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

KARSTIFICATION

^ ü~E\2 m? 0 5gm(ca.) Fig. 38. Hidden rock boundaries in cases of various assemblages of fault scarps and various thicknesses of cover sediments Legend: 1. carbonate rock; 2. loess; 3. hidden rock boundary stream erosion (Figs. 17, 47). Terrains of similar karstification are found in the SE of Mester-Hajag (Picts. 16,17; Figs. 19, 20), in the vicinity of the Augusztintanya and in karst terrains around Homód-árok (Fig. 21). In their interior karst depressions are arranged in rows or occur irregularly. In the area of pseudodepressions matter transport in depth is coupled with the related redeposition of cover sediments. The background to resulting karst features is the previous accumualtion terrains of depressions (with fossilising karst features) (Fig. 22). Karstification on a large block with cones On the surfaces of larger blocks a drainage network develops and exhumation takes place by the process of stream erosion. Valleys in such terrains, where karstification occurs on floors and side walls, are active or inactive well-developed or developing superimposed valleys. Exposure is either transversal or longitudinal (VERESS 1991). - In case of transversal exposure (Fig. 48) the directions of the cone row and of the valley are different. On the floor of the valley incised into the Csatka Gravel Formation karstic and non-karstic zones alternate. (In the latter sites the incision of the valley reached the summit level of the cone.) Karstification occurs where the valley floor reaches the carbonate rock. It takes place on valley floors covered by loess or redeposited cover sediments and covered karst ponor may be created on a hidden rock boundary (pseudobathycapture and blind valley development - eg. the covered karst ponor no K-l near the Kleintanya, Hárskút). Mostly, however, rows symmetric dolines-with-ponor formed on hidden rock boundary follow the floors of superimposed valleys (also including pseudoponors). During incision or the redeposition of the loess fill the cover sediment thins out over more and more cones and, thus, further dolines-with-ponor develop. The background areas of dolines-with-ponor are constituted by the floor of the superimposed valley and its side slopes. In pseudoponors or dolines-with-ponor deep fills accumulate since they function as traps for sediments removed from upstream valley floor sections. The exhumation of buried