Large-scale Miocene igneous activity in the Carpathian-Pannonian Region, Central Europe—Magma generation and differentiation processes at the NE part—
Japanese Magazine of Mineralogical and Petrological Sciences
Large-scale Miocene igneous activity in the Carpathian Pannonian Region, Central Europe -Magma generation and diŠerentiation processes at the NE part- クラッシャイ・ジタ(Zita KRASSAY) Large-scale igneous activity characterised the development of the Carpathian Pannonian Region, Central Europe from Late Cretaceous to Pleistocene times, with a peak of activity during the Miocene. The magmatism is considered to have been caused by the closure of the Tethys Sea and consequent collision between the
... between the African and Eurasian plates, but the exact mechanism for magmageneration is still a matter of debate. In order to get a better understanding of magmageneration and diŠerentiation processes, a new set of bulk chemical data, including trace and rare earth elements has been presented on igneous rocks from the NE part. Together with published data, igneous rocks from the three regions of the research area (Tokaj Slanske Mts., Great Plain and Transcarpathia) cover a wide spectrum of the calc alkaline series and reveal close similarities in both petrography and geochemistry. No sig-niˆcant spatial diŠerences could be revealed in terms of major element chemistry but Nb and Zr trends slightly diŠer in Tokaj Slanske Mts. Great Plain and Transcarpathia. Felsic rocks formed mainly at the earlier stages, the most maˆc sample at the latest stage of the igneous activity. Alkali basaltic activity (generally characterising the development of the Carpathian Pannonian Region from 11.7 Ma) has not been observed at the NE part. The results of crystallization and mixing calculations on igneous rocks from the area of research show that geochemical characteristics of most rocks cannot be explicitly explained by crystallization processes alone and they re‰ect the involvement of various (upper crustal, lower crustal, upper mantle and alkali basaltic) source materials through magma mixing, assimilation and contamination. The diŠerent spatial Nb and Zr trends may be interpreted as the outcome of mainly crustal contamination in the case of rocks from Transcarpathia, as opposed to the joint eŠects of upper crustal contamination and the involvement of alkali basaltic magma in the case of rocks from the Tokaj Slanske Mts. Thus, alkali basaltic magma may have been involved in the formation of calc alkaline igneous rocks not only as heat source, but in the case of basaltic rocks, also as material.