REVIEW OF NEOGENE AND QUATERNARY VOLCANISM OF THE CARPATHIAN PANNONIAN REGION

Development of the Pannonian Basins, as well as thrusting and folding of the Carpathians was accompanied by widespread volcanic activity. This volcanism can be divided into three main genetic types: (1) Early Miocene mainly acidic volcanism (tuffs and ignimbrites). The recent spatial separation of these volcanics may be due to large right lateral displacement along the Mid-Hungarian shear zone during the Early Miocene. (2) Middle Miocene-Pliocene calc-alkaline, mainly intermediate stratovolcanic complexes in the Inner Western Carpathians and in the East Carpathians, related to a subducted oceanic slab. Their geochemical compositions show a transitional character between active continental margin and island arc type magmatic rocks. The thickness of the crust increased with time and from west to east beneath this volcanic arc. (3) Pliocene-Pleistocene alkali basaltic volcanism was related to an upwelling, then cooling asthenospheric dome. This is thought to have initiated the thermal regime from which these Melts ascended. The compositional difference in space and in time might reflect the existence of local individual small-sized diapiric bodies as well as several processes (e.g. fractional crystallization, mixing), which modified the original magma. The eruption of these basaltic melts was temporally associated with the final phase of development of the Pannonian Basin. This volcanism was associated with recent uplifts and tectonic rejuvenation of the area.