Measurement results indicate that the slip rate of the NAFZ increases westwards within about 400 km from 16.3 卤 2.3 mm/year to 24.0 卤 2.9 mm/year, in consistence with the observation that the Anatolian block is being pulled by the Hellenic trench rather than being pushed by the Arabian plate as a result of continental collision between the Arabian and Eurasian plates in eastern Turkey since late Miocene. Modelling the GPS velocities shows that fault locking depth increases also in the same direction from 8.1 卤 3.3 km to 12.8 卤 3.9 km. Slip rate decreases as moving off the Hellenic trench. An average slip rate of 20.1 卤 2.4 mm/year and a locking depth of 12.5 卤 3.5 km are also estimated for the entire study area by using all of the GPS measurements obtained in this study. The GPS velocities are in good agreement with the kinematic models created by paleomagnetic studies in the region and complete the overall picture.