The effect of Quaternary uplift on the stability of slopes in the central part the Skorusinske Vrchy mountains in the west Carpathians

Abstract

Abstract The Skorušinské vrchy mountains are part of the West Carpathians in northwest Slovakia near the Polish border. They consist of four Palaeogene sedimentary complexes and comprise a 1500 to 2000 m thick sequence of conglomerates, claystones, flyschoid rocks and sandstones. The older complexes erop out on the margins of the mountains and are covered by relatively thin clayey soils. The central part, the most highly uplifted block, consists of Eocene calcareous sandstone which are disturbed by joints and deep-seated faults. The difference in elevation between the mountain summits and the valley floors is more than 400 m. A detailed investigation of mass movement has been carried out using aerial photographs,air borne radar and satellite imagery foliowed by a field survey. Three main types of slope deformation were identified - rock block slides along bedding surfaces, rock siumps across bedding surfaces and landslides in slope debris. The occurrence of the largest and most deep-seated slides are controlled by faults. The presence of these mass deformations indicate the existence of tilted fault blocks which are the result of neotectonic arch uplift. About 15–17% of the area covered by sandstones is affected by mass movements. This paper describes the methodology of the investigation, the mechanism and genesis of slope deformations, the occurrence and parameters of slides and the role of the Quaternary uplift in the slope instability component of regional geomorphological evolution.