engleski

Explorations and Geomorphology of the Velebita Pit on the North Velebit Mt. in Croatia - World`s Deepest subterranean Shaft

The northern Velebit massif according to the recent exploration results is speleologicaly the most important Dinaric karst region. In the last 14 years about 300 caves were discovered and explored. The system Lukina jama - Trojama (-1392 m) and Slovačka jama (-1301 m) are the deepest caves in Croatia and rank 16th and 21st deepest caves in the world. Furthermore, significant depths were reached in the Meduza (-679 m), Patkov gušt (-553 m), Ledena jama (-536 m) and Jama Olimp (-531 m) caves. The karstification processes are dominantly controlled by vertical groundwater circulation through the deep unsaturated zone built up of fractured carbonate rocks. As the result about 97 % of explored caves may be classified as pits with long vertical sections as their major morphological characteristic. For instance, the 553 m deep pit Patkov gušt practically consists of one vertical shaft, the final part of Meduza represents a 390 m deep vertical shaft. Vertical sections longer than 200 m can be found in almost all deeper caves. The intense vertical karstification processes and genesis of extremely deep speleologic objects in this area are confirmed by the last explorations in the Velebita pit. This 580 m deep cave system morphologically has 513 m subterranean (internal) vertical section, which is the world’ s deepest subterranean shaft.

karst hydrogeology; speleogenesis; speleomorphology

nije evidentirano