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

METHODS

valley can cut across the cavitation zone. During inheritance several other factors may prevent bathycapture on the ever longer limestone valley floors. According to JASKÓ (1961), in the Cuha stream there is no seepage from the channel to the influence of the Borzavár stream since the Cuha carries a load of high clay content from the Zirc Basin and lines its valley floor. The lining is impermeable. If incision did not reach the zone of flowing karst water, there are no subsequently exposed cavities in the valley side. It may occur that the floors of such valleys are subsequently lined by sediments. In this case, covered karst landforms can also develop on these valley floors. - A well-developed superimposed valley is active and receives abundant water from the covered terrains of the enclosing or neighbouring blocks in the early stage of inheritance (syngenetic valley). Particularly in the superimposed-antecedent (to a lesser extent in the superimposed-regressional) valleys intense incision exposes and destroys cavities in the flowing karst water zone. Rapid valley incision and, as it has been mentioned, because of the continuous exposure and destruction of caverns and passages no bathycapture could take place. A large part of the water, however, seeps away. The water lost by seepage further increases cavitation (see below) and the rate of valley incision. The different sections of valleys in the mountains vary according to the process of inheritance and thus in karstification. In the area of Hajag, for instance, the upper section of the Szilfakő Valley is a developed inactive superimposed valley, which exposes cavities in several sites. Along its lower section, in the central part of the Hárskút Plateau, however, the position of the enclosing block was lower and inheritance over limestone was of more moderate rate and the valley floor did not reach the zone of cavitation. Moreover, the valley was lined with unconsolidated cover sediments (mostly loess) or such sediments were preserved on the valley floor. Along the latter section of the valley the sites of recent karstification are associated with chimney formation.