Evolution of surface of planation: example of Transdanubian Mountains, Western Hungary

Abstract

This model claims that the surfaces of planation once produced by some erosional processes, were reshaped in the later geological periods by repeated, alternating erosional and accumulation processes on the morphostructure also repeatedly affected by tectonic uplift, subsidence end horizontal displacement. According to this model, late Mesozoic tropical etchplanation with paleokarst and bauxite formation did not continue during the Tertiary in the Transdanubian Mountains of Hungary. As a consequence of multiple differential tectonic subsidence, most of the range was buried in various thickness and at various intervals. This burial was followed by complete or partial exhumation on at least three occasions (Paleogene, Neogene and Quaternary). During repeated burial and exhumation the Cretaceous tropical etchplain was affected by further erosion or accumulation through non-tropical processes (such as peripedimentation, marine terrace formation, alluvial fan building and others), In the hoist series of die Transdanubian Mountains, divided by graben-like basins, the position and evolution of the geomorphological surfaces allows the identification of some main groups: 1. (semi) exhumed horst of etchplanation in summit position; 2. buried horst of etchplanation in uplifted position; 3. horst of etchplanation in threshold position, buried or exhumed and reshaped, mostly pedimented; 4. buried etchplain in basin position; 5. peripediments, rock pediments, locally buried under detritus. The model of geomorphic surface evolution through alternating erosion/accumulation does not only apply to the Hungarian medium-height mountains, but also to numerous other geomorphological regions, e.g. the Alpine-Carpathian-Dinaric Mountains, several old mountains and massifs of Europe and other continents.