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

KARSTIFICATION

- Where do sites of valley development occur related to the paleokarst features. - What kind of karstic rocks occur on the enclosing block and in what distribution? - The altitude and relative evolution and extension of the enclosing block. - The rate and nature of Quaternary uplift (cyclic or gradual), the way of uplift (uniform or tilted). - The date of the beginning and the end of valley superimposition (when did they occur related to block uplift, loess formation and karst water accumulation). - The position of flowing karst water related to the carbonate basement during the formation of karst water level. How uniform and deep is the cavity system of the zone of flowing karst water. An overview of the types of karstification outlined below is provided in Table TV. and Fig. 37. Types of karstification independent of flowing karst water The karstification independent of flowing karst water takes place blocks or on groups of blocks which had been uplifted by the time the zone of flowing karst water (main karst water or karst water storeys). By the time of cavernation, in such blocks the karst water table was in a deeper position related to the surface of the carbonate basement or no valleys developed the floors of which could incise down to the karst water table. It may have occurred that the still developing superimposed valleys reached and exposed cavities above the karst water table. Subsequently, however, their development came to a halt since the denudation of cover sediments from their environs left them without a water-course (inactive well-developed superimposed valley). On such blocks no valley evolution by cavity exposure could or can happen. In the sides of inactive well-developed superimposed valleys cavities of smaller size (some tens of centimeters diameter) can occur. These features are remnants of the zone of cavernation of moderate vertical extension formed before the inheritance of the valley. The karstification here is affected by rainwater infiltrated into the permeable cover (loess). Karst water or the cavities formed by karst water exert no influence on karstification. The denudation (or accumulation) of cover sediments may take place in carbonate terrain dissected by fault scarps, elevations (cones) and paleokarst depressions. Cover sediments may be eroded (thinned out) by sheet wash, stream erosion and matter transport in depth. The different types of karstification produce different densities, distributions, sizes, types, positions and geomorphological environs of karst features (or relative frequencies of various karst feature types). In addition to the above factors, the character of exhumation and thus the type of karstification also depends on the dimensions of blocks or groups of blocks, their altitudes and relative heights and the preceeding geomorphic history. Thus subtypes and varieties can be indentified. As a consequence of numerous factors and of a limited number of karstic terrain, karstification on the individual blocks or groups of blocks is of individual nature. Karstic microregions, however, could not form in the mountains since karst features are of small size and low density and karstification is unable to determine the face of blocks or groups of blocks. The following types of exhumation are distinguished (Table IV). Karstification in terrain with covered fault scarps In carbonate terrains dismembered by fault scarps, hidden rock boundary can develop on the edges of fault scarps, particularly, if scarps are also tilted (Fig. 38). Dolines-with-