Present crustal deformation pattern in the Pancardi Region: Constraints from Space Geodesy

It was almost a decade ago when the first space geodetic project was commenced in the Pannonian-Carpathian-Dinaric (PANCARDI) region with the aim of direct measurement of present crustal movements and strain. The most effective space geodetic technique for this purpose turned out to be the Global Positioning System (GPS). Several countries established their own national GPS network for monitoring crustal deformation. Nowadays stations of global, continental, regional, national and many local networks operate in the territory of the study area. An overview of these GPS geodynamic programs is given in the first section, then we analyse the data of the regional and the Hungarian national program and give short reports from other projects in the PANCARDI region. In our analysis we compare the velocities derived from space geodesy with those predicted by the NNR-NUVEL1A model based on geological and geophysical records. Looking into the intraplate crustal velocities the data show a fairly stable Bohemian Massive (BM) with relative crustal velocities smaller than 1 mm/yr. With reference to the BM in the north, the western part of the Alpine-North Pannonian (ANP) unit is moving to the East (E) with generally 1 mm/yr velocity that increases to more than twice this value towards its westernmost parts. The largest principal strain rate between these tectonic domains is a NE-SW oriented contraction (-8.62.510 - /yr (ppb/yr)) over an approximately 300300-km area. Here we observe left-lateral shear rate (97 7 ; 102 ppb/yr) between the Alpine-North Pannonian unit and the Bohemian Massif. South of the Alpine-North Pannonian unit the complex structure of junction of several tectonic domains can be described by northward trending velocities with 1-2 mm/yr north component relative to the ANP unit or the BM. The direction of contraction near the boundary of the Adriatic microplate is NW-SE oriented with magnitude of -8.05.3 ppb/yr over an area of 300120-km. Here we observe E-W oriented (93 13 ) right-lateral shear (125 ppb/yr) be-