Crustal Motion Monitoring in Bulgaria and Surrounding Regions by Permanent GPS Array

GPS data from permanent sites in Bulgaria and the Balkans are used to monitor crustal motions and to constrain the regional geodynamics. Data from more than 70 permanent sites in Bulgaria and surrounding regions are processed and analyzed by GAMIT/GLOBK to obtain horizontal velocities. The results show overall motion in south Bulgaria and northern Greece to the south relative to Eurasia increasing from north to south. The horizontal velocities confirm the extensional regime in Southwest Bulgaria and Northern Greece outlying the presence of the South Balkan Extensional Region.