Granite Weathering in the Velence Hills

Abstract

The landforms of granite weathering in the Velence Hills are unique in Central Europe. Through intensive weathering since the end of the Permian the exposed granite mass was transformed to saprolite. Weathering combined with sheet wash worked on the Eocene andesite too and resulted in heavy denudation. Since the Late Tertiary tectonic movements also contributed to the fragmentation of the granite mass, which was accompanied by the decay of the surface saprolite. The Velence Hills are best known for granite ridges and tors (balanced rocks). Tectonics had a fundamental contribution to the development of landforms. The water entering from both below and above to the joint network had a significant weathering effect on the one hand through its hydrothermal effect and on the other hand (from the other direction) through hydrolysis (both affected the feldspars and talcs of the granite). The landscape on surfaces decomposed hydrothermally or through hydrolysis are clearly distinguishable from the land form related to the intact granite surfaces.