Metamorphic history of the Algyő High (Tisza Mega-unit, basement of Great Hungarian Plain) A counterpart of crystalline units of the Koralpe-Wölz nappe system (Austroalpine, Eastern Alps).

Abstract

The Dorozsma Complex (DC) is defined and its main lithologies are described. The complex makes up the bulk of the Algyo basement high, representing an outlier of a Cretaceous nappe system in the southernmost part of the Tisza Mega-unit (Great Hungarian Plain). The DC exhibits a polymetamorphic history characterized by a Permian, low-pressure amphibolite facies metamorphism, overprinted by a pressure-dominated eo-Alpine, amphibolite facies metamorphism, accompanied by penetrative mylonitization. "Carboniferous breccias" described by earlier authors and covering the metamorphic rocks sporadically are redefined as tectonized, mostly cataclastic rocks. The uppermost unit of the basement below the Neogene sediments is a nappe composed of Triassic clastic and carbonate sediments. Petrographic similarities of the DC with several units of the Koralpe-Wolz nappe system in the Eastern Alps indicate that both units were formed within a continuous belt in the Cretaceous.