SENTINEL-1 PROCESSING AND ANALYSIS TO ESTIMATE GROUND DISPLACEMENT AND IDENTIFY ACTIVATION FAULTS, CASE STUDY OF THE 2017 Mw 7.3 EARTHQUAKE, NEAR THE IRAQ-IRAN BORDER

  • Ammar Abd Jasim Center of Remote Sensing, Ministry of Science and Technology, Baghdad, Iraq
  • Mustafa Ali Hassan Department of Geology, University of Baghdad, Baghdad, Iraq
Keywords: Earthquakes, Faults, Displacement, InSAR technique, Sentinel-1

Abstract

 Earthquakes are significant natural geohazards that threaten life and property. Iraq lies in a seismically active region, and most earthquakes result from the collision of the Eurasian-Arabian plates. On Nov. 12, 2017, an earthquake with 7.3 MW shook a large area of the Zagros Belt at the Iran-Iraq border. This work aims to use the InSAR technique for emphasis on the processing and analysis of Sentinel-1 data pre and post-earthquake supported by field, geological and tectonic information to map the ground deformation and fault activity caused by the Nov.12 earthquake. The case study involves a region located at the Iraq-Iran political boundaries. The results reveal that InSAR is a powerful tool to detect ground displacement and allow positioning faults. The interferogram results show that deformation extends to an area  ~ 6300 km2 and 7000 km2, with a maximum line-of-sight horizontal displacement ~87 cm and ~55 cm, vertical displacement ~121 cm uplifting and ~59 cm subsidence for ascending and descending data respectively, While pre-earthquake results show clearly neither displacement nor deformation took place. According to InSAR analysis, displacement direction, fault position detection, aftershock distribution, and the general geometric fault context, the blind back-thrust fault SW-dipping steeply occurred on the Zagros Front Fault was interpreted, in addition to new minor faults ruptured on the surface and displacement on old faults were detected. Many faults derived from the geological map coincide with the results of interferometric phase maps. Most recently discovered faults appear to be related to the Nov.12 earthquake.

Published
2020-04-29