Coseismic Deformation of the 2015 Mw 6.4 Pishan, China, Earthquake Estimated from Sentinel‐1A and ALOS2 Data

The 2015 M w 6.4 Pishan earthquake is the largest to have occurred in the Tarim basin since 1976. It caused great damage to infrastructures and private houses in the city of Pishan and the surrounding areas. We use ascending and descending interferometric Sentinel‐1A (S1A) and Advanced Land Observation Satellite 2 data to constrain the source parameters of this earthquake. The coseismic fault‐slip model obtained from a joint inversion indicates that the rupture is dominated by a thrust motion with a 7 km buried depth. The fault slip is centralized on a roughly 30 km (along‐strike) × 15 km (down‐dip) rectangular asperity, with ∼1  m maximum slip at a depth of 11 km. The total seismic moment 5.6×1018  N·m, corresponding to a moment magnitude M w 6.47, is slightly larger than the seismological estimate. The absence of fault slip in the upper 7 km of the crust suggests that this earthquake left an unruptured up‐dip fault under the city of Pishan. Both the coseismic fault‐slip distribution and the early postseismic deformation demonstrate that the S1A data have obvious superiority in monitoring earthquakes worldwide.

[1]  Masanobu Shimada,et al.  Line‐of‐sight displacement from ALOS‐2 interferometry: Mw 7.8 Gorkha Earthquake and Mw 7.3 aftershock , 2015 .

[2]  Xiaodian Jiang,et al.  Uplift of the West Kunlun Range, northern Tibetan Plateau, dominated by brittle thickening of the upper crust , 2013 .

[3]  Guangcai Feng,et al.  Geodetic model of the 2015 April 25 Mw 7.8 Gorkha Nepal Earthquake and Mw 7.3 aftershock estimated from InSAR and GPS data , 2015 .

[4]  F. Guangcai,et al.  Source parameters of the 2014 Mw 6.1 South Napa earthquake estimated from the Sentinel 1A, COSMO-SkyMed and GPS data , 2015 .

[5]  G. Feng,et al.  Shortcomings of InSAR for studying megathrust earthquakes: The case of the Mw9.0 Tohoku‐Oki earthquake , 2012 .

[6]  H. Zebker,et al.  Measuring two‐dimensional movements using a single InSAR pair , 2006 .

[7]  C. Werner,et al.  Sentinel-1 support in the GAMMA Software , 2015 .

[8]  S. Yoo,et al.  Joint inversion of seismic and geodetic data for the source of the 2010 March 4, Mw 6.3 Jia-Shian, SW Taiwan, earthquake , 2013 .

[9]  A. Ferretti,et al.  The Sentinel-1 mission for the improvement of the scientific understanding and the operational monitoring of the seismic cycle , 2012 .

[10]  John R. Elliott,et al.  The 2011 Mw 7.1 Van (Eastern Turkey) earthquake , 2013 .

[11]  Zhenhong Li,et al.  Retrieving three-dimensional displacement fields of mining areas from a single InSAR pair , 2014, Journal of Geodesy.

[12]  Urs Wegmüller,et al.  Gamma SAR processor and interferometry software , 1997 .

[13]  Xinjian Shan,et al.  Depth segmentation of the seismogenic continental crust: The 2008 and 2009 Qaidam earthquakes , 2011 .

[14]  Libo Han,et al.  Focal Mechanisms of the 2013 Mw 6.6 Lushan, China Earthquake and High‐Resolution Aftershock Relocations , 2014 .