Crustal structure in the Carpatho-Pannonian region: insights from three-dimensional gravity modelling and their geodynamic significance

Middle Miocene volcanism in the vicinity of the Middle Hungarian zone: Evidence for an inherited enriched mantle source

“…In their interpretation, even if southward-dipping subduction existed, it would have to be a relatively old feature overprinted by a younger most probably northward directed thrusting of the Alcapa unit. Furthermore, 2D and 3D gravitational modeling showed that a deep crustal root did not develop beneath the Western Carpathians which would be expected for a "classical" convergent margin (Szafián et al, 1997(Szafián et al, , 1999Szafián and Horváth, 2006). These later authors suggested alternatively that this is due to the fact that the Western Carpathians are characterized by transtensional-transpressional plate motions with little or no collision at least since the middle Miocene.…”

“…5;Kovács et al, 2007). The existence of well-developed subduction beneath the entire Western Carpathians is now also doubted by several geophysical studies as discussed above (i.e., Grad et al, 2006;Szafián and Horváth, 2006;Szafián et al, 1997Szafián et al, , 1999Wortel and Spakman, 2000). An alternative hypothesis has been proposed, where the lithospheric structure beneath the (the western portion of) Western Carpathians can be explained either by transcurrent motion of nappes along the orogen without major convergence of the subcrustal lithosphere (Szafián et al, 1997) or a collisional model implying a "crocodile mouth"-like structure .…”

“…This paradigm suggests that magmas were mainly produced by contemporaneous subduction-related arc volcanism along the Carpathians. Existence of a classic subduction margin for the entire Western Carpathians is now questioned by several authors (i.e., Grad et al, 2006;Szafián and Horváth, 2006;Szafián et al, 1997Szafián et al, , 1999Tomek, 1993). There is evidence to suggest the exsistence of subduction along eastern sections of the Western Carpathians-the roll-back effects of which can be used to account fro the observed block-rotations and fault patterns in the Northern Pannonian Basin (i.e., Bielik et al, 2004;Márton and Fodor, 2003;Sperner et al, 2002).…”

Crustal structure of the Pannonian Basin: The AlCaPa and Tisza Terrains and the Mid-Hungarian Zone

“…It has undergone multiple phases of tectonic activity through most of the Cenozoic, culminating in an episode of rapid lithospheric extension and contemporaneous shortening in the surrounding Carpathians during the mid-Miocene (~17.5-10.5 Ma), followed by late-Miocene to recent (~10.5-0 Ma) thermal subsidence and minor convergent reactivation (NE-SW) since ca. 5 Ma (Horváth et al, 1988;Csontos et al, 1992;Horváth, 1993;Tari et al, 1999;Horváth et al, 2006). Since the Pliocene there is clear evidence of minor NE-SW contraction which is attributed to the renewed convergence of Adria and Europe, as summarized by Cloetingh et al (2006).…”

“…In general, those models require convergence perpendicular to the present MHZ. They also assume that the observed deformation field is produced by a combination of boundary stresses due to a retreating Carpathian boundary (as described by Horváth, 1993) and extensional collapse of an over-thickened Alpine orogenic wedge (as discussed by Horváth et al, 2006). An indenting Adriatic plate created an initial condition of high topography in the Alps and Dinarides, after which internal buoyancy forces played the major role in producing synchronous extension in the basin and convergence in the Carpathians (Gemmer and Houseman, 2006).…”