Monitoring Surface Deformation in Ecuador with InSAR: Insights into Tectonic, Volcanic, and Anthropogenic Processes

Geodetic measurements, encompassing GNSS and InSAR technologies, are pivotal in understanding Earth's surface deformation and evaluating natural hazards. This thesis focuses on the intricate tectonic, volcanic, and anthropogenic processes shaping Ecuador’s surface deformation, driven by the Nazca plate's subduction beneath the South American plate. Ecuador’s complex tectonic framework, including active fault systems and volcanic arcs, presents a unique challenge for deformation monitoring. The integration of GNSS and InSAR data provides a comprehensive approach to understanding these phenomena, addressing challenges posed by diverse land and vegetation cover, decorrelation, and regional geological intricacies.
Here, I use radar (SAR) data from the European Space Agency's (ESA) Sentinel-1 C-band satellite to generate a line-of-sight time series and measure displacements across Ecuador in both ascending and descending tracks. First, I analyzed deformation signals in Ecuador's inter-Andean valley between 2017 and 2023, identifying processes such as urban subsidence, resource extraction impacts, fault activity, and volcanic deformation. Major findings include geodetic slip and strain rate estimates for the Chingual-Cosanga-Pallatanga-Puna fault system, highlighting its active branches and potential hazards. Furthermore, my study reveals sustained uplift at Volcán Sangay during its recent eruption (2019–2022), attributed to magmatic volume increases beneath its western flank.

Finally, with advanced InSAR techniques and blind source separation methods, I analyzed a decade of satellite radar imagery to isolate deformation sources across 21 mainland Ecuadorian volcanoes. The results yield tailored monitoring strategies for individual volcanoes, capturing magmatic and non-magmatic signals. These findings underscore the potential of satellite radar data for country-wide volcanic monitoring and contribute valuable insights into Ecuador’s dynamic geophysical landscape, offering frameworks applicable to similar Andean settings and this research emphasizes the critical role of integrated satellite radar and GNSS analysis in advancing geohazard monitoring and resilience strategies.