The Bükkalja Foothill area is a transitional hilly area between the tectonically uplifted Bükk Mountains and the subsiding Great Plain. Due to its transitional position and moderate tectonic uplift, younger geological strata are not denudated as it was in the central core of the Bükk mountains, which is a 20 km-by-7 km wide Mesozoic limestone plateau (called Giants’ Table) with a rim of white cliffs dominating the surrounding lower mountains and the maximum elevation at Mount Istállóskő (959 m). Because of the moderate uplift, the denudation of Bükkalja was not so intense as in the Bükk montains, therefore Mesozoic limestones are covered by younger sedimentary and volcanic strata. Various Eocene to Oligocene marine sediments, and Miocene rhyolite tuffs dominate at the surface, causing significant geodiversity and affecting the geomorphological conditions.

Lithology and topography Lithology and topography Egri-Bükkalja is a lithologically diverse area, since Miocene rhyolite tuffs prevail within the region, but the soil profiles of the catena at the Síkfőkút Forestry and Ecological Research Station are situated on the Upper Oligocene “Kiscelli clay”, and so called „Egri formation” which are also lithologically diverse formations of marine sediments, consisting of aleurit, clay, clayey marl, and locally also coarse sand and gravel rich in manganese lodes (Gyalog, 2005). Locally also redeposited volcanic tuffs (rhyolite tuff) occur, eroded from the surrounding areas. The average height of the surface is 320–340 m asl Higher plateaus are almost plain, dissected by NW-SE parallel valleys shaped by creeks coming from the higher regions of the Bükk mountains (Dobos, 2012).