Geokinematics of Central Europe: New insights from the CERGOP-2/Environment Project

The Central European Geodynamics Project CERGOP/2, funded by the European Union from 2003to 2006 under the 5th Framework Programme, benefited from repeated measurements of thecoordinates of epoch and permanent GPS stations of the Central European GPS Reference Network(CEGRN), starting in 1994. Here we report on the results of the systematic processing of availabledata up to 2005. The analysis has yielded velocities for some 60 sites, covering a variety of CentralEuropean tectonic provinces, from the Adria indenter to the Tauern window, the Dinarides, thePannonian Basin, the Vrancea seismic zone and the Carpathian Mountains. The estimated velocitiesdefine kinematical patterns which outline, with varying spatial resolution depending on the stationdensity and history, the present day surface kinematics in Central Europe. Horizontal velocities areanalyzed after removal from the ITRF2000 estimated velocities of a rigid rotation accounting forthe mean motion of Europe: a ~2.3 mm/yr north-south oriented convergence rate between Adria andthe Southern Alps that can be considered to be the present day velocity of the Adria indenterrelative to the European foreland. An eastward extrusion zone initiates at the Tauern Window. Thelateral eastward flow towards the Pannonian Basin exhibits a gentle gradient from 1-1.5 mm/yrimmediately east of the Tauern Window to zero in the Pannonian Basin. This kinematic continuityimplies that the Pannonian plate fragment recently suggested by seismic data does not require aspecific Eulerian pole. On the southeastern boundary of the Adria microplate, we report a velocitydrop from 4-4.5 mm/yr motion near Matera to ~1 mm/yr north of the Dinarides, in the southwesternpart of the Pannonian Basin. A positive velocity gradient as one moves south from West Ukraineacross Rumania and Bulgaria is estimated to be 2 mm/yr on a scale of 600-800 km, as if the crustwere dragged by the counterclockwise rotation along the North Anatolian Fault Zone. This regimeapparently does not interfere with the Vrancea seismic zone: earthquakes there are sufficiently deep(> 100 km) that the brittle deformation at depth can be considered as decoupled from the creep atthe surface. We conclude that models of the Quaternary tectonics of Central and Eastern Europeshould not neglect the long wavelength, nearly aseismic deformation affecting the upper crust in theRomanian and Bulgarian regions

Short-term and long-term variability of antenna position due to thermal bending of pillar monument at permanent GNSS station

The variability of daily site coordinates at permanent GNSS station is a sum of many disturbing factors influencing the actual satellite observations, data processing, and bias modelling. In the paper are analysed possibilities of monitoring the instability of GNSS antenna pillar monument by the independent observations using the precise inclination sensor. Long-term series from three different types of pillars show specific features in amplitude and temporal evolution of monument bending. Correlations with daily temperature and/or solar radiation changes were proved

Refinement of the velocity field in Central Europe based on reprocessed permanent and epoch-wise GPS observations

The history of regular GPS monitoring aimed to investigation of geokinematics in Central Europe started in early ninetieth of the 20th century. In 1994 the first campaign of epoch-wise Central Europe Geodynamics Project (CERGOP) was organized and serval pernament GPS stations in region became operational; relevant data from about 30 sites are available for that period. Since that time the number of permanent and epoch stations with accessible suitable for geokinematical research increased to about 150. Although the GPS observations were continuously analyzed and also several re-analyses were performed, the complex combination of all data still suffer fromb inhomogeneities of various kind, e.g. no unique GPS antenne models, effects of reference fram evolution, troposphere models improvements, identyfication and modeling of discontinuities in observing series, etc. In this paper is introduced a new complex solutions for 3-dimensional site velocities which is based on GPS permanent and epoch data reprocessed by unified procedures and models related to homogeneous reference frame. The subsequent horizontal velocity field analyses are focused on modelling of regional geokinematical trends and identification of local anomalies where the significant disagreement of the actual site velocity with the regional pattern is observed

Analysis of CEGRN 2005 as the eighth of CERGOP observing campaigns

Strategy of analysis and results from solution of CEGRN epoch campaign in 2005 Combined solution of CEGRN 2005 based or individual solutions from six an: centres and its comparison with CEGRN 2003 coordinates. Time evolution of coordinates at some long-term observed CEGRN sites obtained during epoch camp since 1994 and the related problems

Geokinematics of Central Europe: new insights from CERGOP-2/Environment Project

The CERGOP2 project funded by the European Union from 2003 to 2006 under the 5th Framework Programme benefits from repeated measurements of the coordinates of epoch and permanent GPS stations forming the CEGRN network in Central Europe, starting 1994. We report on the results of the systematic processing of the available data up to 2005. The analysis work has yielded the velocities of some 60 sites, covering a variety of Central European tectonic provinces, from the Adria indenter to the Tauern window, the Pannonian basin, the Vrancea Seismic Zone and the Carpathian Mountains. The estimated velocities define kinematical patterns which outline, with varying spatial resolution depending on the station density and history, the present day tectonic flow in Central Europe.The CEGRN data show that the majority of active contraction originating from the Eurasia Nubia plate boundary and the microplate between them is taken up primarily in the Eastern Alps, the Dinarides, and the Pannonian Basin. After removal from the ITRF2000 velocities of a rigid rotation accounting for the mean motion of stable Europe, the residual velocities have random orientations with 0.3 mm/yr scatter. This Iow figure provides an upper estimate for the level of rigidity of the European Platform. A 2.3 mm/yr north-south oriented convergence rate is implied by our data between Adria and the Southern Alps, and a narrow - -60 km wide- contraction zone in the Southern Alps is identified, consistently with earlier results. An eastward extrusion north of the contraction zone corresponds with the extension of the Tauern Window. In the southeastern boundary of the microplate, 4-4.5 mm/yr motion of Adria decreases to -1 mm/yr through the microplate, its boundary, and the Dinarides mountain range towards the southwestern part of the Pannonian Basin. Our data suggest that if the Pannonian Basin is subject to deformation, then it is most likely to be compressional than extensional. We conclude that compression and associated contraction due to the Adria collision with the Alps and the Dinarides is likely to fade away in the Western and Northern Carpathians, where our velocities and strain rates show no significant deformation

Analysis of CEGRN 2005 as the eighth of CERGOP observing campaigns

Strategy of analysis and results from solution of CEGRN epoch campaign in 2005 Combined solution of CEGRN 2005 based or individual solutions from six an: centres and its comparison with CEGRN 2003 coordinates. Time evolution of coordinates at some long-term observed CEGRN sites obtained during epoch camp since 1994 and the related problems