Investigation of crustal motion in Europe by analysing the European VLBI sessions

Abstract

Since 1990 the International VLBI Service for Geodesy and Astrometry (IVS) has been performing geodetic Very Long Baseline Interferometry (VLBI) observations within the European geodetic VLBI network. In this work, 114 European VLBI sessions from January 1990 to September 2011 are analysed using the Vienna VLBI Software (VieVS). A total of 58 baselines with lengths ranging from 59 m to 4581 km are investigated and the lengths of most of them indicate repeatabilities at the sub-centimetre level. The horizontal station motions which describe the motion of the Eurasian plate are compared to the NUVEL-1A and MORVEL tectonic plate models. Intraplate crustal motions are investigated by estimating the station velocities with respect to Wettzell (Germany), a station on the geodynamically stable part of Eurasia. The northern part of Europe is dominated by the postglacial isostatic rebound, confirmed by four VLBI sites in this region with an uplift from 2.89±0.71 mm/yr (Svetloe, Russia) to 7.23±1.00 mm/yr (Ny-Alesund, Norway) with respect to the central part of the European plate. Besides the vertical uplift, these radio telescopes evidence a horizontal motion from the centre of the former ice sheet towards its border. In the southern part of Europe the motion of the VLBI sites is caused by the collision of the African plate with the Eurasian plate, while the stations on the stable part of Europe do not present any significant relative motions. Our results are compared against those by Haas et al. (J. Geodyn. 35:391–414, 2003) and with velocities of the current reference frame of the International Global Navigation Satellite Systems Service.