Coseismic surface deformation and fault model of the 27 May 2017 Mw 5.2 Saruhanlı-Manisa (western Turkey) earthquake from InSAR

Aylin Akoğlu

doi:10.3906/yer-1912-7

Abstract

The shortened revisit times and accurate orbits of the new generation of radar satellites like Sentinel-1 improved the applicability of the synthetic aperture radar interferometry (InSAR) technique to investigate more moderate size events. Here the technique is used to characterize the 27 May 2017 Mw 5.2 Saruhanlı (Manisa) earthquake that took place in western Turkey in the Gediz Graben. Though seismological focal mechanism solutions of the earthquake clearly indicated that the event is due to normal faulting, the nodal plane ambiguity and the presence of two closely located faults in the epicentral region prevented the assessment of the causative fault. Data from the Sentinel-1 radar satellites and subsequent modeling indicate that a 9-km-long, NE-dipping fault had ruptured during the earthquake with the shallow rupture coinciding with the Ozanca Fault in the region.

Highlights

Dominated by the interaction between the Arabian, Eurasian, and Nubian plates, Anatolia is one of the most seismically active continental regions of the world
While the North and East Anatolian fault zones that act as major boundaries between these plates are very well known and studied, the comparatively short and mostly blind networks of normal faults that produce frequent moderate events especially in western Anatolia and the seismic hazards associated with them are still poorly understood
In the last two decades, in addition to studies focusing on the major earthquakes of 1999 in İzmit-Düzce (Çakir et al, 2003; Konca et al, 2010) and 2011 in Van (Akoğlu et al, 2018 and references therein) and creep events along the North and East Anatolian faults (Cakir et al, 2005; Cavalié and Jónsson, 2014), InSAR has helped geoscientists study and document several previously unknown active faults of Anatolia and their corresponding parameters

Summary

Introduction

Dominated by the interaction between the Arabian, Eurasian, and Nubian plates, Anatolia is one of the most seismically active continental regions of the world. Shortened revisit times and accurate orbits that are possible with this new generation of satellites makes it possible to respond to earthquakes much faster than before, and increases the chance of studying these moderately sized events onshore in detail due to the overall increase in interferometric coherence (Funning and Garcia, 2019). In this manuscript an InSAR-based analysis of one of these moderately sized events shown, the 27 May 2017, Mw 5.2 Saruhanlı earthquake is presented making use of this rich Sentinel-1 archive.

24 Nov 08 Aug

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Discussion

Conclusions