Investigating ground deformation due to a series of collapse earthquakes by means of the PS-InSAR technique and Sentinel 1 data in Kandy, Sri Lanka

A series of collapse earthquakes in Kandy, Sri Lanka, has been linked to significant ground deformation, with uplift rates reaching +20 mm/year over urban areas and subsidence of up to -40 mm/year near Victoria Dam. This finding emerges from a study employing PS-InSAR (Permanent Scatterer Interferometry) and D-InSAR (Differential InSAR) techniques using Sentinel 1A satellite data from 2019 to 2021. The research also identified subsidence along the Mahaweli river lineament, ranging from -29 to -36 mm/year, and correlated deformation areas with landslide risk. Additionally, irregularities in terrestrial and groundwater levels were detected using GRACE-Follow-On data, suggesting dynamic geological activity. This study serves as a prototype for investigating low-magnitude incomplete collapse earthquakes in diverse geotechnical settings.

Welikanna, D. R., & Jin, S. (2023). Investigating ground deformation due to a series of collapse earthquakes by means of the PS-InSAR technique and Sentinel 1 data in Kandy, Sri Lanka. Journal of Applied Remote Sensing, 17(01), 1–27. https://doi.org/10.1117/1.jrs.17.014507