A projekt kereteben Magyarorszag fiatal deformaciojat es felszinfejlődeset vizsgaltuk. Altalanos ervenyű megfigyelesunk szerint hazankban jelenleg is aktiv tektonikai folyamatok zajlanak, amelyek megertese es kvantitativ jellemzese nem csak tudomanyos feladat, hanem a tarsadalmi kihatasokat tekintve is kiemelkedő fontossagu. Geofizikai adatrendszerek egyuttes szerkezeti elemzese kimutatta, hogy a terseg jelenkori deformacioja alapvetően egykori toresvonalak ismetelt felujulasahoz kotődik. A szerkezetek bonyolult geometriaval rendelkező nyirasi ovekbe rendeződnek, jellemzően KEK-NyDNy-i csapassal. Az aljzat szerkezeti felepitesehez igazodo fiatal szerkezetek ismetelt (szeizmo)tektonikus felujulasa ismerhető fel. Geokronologiai vizsgalati eredmenyeink segitsegevel előrelepest tettunk a negyedidőszaki vertikalis keregmozgas es felszinfejlődes rekonstrualasaban. A Dunantulra meghatarozott kiemelkedesi es lepusztulasi ratak 0,1-2 mm/ev ertekek kozott valtoznak. Hasonlo sebessegűek az űrgeodeziai adatok alapjan becsult horizontalis keregmozgasok is. Aktiv tektonika es hidrografia kapcsolatanak vizsgalata alapjan kiderult, hogy a jelenkori differencialt fuggőleges keregmozgasok alapvetően befolyasoljak a vizfolyasok geometriai viszonyait. A medenceinverzio analog modellezesi eredmenyei azt mutatjak, hogy a Pannon-medence elsőrendű geomorfologiai habitusa kielegitően magyarazhato a litoszfera nagyleptekű gyűrődesevel. | The project aimed at the investigation of neotectonic deformation and surface evolution in Hungary. In general, it is recognised that the study area is characterised by active tectonic processes. The understanding and quantification of these processes represent a major scientific challenge and is of key importance considering their societal impact. The joint analysis of various geophysical datasets indicates that present-day deformation is mainly related to the reactivation of pre-existing faults. These faults are aligned in ENE-WSW oriented shear zones with rather complex internal geometry. These fracture systems are prone to repeated reactivation in the future, as also manifested in the morphotectonic habitat of the region. Geochronological studies assist the reconstruction of the Quaternary vertical deformation pattern and the main features of landscape development. Uplift and denudation rates for Transdanubia range between 0.1-2 mm/yr, whereas GPS measurements resulted in similar values for the rate of horizontal deformations. An intimate link between active tectonics and hydrography has been established suggesting that differential vertical surface movements have a major role in influencing the spatial arrangement and geometry of rivers. The results of analogue modelling show that the principle geomorphological character of the Pannonian basin can be adequately explained by large-scale folding of the lithosphere and related vertical deformation.
A projekt kereteben vegzett modszerfejlesztesek, illetve a kapott eredmenyek ertelmezesinek eredmenyei: a hazai archeomagneses adatbazis jelentős bővitese, uj teruletek finom felbontasu magneses terkepezese, szuszceptibilitas meresek alkalmazasa antropogen kornyezetszennyezes kimutatasara kulonboző kornyezeti komponensekben. A vizi es szarazfoldi geofizikai es egyeb modszerek integralt alkalmazasaval kialakitott modszertan eredmenyesen szolgalta a balatoni negyedidőszaki kornyezeti allapotok megismeresenek egy uj, magasabb fokat. Kimutattuk, hogy a meder alatt a to hossztengelyevel parhuzamos vetők vannak, amelyek a szarazfoldon is folytatodnak. A vetők szeles nyirt zonat alkotnak balos ertelmű elmozdulasokkal. A harantiranyu szerkezeti vonalak a Balaton medencejeben nem mutathatok ki, az ilyen iranyu morfologiai elemek kialakitasaban a szelerozio jatszott meghatarozo szerepet. Ezert a Balatont az oldaleltolodasos zona menten fellazult retegek deflacioval es abrazioval kialakitott depressziojakent ertelmezzuk. Tisztaztuk a pannoniai uledekekben megjelenő (valoszinűleg metan) gaz(ok) eloszlasanak kapcsolatat a pannonban kimutatott vetőzonakkal. Nevezetesen a to eszaki es kozepső reszen azonositott vetőzonak menten bizonyithato a gaz megjelenese, viszont a legdelebbi eltolodasos zonaban nem. A vizi szeizmika markans partvonal eltolodasokat tart fel, amely egyeb paleoklimatikai indikatorok es koradatok mellett lenyeges negyedidőszaki klimavaltozasokrol tanuskodik. | Main results of the project: Magnetometry: (i) Significant expansion of the archaeomagnetic database for Hungary, (ii) high resolution mapping of new areas both of geological and archaeological interest, and (iii) application of susceptibility measurements for various purposes including the detection of anthropogenic pollution in different environmental components. Integrated studies on Lake Balaton (using lacustrine and land seismic and other methods): (i) Verification of the presence of faults beneath the lake bottom and their continuation on land parallel to the long axis of the lake. The faults constitute a wide shear zone with sinistral displacements. Transversal structural trends are not apparent in the Balaton basin, consequently the occurrence of transversal trends in the morphology is not of tectonic origin. In the light of these findings, Lake Balaton is considered as a depression evolving by deflation and abrasion of the Pannonian strata broken up along the shear zones detected. (ii) Clarification of the link between the distribution of gases occurring in the Pannonian strata and the fault zones therein. Gas occurs along fault zones identified in the northern and middle part of the lake but does not occur along the southernmost zone. (iii) Verification, by lacustrine seismics, of pronounced shoreline displacements indicating - besides other palaeoclimatic and age information - significant climatic changes during the Quaternary.
We present the results of a fault reactivation study that used the analog modeling technique. The modeled tectonic processes represent the formation and subsequent deformation of the Derecske Trough and have implications for the evolution of the entire Pannonian basin system. Structural inversion of former thrusts led to normal faulting during the Miocene and corresponds to the formation, whereas subsequent reactivation of these faults in a strike-slip manner during the late Miocene to Quaternary represents neotectonic deformation of the basin. Modeling results show that reactivation of thrust faults in a transtensional manner can occur in a broad range of dip angles, and of angular differences between the maximum principal stress axis and the strike of the fault. The reactivation pattern of strike-slip zones in sandbox models critically depends on the orientation of the fault system with respect to the confining stress field, on the material property of the sand, and on the presence of a lubricant layer, representing a potential detachment horizon at the base of the models. The shear zones at the border zones of the Derecske pull-apart basin are prone to further reactivation, regarding the present-day stress field in the area. These inferences are confirmed by the recent seismic activity of the area, and point to the key importance of fault reactivation studies during seismic hazard assessment.
We present data and models for the present-day stress and strain pattern in the Pannonian Basin and surrounding East Alpine–Dinaric orogens. Formation of the Pannonian Basin within the Alpine mountain belt started in the early Miocene, whereas its compressional reactivation has been taking place since late Pliocene–Quaternary time. Basin inversion is related to changes in the stress field from a state of tension during basin formation in the Miocene to a state of compression resulting from the convergence between the Adria microplate and the European plate. Seismicity indicates that deformation is mainly concentrated along Adria's boundaries where pure contraction (thrusting...
