Comprehensive InSAR analysis using ARIA standard products captures earthquake cycle processes across California

Simran S. Sangha, David P. Bekaert, & Gareth J. Funning

Published August 11, 2020, SCEC Contribution #10381, 2020 SCEC Annual Meeting Poster #169

Interferometric Synthetic Aperture Radar (InSAR) is an established technique for mapping displacements of the Earth's surface. The Advanced Rapid Imaging and Analysis (ARIA) Center for Natural Hazards project provides open and free access to an operational archive of standard Sentinel-1 Geocoded UNWrapped interferogram (GUNW) products. The existing archive of ARIA products provides complete coverage across all of California spanning from late 2014 through to the present day across 9 ascending and descending geometry tracks.

We leverage this archive to generate higher level line-of-sight time-series analyses and capture the signatures of earthquake cycle deformation and non tectonic processes across the state of California. To accomplish this, we use the open source-packages ARIA-tools and MintPy to pre-process and compute time-series analyses using the Small Baseline Subset method, respectively. To mitigate low coherence gaps in the time-series, we supplement the analysis with annual pairs spanning high coherence periods (e.g. summer to summer); allowing us to retrieve the complete time-series history across the Sentinel-1 record. In our analysis, we assess the impact of tropospheric noise corrections derived from the ECWMF operational weather model through the GACOS service on our estimated long-term deformation rates and their uncertainties. We validate our results against deformation rate estimates from regional GNSS networks over the same duration.

We plan to contribute our results to the processing methodology comparisons currently being undertaken by the Community Geodetic Model InSAR working group. We will also use the rates to invert for interseismic fault slip and shallow fault creep rates.

Citation
Sangha, S. S., Bekaert, D. P., & Funning, G. J. (2020, 08). Comprehensive InSAR analysis using ARIA standard products captures earthquake cycle processes across California. Poster Presentation at 2020 SCEC Annual Meeting.

Related Projects & Working Groups
SCEC Community Models (CXM)