sentences:  Oldest rock form the crystalline core which is eccentrically situated at the southern periphery of the mountain range in two messifs denoted the Suchý and the Malá Magura massifs.Massifs are composed of migmatites, gneisses, amphibolites and granitoid rocks.Crystalline core is overlapped by the Triassic to Lower Cretaceous (Albian) deposits.