struktura slična mica. Oba kemijski sastav i kristalne strukture postaju potpuno drugačiji. Hidroliza mjesto kada kisele kiše reagiraju s mineralama formirajučima kamen kao što su feldspat za proizvodnju gline i soli koje su uklonjene u otopini. Jedin zajednički mineral formirajuči kamen koji se ne utiče je kvarc, koji je hemijski otporan mineral. To je razlog zašto kvarca i gline su dva od najčešćih minerala u sedimentnim stijenama.

U raspuštanja, kiselina potpuno rastvara originalni kamen, ostavljajući za sobom ništa solidno. Na primjer, postepeno akcija ugljene kiseline na vapnenca (glavni mineralna: kalcit, ili CaCO3) preko vrlo dugo vremena trajanja je odgovoran za sve spektakularne svjetske kraške pećine..

Raspuštanje se događa po uklanjanje stijena u otopini kiselim kišnicom. Konkretno, krečnjak je prebrodio od kiše koja sadrži otopljenog CO2, (ovaj proces se ponekad naziva karbonizacija).

Karbonizacija dolazi u međuvremenu kada ugljičnog dioksida u zraku rastvara u kišnicu i postaje slabo kisele. Ova slaba "ugljene kiseline" je u mogućnosti da raspusti krečnjak kao što procuri u pukotine i šupljine. Preko mnogo godina, raspuštanje stijene mogu formirati spektakularan sistem pećina. Napomena: Stalagmiti i stalaktita se formiraju u pećinama, kao voda kaplje s krova, deponovanja neke od svojih rastvorenih kalcijum karbonat, kao ugljen-dioksid se ispušta u zrak.

Kisele kiše se pojavljaju, kada štetnih gasova, kao što su sumpor-dioksida i dušičnih oksida rastvaraju u kišnicu da jače kiseline. Kada se to kišnica padne, dobijamo kisele kiše. Ovaj kiselina napada mnoge vrste stijena, kako od strane raspuštanja i hidrolize, ozbiljno oštećenje zgrade i spomenike.

2. Hidratacija

Izraz "hidratacija“ se odnosi na apsorpciju vode. H + i OH- ione vode ugraditi sebe u atomsku strukturu minerala da formira novu verziju je to nazvao hidrat. Ako originalni mineral ima kemijske formule X, novi paket minerala će imati kemijske formule X. nH2O. Na primjer, anhidrida (CaSO4) izložen vodi hidrata u gips (CaSO4. 2H2O).

3. Oksidacija

Oksidacija je gdje kisik iz atmosfere reagira sa metalnim elementima u stijenama za formiranja oksida. Najčešći metal uključeni je željezo. On reagira s kisikom da se formiraju željezni oksid minerala kao što su hematita (Fe2O3) ili, ako je prisutan koji često je voda, hidratacija javlja zajedno da se formira limonit (Fe2O3 .nH2O). Oksid minerala imaju tendenciju da budu strukturno slabe i lako raspadajuče.

Zapisni uslovi

Da biste se zapisali ovaj Earthcache, morate ispravno odgovoriti na sljedeća pitanja i poslati ih vlasniku (putem GC profil funkciju na govornu poštu Ne morate čekati na odobrenje vlasnika! Međutim, istovremeni zapis i e-mail u realnom vremenu se čeka. Očigledno lažni zapisi bez dokazane prisutnosti na sajtu ću biti izbrisani bez prethodnog upozorenja. Ali, ne brinite, ljudi čine greške ... :)


  1. Što utječe na boju Bune vode? (spisak)
  2. Napiši tri aspekta na kojih zavisa mjere hemijskih atmosferskih djejstva na stijenje. (spisak)
  3. Napiši sve četiri vrste hemijskih atmosferskih djejstva na stijenje. (spisak)
  4. Prema tvog zapažanja, koliko postoji starjih šupljina iznad današnjej pećini izvora vode? (na licu mjesta)
  5. U tvoj procjeni, koliko visoka i koliko široka jesu u metrima vidljiva usta današnje pećine izvora vode? Budi oprezan, većina internet izvora nisu precizni! (na licu mjesta)

Po želji:

  1. Bilo koja slika objavljena sa tvojim zapisom, koja pokazuje aktuelno stanje visine vode, bila bi više nego dobrodošla. NEMA POTREBE ZA LICA NA SLICI. (na licu mjesta)

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