Karstbase Bibliography Database
Karstbase Bibliography Database
In geomorphogenesis of the fore-mountain region, a leading role is played by the processes of dismemberment of «shielding» limestone layers of the monoclinal stratified structure, and slope processes in the intervals of rocky limestone utcrops. Their main pre-condition for the latter is hypogene karst development which preceded the modern relief and controlled its formation. Karstified fracture-karst zones, 100 to 400 m wide, in the Cretaceous-Paleogene strata controlled the entrenchment of valleys in the limestone layers. The basic elements of hypogenic karst structures, which forms their spatial framework, are subvertical
fracture-karst conduits (karst «rifts»). Dissection of limestone layers along vertical fracture-karst rift conduits initially set the cliff-like shape of valleys slopes, and presence of such rift conduits in the rear of cliffs of already incised valleys determines the mechanisms of cliff retreat, with the maintenance of verticality, and controls position and configuration of segments of cliffs. A dominant slope process in the intervals of limestones is block toppling, whereas blocks become separated mainly along remaining
fracture-karst conduits in rearward parts of cliffs. Hypogenic sculptural morphology is displayed in the exposed walls of the fracture-karst conduits, which determines the originality and nomenclature of morphology of limestone cliffs of the Inner Range. In those areas of slopes where position of cliffs has stabilized for considerable time due to absence of new lines of block detachment in the rear, weathering becomes a significant process in the morphogenesis of surfaces. Slopes lose their verticality and acquire
the smoothed rims. Specific hypogenic sculptural morphology of cliffs is being destroyed on such slopes. The finding about control of slope processes in limestones by hypogenic fracture-karst structures gives new important criteria for the slope condition assessment and prognosis of hazardous collapses and rockfalls in the limits of the Internal Range