Monitoring Ground Deformation at the Aquistore CO2 Storage Site with Radarsat-2 Radar

Abstract:

The research objectives of the Aquistore CO2 storage project are to design, adapt, and test non-seismic monitoring methods for measurement, and verification of CO2 storage, and to integrate data to determine subsurface fluid distributions, pressure changes and associated surface deformation. The test area is located west of the Boundary Dam Power Station in southeastern Saskatchewan,Canada. The targeted CO2 injection zones are within the Winnipeg and Deadwood formations located at > 3000 m depth. For measuring background (prior to CO2 injection) ground deformation at this site we employed the advanced satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) Multidimensional Small Baseline Subset (MSBAS) technique. DInSAR-MSBAS results were calculated based on over one hundred RADARSAT-2 images from five different ascending and descending beams acquired during 2012-2014. We detected slow ground deformation with a rate of up to 1 cm/year not related to CO2 injection but caused by different natural and anthropogenic causes (see attached figure - vertical deformation rate, range -+ 1 cm/year). We discuss in detail DInSAR-MSBAS processing chain and analyze precision of derived deformation rates and time series.