The Pannonian region is a back-arc basin located within the arcuate Alpine–Carpathian mountain chain in central Europe. Beneath the basin both the crust and the lithosphere have smaller thickness than the continental average. During the last few decades several studies have been born to explain the formation of the Pannonian Basin but several key questions remain unanswered. In this study we construct a new high-resolution 3D P-wave velocity model of the crust and uppermost mantle in the Pannonian Basin which may help us to understand better the structure and evolution of the region. For the 3D P-wave velocity structure estimation over 32 thousand traveltime picks have been derived from the ISC bulletin and the local Hungarian National Seismological Bulletin, and altogether we used more than 3200 seismic events (local, near-regional and regional) and more than 150 seismic stations from the time period between 2004 and 2014. For the 3D velocity field inversion we used the FMTOMO software package which uses the so called Fast Marching Method for calculating the traveltime estimations, and the subspace inversion method to recover the model parameters. We also performed several checkerboard tests both to select the appropriate regularization parameters and to help the interpretation of the resulting P-wave velocity model. On the resulting tomographic image the seismic velocity anomalies well resolve the effects of deep sedimentary basins and also Moho topography and the associated updomings of the asthenosphere below the Pannonian Basin. Different major tetonic units and fault zones separating those seem to show characteristic velocity anomalies. Subrecent volcanic activity or associated melt and fluid percolation, heat transfer in the upper mantle and crust may also have an impact on the propagation of seismic waves.
ASJC Scopus subject areas
- Building and Construction