Improving the Resolving Power of InSAR for Earthquakes Using Time Series: A Case Study in Iran

Abstract

Interferometric Synthetic Aperture Radar (InSAR) is an established method to measure earthquake surface displacements. However, due to decorrelation and atmospheric noise, only a certain fraction of earthquakes is readily observable with single interferograms. To enhance the potential of retrieving InSAR earthquake observations, we apply InSAR time series analysis and use several recent earthquakes (Mw 5.6–6.3, 2018–2019) in Iran as case studies. We find that the coseismic displacement signals of these earthquakes, which might not be discernible within single interferograms, are better resolved using our approach. We reconstruct the coseismic deformation fields by fitting surface displacements using a time series approach. We find that the reconstructed coseismic deformation fields yield more robust and seismologically consistent earthquake modeling results when compared to single coseismic interferograms. Our work suggests that a time series approach is an effective way to improve the resolving power of InSAR for earthquake studies.