Tectonic and climatic forcing in Quaternary landscape evolution in the central Pannonian Basin: A quantitative geomorphological, geochronological and structural analysis

Relationship between Quaternary surface processes and crustal movements by quantitative measurement and comparison of landscape features in the Central Pannonian Basin are focussed. The Danube is the only river cutting through the Hungarian Mountain Range (HMR), offering a unique opportunity to determine its uplift rate via incision rates derived from terrace chronology. By a revision of existing terrace-chronological data along the Danube valley, incision rates were calculated for the last ~350 ka were ~0.2 mm/y at the flanks of the HMR and 0.4 mm/y in its axial zone, the Danube Bend. Terrestrial in situ produced cosmogenic 3He exposure age dating of strath surfaces in the Danube Bend provided an incision rate 4 times higher than the rate derived from earlier data sets, and suggests that the incision of the Danube started during the middle Pleistocene. The maximal incision rate of 1.6 mm/y was calculated by the 3He terrace ages for the last ~270 ka, considering the likely effect of some erosion of the strath surfaces after abandonment by the river. In the Gödöllo Hills, the NE part of the foothill-zone of the HMR, a thick Neogene sedimentary cover enabled to combine a DEM-based morphometric study with a structural analysis using seismic reflection profiles. Deflation created two ridges, considered as yardangs, where fluvial incision dissected the surface and overall lowering was smaller. These are separated by a wind channel where wind erosion caused severe surface denudation. Drainage anomalies developed as surface expressions of neotectonic deformation. Inverse reactivation of earlier normal faults and transpression along a former transtensional strike-slip zone caused structural warping of even the uppermost imaged horizons. Neotectonic inversion started in early Pliocene times (~4 Ma) and is characterised by a compressional stress-field with NE-SW maximal horizontal stress axis.Andriessen, P.A.M. [Promotor]Horvath, E. [Copromotor]Fodor, L. [Copromotor]Bada, G. [Copromotor

An outline of neotectonic structures and morphotectonics of the western and central Pannonian basin.

Neotectonic deformation in the western and central part of the Pannonian Basin was investigated by means of surface and subsurface structural analyses, and geomorphologic observations. The applied methodology includes the study of outcrops, industrial seismic profiles, digital elevation models, topographic maps, and borehole data. Observations suggest that most of the neotectonic structures in the Pannonian Basin are related to the inverse reactivation of earlier faults formed mainly during the Miocene syn- and post-rift phases. Typical structures are folds, blind reverse faults, and transpressional strike-slip faults, although normal or oblique-normal faults are also present. These structures significantly controlled the evolution of landforms and the drainage pattern by inducing surface upwarping and river deflections. Our analyses do not support the postulated tectonic origin of some landforms, particularly that of the radial valley system in the western Pannonian Basin. The most important neotectonic strike-slip faults are trending to east-northeast and have dextral to sinistral kinematics in the south-western and central-eastern part of the studied area, respectively. The suggested along-strike change of kinematics within the same shear zones is in agreement with the fan-shaped recent stress trajectories and with the present-day motion of crustal blocks derived from GPS data. © 2005 Elsevier B.V. All rights reserved