Modelling of slope processes on karst

Abstract

Izvleček UDK 911.2:551.435(497.471) Uroš Stepišnik & Gregor Kosec: Modeliranje pobočnih pro� cesov na krasu Članek obravnava modeliranje pobočnih procesov na krasu. Predstavljen je preprost enodimenzionalen fizikalni model preko katerega se oceni temeljno obnašanje pobočnih procesov. Model upošteva masno kontinuiteto prepereline ter mehanično in kemično preperevanje matične kamnine. Članek podrobneje obravnava oblikovanje pobočij pri različnih intenzivnostih prevladujočih procesov (mehansko in kemično preperevanje ter pobočni procesi). Uporabljen pristop predstavlja prvi korak k razumevanju pobočnih procesov, vendar ne vsebuje primerjav z realnimi terenskimi meritvami. Podatki pridobljeni s predstavljenim modelom kažejo dobro kvalitativno ujemanje s terenskimi opazovanji. Podrobneje so predstavljeni trije tipični primeri: primer prevladujočega mehanskega preperevanja, primer uravnoteženega mehanskega in kemičnega preperevanja ter primer prevladujočega kemičnega preperevanja.

Periodically inundated uvalas and collapse dolines of Upper Pivka, Slovenia

“…Topography and orientation of those depressions are largely affected by local geologic structure. Their slopes are covered by karren and balanced (Stepišnik and Kosec 2011;Godard et al 2016) while floors are covered by thicker layer of regolith. Floors that are periodically inundated are partially levelled by fine grained loamy deposits.…”

“…Most of the hollows have well expressed boundaries between slopes and surrounding karst plain. Their slopes are regularly steep, rocky and active (Stepišnik and Kosec 2011;Godard et al 2016). Scree and boulders regularly cover lower sections of these slopes.…”

“…The floor's transit to the western and northern slopes is very gradual. These slopes are fully balanced (Stepišnik and Kosec 2011). Regular inundation of this depression extends to an altitude of 562 m. At extremely high levels of karst waters, the elevation of the floods reaches up to ~568 m (Kovačič and Habič 2005).…”

“…Almost all of the slopes are active, partly consist of steep rocky walls with collapse blocks below them. Only a part of the eastern slope is balanced (Stepišnik and Kosec 2011). Intermittent inundations within the Veliko Zagorsko Jezero depression reach elevations of 550 m, during extreme watertable levels even 551 m (Habič 2005 ERT profile of Veliko Zagorsko Jezero was measured from western slopes at an elevation of ~556 m towards the central part of the flattened floor (azimuth of profile: 115 degrees).…”

“…The width of the floor is ~70 m and the length is ~100 m. Within the central part of the floor two suffusion dolines are formed. Levelled floor sharply transits into surrounding slopes that are active (Stepišnik and Kosec 2011). Parts of the north-eastern slopes are rocky walls with scree and collapse blocks below them.…”