New geodetic constraints on the role of faults and blocks versus distributed strain in the Nubia-Arabia-Eurasia zone of active plate interactions

Abstract

We present a broad view of present-day motions and deformations derived from uniform processing of GNSS observations within the Nubia-Arabia-Eurasia zone of plate interaction. The new observations we present provide a ~29% increase in the number of velocity determinations, a reduction in average station spacing from ~76 km to ~39 km, and an improvement in velocity uncertainties (for <1 mm/year), from 180 to 578 sites compared to our prior published solution (Reilinger et al., 2006). We use these new constraints to better evaluate the role of faults and blocks in controlling the character of continental deformation within the zone of plate interactions. Simple elastic block models show that internal deformation of the region occurs in large part on mapped, seismically active fault systems, indicating elastic behavior of the seismogenic crust (above ~15 km). For example, eastern central Anatolia, an area of > ~126,000 km2, bounded by the North and East Anatolian Faults exhibits internal velocity differences of <0.5 mm/year, indicating strain rates of