Abstract. Geodynamic evolution of the Carpathian arc and Pannonian basin during the Neogene times is presented as a set of palinspastic reconstructions. The structural evolution is modeled in terms of a coupled system of: (1) Alpine (Atype) subduction and compressive orogene belt development owing to compression by the Adriatic microplate, (2) lateral extrusion of Alcapa lithosphere from the Alpine collision assisted by transform faults, (3) Carpathian gravity driven (Btype) subduction of oceanic or suboceanic lithosphere underlying former flysch basins and (4) back arc extension associated with the diapiric uprise of asthenospheric mantle.The variable timing of accretionary prism and back arc basin evolution in the Western Carpathians, the NW part of the Eastern Carpathians, and the SE part of the Eastern Carpathians confirms that the final Tertiary evolution of the Carpathian arc and Pannonian basin was not a uniform process. Rather, it took place successively in three segments, reflecting gravity driven subductions compensated by return asthenospheric flows (involving the back-arc diapiric uprise of asthenospheric mantle). The observed low subduction rate implies obstacles to the compensating asthenosphere flow, perhaps represented by confining thick lithosphere at the NW and SE sides of the arc. This segmentation may arise from a gravity driven process allowing asthenospheric side flow to take place speeding up the gravity driven overturn (subduction). Structural evolution as well as the timing and spatial distribution of the arc-type (subduction-related) andesite volcanics suggests that subduction halted because the subducting plate became nearly vertical, followed closely by the detachment of the sinking lithosphere slab from the continental margin. Late stage alkali basalt volcanic rocks imply that during the final stage of back arc basin evolution the related diapiric uprise of asthenospheric mantle incorporated unmetasomatized mantle material, brought possibly into the area of the diapiric uprise by compensating athenosheric mantle counterflows.Correspondence to: J. Lexa (lexa@gssr.sk)

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Abstract. Seismic activity in the Western Carpathians is closely related to the crustal rheology and combined structural pattern within the brittle upper crust. The structural pattern is a combination of three structural levels. The deepest level is represented by the Paleo-Alpine suture zones dissected by neo-Alpine fault structures, above all strikeslip fault zones (second level). The recent tectonic regimes are controlled by the contemporary stress field and vertical movements (third level). Following the analyses of structures and various geophysical data, the principal seismo-tectonic zones of the Western Carpathians are defined.The most remarkable and important first-order tectonic structure in the Western Carpathians is the zone of the Pieniny Klippen Belt, which represents the contact of the Western Carpathian internides and the stable European Platform.The Mur-Mürz-Leitha fault zone in the area of the Vienna Basin represents the contact of the Eastern Alps with the block of Western Carpathian internides. Both these tectonic lines represent subvertical boundaries with Tertiary tectonic activity.TheČertovica fault zone is a surface projection of the thrust plane of the Veporic thick-skinned sheet over the Tatric unit. Based on geological and geophysical data it is assumed that theČertovica zone is recently active due to its extensional reactivation. Earthquake events are released here mostly along the Hron fault system of the ENE-WSW direction.The next important tectonic structure is the HurbanovoDiósjenő line, which is most probably the continuation of the Rába line into the Slovak territory. Based on reflection seismic interpretations, there are several low-angle fault surfaces dipping to the SE. These thrust planes were reactivated durCorrespondence to: M. Kováč (kovacm@nic.fns.uniba.sk) ing the Miocene as low-angle extensional faults. The seismic events (e.g. Komárno area) are most probably generated on these low-angle surfaces.

Abstract:The position of the Gemeric Superunit within the Western Carpathians is unique due to the occurrence of the Lower Palaeozoic basement rocks together with the autochthonous Upper Palaeozoic cover. The Gemeric granites play one of the most important roles in the framework of the tectonic evolution of this mountain range. They can be observed in several small intrusions outcropping in the western and south-eastern parts of the Gemeric Superunit. Moreover, these granites are particularly interesting in terms of their mineralogy, petrology and ages. The comprehensive geological and geophysical research of the Gemeric granites can help us to better understand structures and tectonic evolution of the Western Carpathians. Therefore, a new and original 3D density model of the Gemeric granites was created by using the interactive geophysical program IGMAS. The results show clearly that the Gemeric granites represent the most significant upper crustal anomalous low-density body in the structure of the Gemeric Superunit. Their average thickness varies in the range of 5-8 km. The upper boundary of the Gemeric granites is much more rugged in comparison with the lower boundary. There are areas, where the granite body outcrops and/or is very close to the surface and places in which its upper boundary is deeper (on average 1 km in the north and 4-5 km in the south). While the depth of the lower boundary varies from 5-7 km in the north to 9-10 km in the south. The northern boundary of the Gemeric granites along the tectonic contact with the Rakovec and Klátov Groups (North Gemeric Units) was interpreted as very steep (almost vertical). The results of the 3D modelling show that the whole structure of the Gemeric Unit, not only the Gemeric granite itself, has an Alpine north-vergent nappe structure. Also, the model suggests that the Silicicum-Turnaicum and Meliaticum nappe units have been overthrusted onto the Golčatov Group.

The contribution contains of the geophysical data and their interpretation. Interpretation of geophysical fields in compliance with the geological structure and geodynamics EMO far region contributes significantly to development of seismotectonic model. The model represents the correlation between seismic activity and geological-tectonic setting. The achieved seismo-tectonic model in fact reasons all recorded seismic events in the area and points out to a seismic activity decrease towards the Danube Basin center, thereof, there being situated the EMO locality.