Naslov
Longest and deepest caves of Dinaric karst: 25 years of speleological research of Velebit Mt, Croatia

Autori
Bakšić, Darko ; Paar, Dalibor ; Stroj, Andrej ; Lacković, Damir ; Barišić, Teo

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
23rd International karstological school "Classical karst" Caves - Exploration and Studies / Hajna, Nadja Zupan ; Mihevc, Andrej ; Gostinčar, Petra - Postojna : Karst Research Institute - ZRC SAZU, 2015, 93-94

ISBN
978-961-254-808-7

Skup
23rd International karstological school "Classical karst" Caves - Exploration and Studies

Mjesto i datum
Postojna, Slovenija, 15.06.2015. - 19.06.2015

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Dinaric karst; caves
(Dinarski krš; špilje)

Sažetak
We shall present story about discoveries and explorations of the deepest and longest Caves currently known in both Croatia and entire Dinaric Karst region. These caves comprise three caves deeper than 1km and 27, 8 km long Kita Gaćešina cave system, all situated within the Velebit mountain range.. Velebit mountain range, with its 145 km in length, is the longest Croatian mountain. The area of Northern Velebit, where the deepest caves are situated, is composed almost entirely of carbonate rocks ranging from Middle Triassic to Paleogene Age.. The largest part of Northern Velebit is composed of Jurassic carbonates (>2, 5 km m thick), predominantly limestones. Specific properties of strongly karstified Oligocene to Miocene tectogenic carbonate breccias also play significant role in morphology and speleogenesis of the caves. Speleological explorations have revealed a complex geology of Northern Velebit through determined occurances of the breccias to great depths. For example, in Lukina Jama Cave System (depth 1431 m) these breccias are prevailing to the depth of – 950 m, but appear in alteration with bedded Jurassic rocks from -250 m. A similar situation occurs in Slovačka Jama (depth 1320 m) as well. This poses a number of questions related to their genesis and stratigraphy.. In almost 25 years of exploration, only in Northern Velebit area 348 caves were explored, 3 deeper than 1000 m, 5 deeper than 500 m. Basic morphological features of Velebit caves are verticality and the incidence of major verticals with absence of horizontal passages. The biggest discovered verticals are located in Patkov gušt (P553), Cave systemVelebita (P513), Meduza (P333) and in Cave system Lukina jama (P329). Five verticals are deeper than 200 m and 100 m verticals are quite common. The majority of Croatian caving associations participated in the cave research but the most of those expeditions were organized by the Speleological Committee of Croatian Mountaineering Association. During all these years of research an excellent international cooperation was formed with cavers from many European countries and USA. The longest presently known Cave in the Dinaric karst, Kita Gaćešina Cave System is situated in the Crnopac Massif on the southernmost part of the Velebit mountain range. Geologically massif is composed of Oligocene and Lower Miocene carbonate breccias in its central parts, surrounded and underlain by Jurassic limestones, similar to the previously described North Velebit area.In contrast to the North Velebit, polygenetic multilevel caves are here descovered, probably due to the long history of water flow from higher Lika region to the Zrmanja river valley through the subterranean passages in the massif. Speleogenesis of the caves in the Crnopac Massif probably have lasted continuously from the beginning of the massif uplift (upper Miocene). Mechanical properties of the carbonate breccias play a significant role in the cave morphology. Mechanical stability due to the low frequency of cracks and joints in these massive breccias enables the preservation of underground passages and chambers of very large dimensions. In more than 10 years of intensive research Cave system of Kita Gaćešina – Drazenova puhaljka reached the length of 27, 802 m, depth of 737 m and became the Croatian and Dinaric karst longest cave. Speleological exploration is still not close to the end. Nearby cave Munižaba (9 715 m long and 510 m deep) is one with biggest underground spaces in Croatian part of Dinaric karst.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

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