Veress Márton: A Bakony természettudományi kutatásának eredményei 23. - Covered karst evolution... (Zirc, 2000)

METHODS

more or less uniform rate of denudation, this was the case too when karst water table was close to the present-day surface.) The standard deviation of the longer axes of collapse dolines has been studied statistically. Minimum standard deviation (S=0,67) was found for narrow collapse dolines, followed by the value for wide collapse dolines (S=0,83) and for the circular collapse dolines (S=l,27). The above distributions can be interpreted in the following manner. Closer to the rock boundary, where karst water flow is horizontal, theoretically the current can take any direction. Therefore, the cavities formed by the current may have variable alignments. Away from the rock boundary the more and more vertical movement follows the fracture pattern of the nummulitic limestone. Thus, the alignments of cavities are controlled by fracture lines. Cavitation along fractures cannot produce such a wide range of fracture alignments. Laboratory analyses The material deposited in flood ponds on the plants of karstic depressions was analysed and found to be colloids. Sedimentation in flood ponds was modelled. It was investigated how the coarser (hair) and finer (foam) materials deposit on the sides and floors of basins during water subsidence of uniform, growing or changeable rate. Theoretical approaches The methods and laws described in the literature on karst were applied to the covered karst and karstification of the mountains. - The role of rock boundary in karstification was investigated by JAKUCS (1956, 1971a). Author introduced the concept of hidden rock boundary which marks those sites on covered karst where the thinning out of cover sediments allows karstification. - The term bathycapture was first used by JAKUCS (1956, 1968, 1971). Although in the mountains studied there are no recent sites of bathycapture, over certain terrain (eg. on the Tés Plateau) present-day karst processes cna only be explained if previous bathycapture is assumed. - Investigation covered karst depressions, the already described types of covered karst landforms were regarded (QUINLAN 1972; JENNINGS 1975, 1985; BULL 1977; BÁRÁNY-JAKUCS 1984). - When studying paleokarstification and recent karstification, the data collected during various research were relied upon (SZABÓ 1956, 1968; BALÁZS 1984; FORD 1995).