Geological Conditions - Factor of Origin of Two Different Cave Systems in Two Adjacent Valleys (the DemäŠnovskᇠValley and the J‡ánska Valley, the Low Tatras, Slovakia)

Abstract

Demänovská dolina ja najznamenitejša kraška dolina v severnem pobočju Nizkih Tater. V dolini je poznan 30 km dolg jamski splet Demänovská jama. Podobna je sosednja, Jánska dolina, v kateri je ducat jam, ki skupno merijo preko 30km. Morfološki in hidrološki pogoji v obeh dolinah so podobni, jamski sistemi pa močno različni. Demänovská jama je v celoti razvita na vzhodni strani Demänovske doline, medtem ko so jame v Jánski dolini razvite na obeh straneh te doline. Demänovska jama jo enoten, vseskozi prehoden jamski sistem, medtem ko sistem jam v Jánski dolini med seboj ni povezan s prehodnimi rovi. Oba jamska sistema sta razvita v gutensteinskih apnencih. Avtor pipisuje razliko med jamami v obeh dolinah različnim strukturno geološkim pogojem. Demänovská dolina leži v območju monoklinale Krížňanskega pokrova, Jánska dolina pa v območju ChoËskega pokrova z zelo zapleteno tektonsko zgradbo

The Demänovská Valley is the most famous karst valley in the northern slopes of the Low Tatras. There the DemänovskáCave system is developed more than 30 km long. The similar karst valley, the Jánska Valley with dozens of underground karst phenomena is situated ten kilometers to the east. The total length of these caves exceeds 30 km. The geomorphological, hydrological, and karst conditions of these two valleys are similar; nevertheless there are several outstanding differencies between two cave systems developed in them. The whole of the Demänovská Cave system is developed within the eastern slope of the DemänovskáValley. On the contrary in the Jánska Valley significant caves are situated on both sides of the valley. Besides this difference the Demänovská Cave system is penetrable through the whole of its length whereas cave system of the Jánska Valley is not penetrable although connection of the underground spaces was proved by various methods. The described state is caused by different geological conditions in these valleys. Both cave systems are developed mostly in the Middle Triassic Gutenstein Limestones. But the Demänovská Valley is situated in the area which is built by monocline of the Krížňanský nappe. In the territory of the Jánska Valley there is the Chočský nappe which is tectonically very complicatedly framed.