Deep Deformation Pattern for the Carpathian-Pannonian Region

Abstract:

The Carpathian-Pannonian region (CPR) is the northeastern end of the Alpine mountain belt. In the Western Alps, available results of anisotropy investigations (SKS splitting) show clear belt-parallel anisotropy. In the Eastern Alps this pattern not only is broken but also does not follow the strike of Carpathians and Dinarides. In this study, we characterize upper mantle anisotropic structure and deep deformation pattern for the Carpathian-Pannonian region. We reprocess the SKS splitting parameters from the teleseismic events recorded by the Carpathian Basin Project (CBP) stations. We investigate these measurements together with the petrologic indicator of deformation in basalt-hosted upper mantle xenoliths from the Pannonian basin in terms of deformation geometry and its responsible tectonics. The observed anisotropy is referred to an asthenospheric origin and is interpreted as the flow/alignments within the upper mantle. We consider the models which have been suggested so far to explain the evolution and current stage tectonics of the Pannonian basin according to the deformation pattern observed from the SKS splitting results. This is followed by discussion about the (in)consistency between these models and our results. We present here the most plausible model of interaction between asthenospheric mantle with overlying and surrounding lithosphere which may possibly explain the deep deformation pattern in relation with the present-day tectonics of the CPR.