Sentinel-1 TOPS Multitemporal Interferometry for Monitoring Slow Ground Motions Associated with Tectonic and Hydrological Processes
Abstract
Data from the Sentinel-1 synthetic aperture radar has already proven useful for investigating seismic and volcanic events, since its launch on April 2014. Yet, due to the requirement of ultrahigh coregistration accuracy and the relatively short time spanned by the Sentinel-1 acquisitions, its application for studying slow deformation processes, such as fault creep, land subsidence and uplift remains challenging. Additionally, the usefulness of Enhanced Spectral Diversity (ESD) algorithm to achieve the required coregistration accuracy and its effect on distorting the interferometric phase is debated. Here, we advance an existing multitemporal algorithm to analyze a set of 14 SAR images over the San Francisco Bay Area spanning 2015/03/01 to 2016/03/07. We first apply the Enhanced Spectral Diversity algorithm to achieve the required coregistration accuracy. We obtain good interferometric coherence and find that the coregistration error is weakly correlated with the interferometric baselines. In separate exercise, we apply a conventional coregistration approach and use precise orbits together with a reference digital elevation model. We find that the accuracy of coregistration using the conventional approach is comparable to that of ESD. We conclude that both approaches yield the required coregistration accuracy for making use of the phase measurements in time series analysis of ground deformation. Following a thorough validation test, we update our estimates of Hayward Fault creep rate, indicating the creep rate on the segment adjacent to the source of 1868 Mw 6.8 earthquake is slowed down. We further confirm the uplift due to recharge of the Santa Clara Valley aquifer system during the final summer of 4-year drought. Further details on the analysis and results are provided in Shirzaei et al. [2017]. Shirzaei, M., R. Bürgmann, and E. J. Fielding (2017), Applicability of Sentinel-1 Terrain Observation by Progressive Scans multitemporal interferometry for monitoring slow ground motions in the San Francisco Bay Area, Geophysical Research Letters, 44(6), 2733-2742.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFM.G34A..02S
- Keywords:
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- 1240 Satellite geodesy: results;
- GEODESY AND GRAVITY;
- 1241 Satellite geodesy: technical issues;
- GEODESY AND GRAVITY;
- 1294 Instruments and techniques;
- GEODESY AND GRAVITY;
- 1295 Integrations of techniques;
- GEODESY AND GRAVITY