1. Synthetic aperture radar (SAR) data … also, use ENVISAT (C-band) data from the same time period to resolve vertical/horizontal components of surface velocity (C-band data suffer from decorrelation in the study area) ALOS satellite of JAXA (Japan Aerospace Exploration Agency) distance between repeated orbits 5 ALOS ascending tracks 10-30 radar interferograms in each track Time span: 2007-2010 Radar wavelength: 23.6 cm (L-band)

2. Shallow fault creep inferred from InSAR Creep rate of up to ~10 mm/yr (~40% of relative plate motion) Lateral extent: ~75 km Consistent with Cakir et al. (2005): C-band ERS data 9 years (from 1992 to 2000) and ENVISAT data (2003-2010, this study)

3. Conclusions The LOS velocities reveal discontinuities of up to ~6 mm/year across the Ismetpasa segment of the NAF, implying surface creep at a rate up to ~10 mm/yr; this is a large fraction of the inferred fault slip rate (20-25 mm/yr) The lateral extent of significant surface creep is about 75 km, broadly consistent with results of previous studies Neighboring fault sections do not exhibit shallow creep within the measurement accuracy (1-2 mm/yr) The inferred depth extent of “shallow” fault creep at Ismetpasa is 6-7 km, suggesting that the deeper locked portion of the partially creeping segment is characterized by a higher stressing rate (smaller events? shorter recurrence interval?) Dynamic models that incorporate rate-and-state friction combined with geodetic observations of interseismic deformation due to mature active faults can be used to infer in situ rate-state parameters of seismogenic crust