Interseismic strain accumulation across the North Anatolian Fault from Envisat InSAR measurements

[1] The North Anatolian Fault (NAF) is a major feature of Middle Eastern tectonics, and several previous InSAR studies have measured interseismic deformation across the fault. All previous studies, however, have used SAR data acquired from a single line-of-sight (LOS) direction, leading to large uncertainties on model parameters and necessitating several modelling assumptions to be made. We have measured interseismic deformation across the NAF using both ascending and descending SAR data for the first time, an aim that has previously been limited by the availability of ascending data. By using SAR data from two look directions we have been able to reduce the range of uncertainties in slip rate and locking depth from previous studies by 60%, and by assuming no vertical motion across the fault, we estimate both fault-normal and fault-parallel motion. These results support other evidence for predominantly horizontal strike-slip motion on the NAF. Our data are consistent with a slip rate of 20–26 mm/yr below a locking depth of 13.5–25 km for the NAF.

[1]  P. Rosen,et al.  Updated repeat orbit interferometry package released , 2004 .

[2]  T. Wright,et al.  Measurement of interseismic strain accumulation across the North Anatolian Fault by satellite radar interferometry , 2001 .

[3]  R. Armijo,et al.  Long-term evolution of the North Anatolian Fault: new constraints from its eastern termination , 2009 .

[4]  C. Werner,et al.  Radar interferogram filtering for geophysical applications , 1998 .

[5]  R. Finkel,et al.  A late Holocene slip rate for the central North Anatolian fault, at Tahtaköprü, Turkey, from cosmogenic 10Be geochronology: Implications for fault loading and strain release rates , 2009 .

[6]  J. C. Savage,et al.  Geodetic determination of relative plate motion in central California , 1973 .

[7]  T. Wright,et al.  Multi-interferogram method for measuring interseismic deformation: Denali Fault, Alaska , 2007 .

[8]  Mahdi Motagh,et al.  Strain accumulation across the Gazikoy–Saros segment of the North Anatolian Fault inferred from Persistent Scatterer Interferometry and GPS measurements , 2007 .

[9]  D. McKenzie.  Active Tectonics of the Mediterranean Region , 1972 .

[10]  David A. Seal,et al.  The Shuttle Radar Topography Mission , 2007 .

[11]  R. Armijo,et al.  Morphology, displacement, and slip rates along the North Anatolian Fault, Turkey , 2002 .

[12]  S. Ergintav,et al.  Kinematics of the eastern part of the North Anatolian Fault Zone , 2010 .

[13]  Demitris Paradissis,et al.  GPS constraints on continental deformation in the Africa‐Arabia‐Eurasia continental collision zone and implications for the dynamics of plate interactions , 2005 .

[14]  A. Barka,et al.  Slip distribution along the North Anatolian fault associated with the large earthquakes of the period 1939 to 1967 , 1996, Bulletin of the Seismological Society of America.